JP2018121394A - Rotating machine control device and rotating machine control method - Google Patents

Abstract

A control device capable of switching between a control mode capable of suppressing a decrease in control performance when the rotational speed of a three-phase rotating machine is low and a control mode capable of ensuring high responsiveness to torque when the rotational speed is high. And the control apparatus suitable for suppressing the torque fluctuation at the time of control mode switching is provided. A movement amount specifying unit 111 calculates a product of a command speed of a three-phase rotating machine 102 and a cycle of a control cycle, and in a first control mode, a vibration component of an estimated torque approaches zero. In the control mode, the first movement amount, which makes the difference between the command torque and the estimated torque close to zero, is specified, and the phase of the primary magnetic flux vector moves in one control cycle by summing the product and the first movement amount. The second movement amount to be performed is specified. [Selection] Figure 4

Description

  The present disclosure relates to a rotating machine control device and a rotating machine control method.

  Conventionally, direct torque control (DTC) has been proposed (see, for example, Patent Document 1). Patent Document 2 proposes a technique for suppressing a reduction in control performance that becomes apparent when the rotational speed of a three-phase rotating machine is low.

Japanese Patent No. 3485844 JP 2006-100994 A

  A control device capable of switching between a control mode capable of suppressing a decrease in control performance when the rotational speed of the three-phase rotating machine is low and a control mode capable of ensuring high responsiveness to torque when the rotational speed is high. A control device suitable for suppressing torque fluctuation during control mode switching has not been proposed. Therefore, the present inventors aimed to produce such a control device.

That is, this disclosure
A rotating machine control device that applies a voltage vector to the three-phase rotating machine using an inverter so that a primary magnetic flux vector of the three-phase rotating machine follows the command magnetic flux vector,
The rotating machine control device can switch between a second control mode for causing the torque of the three-phase rotating machine to follow a command torque, and a first control mode different from the second control mode,
The rotating machine control device includes:
A torque estimator that estimates the torque of the three-phase rotating machine using the primary magnetic flux vector and the current vector of the three-phase rotating machine;
A phase estimator for estimating the phase of the primary magnetic flux vector;
The product of the command speed of the three-phase rotating machine and the cycle of the control cycle is calculated, and the estimated vibration component of the torque is approximated to zero in the first control mode, and the command in the second control mode. By identifying a first movement amount that approximates the difference between the torque and the estimated torque to zero, and summing the product and the first movement amount, the phase of the primary magnetic flux vector is determined in one control cycle. A movement amount specifying unit for specifying the second movement amount to be moved;
A command phase specifying unit that specifies a command phase that is a phase of the command magnetic flux vector using the estimated phase and the second movement amount;
There is provided a rotating machine control device comprising: a command magnetic flux specifying unit that specifies the command magnetic flux vector using the command phase.

  The rotating machine control device according to the present disclosure includes a control mode capable of suppressing a decrease in control performance when the rotational speed of the three-phase rotating machine is low, and a control mode capable of ensuring high response to torque when the rotational speed is high. And can be switched. In addition, this rotating machine control device can suppress torque fluctuations during control mode switching.

Block diagram of three-phase rotating machine, inverter and rotating machine control device Diagram for explaining the dq coordinate system Diagram for explaining αβ coordinate system The block diagram of the rotary machine control part which concerns on Embodiment 1. FIG. The block diagram of the movement amount specific | specification part which concerns on Embodiment 1. FIG. The figure for demonstrating the switching method of the control mode in Embodiment 1. FIG. Configuration diagram of PWM inverter Block diagram of rotating machine control unit according to embodiment 2 The block diagram of the movement amount specific | specification part which concerns on Embodiment 2. FIG. Block diagram of a rotating machine control unit according to Embodiment 3 The block diagram of the movement amount specific | specification part which concerns on Embodiment 3. FIG. Diagram for explaining magnetic flux vector and current vector Diagram for explaining examples of calculation formulas for obtaining command amplitude Block diagram of amplitude correction amount generator

(Knowledge by the present inventors)
In an example of direct torque control, the rotational speed of the three-phase rotating machine is estimated based on the voltage vector of the three-phase rotating machine. The speed controller generates reference torque for the three-phase rotating machine based on the rotation speed. Then, using the reference torque as the command torque, the three-phase rotating machine is controlled so that the torque of the three-phase rotating machine follows the command torque. According to the study by the present inventors, in this way, when the rotational speed is high, high responsiveness to torque can be ensured. However, when the rotation speed is low, the control tends to become unstable. This is because in this case, an error (voltage error) between the voltage vector used as information in the control and the voltage vector actually applied to the three-phase rotating machine tends to be large, and the rotational speed estimation accuracy is ensured. This is because it is difficult to pulsate the reference torque.

  Patent Document 2 proposes a technique for suppressing a decrease in control performance when the rotational speed of a three-phase rotating machine is low. However, according to the study by the present inventors, this technique is not necessarily suitable for ensuring high response to torque when the rotational speed of the three-phase rotating machine is high.

  When different control modes are used depending on whether the rotational speed is low or high, the voltage of the three-phase rotating machine may suddenly vary when the control mode is switched, and the torque may vary greatly. As far as the present inventors know, no technology suitable for suppressing this variation has been proposed.

  Therefore, the present inventors have a control mode capable of suppressing a decrease in control performance when the rotational speed of the three-phase rotating machine is low, and a control mode capable of ensuring high responsiveness to torque when the rotational speed is high. The present invention aims to produce a control device that can be switched, and that can suppress torque fluctuations during control mode switching.

The first aspect of the present disclosure is:
A rotating machine control device that applies a voltage vector to the three-phase rotating machine using an inverter so that a primary magnetic flux vector of the three-phase rotating machine follows the command magnetic flux vector,
The rotating machine control device can switch between a second control mode for causing the torque of the three-phase rotating machine to follow a command torque, and a first control mode different from the second control mode,
The rotating machine control device includes:
A torque estimator that estimates the torque of the three-phase rotating machine using the primary magnetic flux vector and the current vector of the three-phase rotating machine;
A phase estimator for estimating the phase of the primary magnetic flux vector;
The product of the command speed of the three-phase rotating machine and the cycle of the control cycle is calculated, and the estimated vibration component of the torque is approximated to zero in the first control mode, and the command in the second control mode. By identifying a first movement amount that approximates the difference between the torque and the estimated torque to zero, and summing the product and the first movement amount, the phase of the primary magnetic flux vector is determined in one control cycle. A movement amount specifying unit for specifying the second movement amount to be moved;
A command phase specifying unit that specifies a command phase that is a phase of the command magnetic flux vector using the estimated phase and the second movement amount;
There is provided a rotating machine control device comprising: a command magnetic flux specifying unit that specifies the command magnetic flux vector using the command phase.

  The rotating machine control device according to the first aspect includes a control mode (first control mode) capable of suppressing a decrease in control performance when the rotation speed of the three-phase rotating machine is low, and a high response to torque when the rotation speed is high. It is possible to switch between a control mode (second control mode) that can ensure safety. In addition, this rotating machine control device can suppress torque fluctuations during control mode switching.

The second aspect of the present disclosure includes, in addition to the first aspect,
In the first control mode, the moving amount specifying unit provides the rotating machine control device that specifies the first moving amount that brings a high frequency component that is a frequency component higher than the cutoff angular frequency in the estimated torque close to zero. To do.

  In the second mode, in the first control mode, control is performed to bring the high frequency component, which is a frequency component higher than the cutoff angular frequency in the estimated torque, close to zero. In this way, the estimated vibration component of the torque can be easily brought close to zero.

The third aspect of the present disclosure includes, in addition to the second aspect,
In the first control mode, the first movement amount is specified by feedback control that brings the high-frequency component close to zero,
In the second control mode, there is provided a rotating machine control device in which the first movement amount is specified by feedback control for bringing a difference between the command torque and the estimated torque close to zero.

  In the third mode, in the first control mode, feedback control is performed to bring the high frequency component close to zero. In this way, the estimated vibration component of the torque can be easily brought close to zero. In the third mode, in the second control mode, feedback control is performed so that the difference between the command torque and the estimated torque approaches zero. In this way, the difference between the command torque and the estimated torque can be easily brought close to zero.

In addition to the second aspect or the third aspect, the fourth aspect of the present disclosure includes:
The rotating machine control device includes a command amplitude specifying unit,
In both the first control mode and the second control mode, (i) the same fixed value is used as the command amplitude which is the amplitude of the command magnetic flux vector, or (ii) the value obtained using the same calculation formula is Used as a command amplitude which is the amplitude of the command magnetic flux vector,
In both the first control mode and the second control mode, the command magnetic flux specifying unit provides a rotating machine control device that specifies the command magnetic flux vector using the command amplitude.

  As understood from the first mode, the method for specifying the phase of the command magnetic flux vector (command phase) differs between the first control mode and the second control mode. Depending on the other control in the rotating machine control device and the use conditions of the three-phase rotating machine, if the method of specifying the command magnetic flux vector amplitude (command amplitude) differs greatly between the two control modes, Due to the influence of both differences in the method of specifying the command amplitude, a large torque fluctuation may occur when switching the control mode. In this regard, in the fourth aspect, the common method of specifying the command amplitude in the first control mode and the second control mode is high. For this reason, the 4th mode is advantageous from a viewpoint of torque fluctuation control at the time of control mode change.

The fifth aspect of the present disclosure includes, in addition to the first aspect,
In the first control mode, the movement amount specifying unit is a difference between a low-frequency component that is a frequency component lower than a cutoff angular frequency in the estimated torque and the torque estimated as the low-frequency component. There is provided a rotating machine control device that identifies the first movement amount that brings a first difference close to zero.

  In the fifth aspect, in the first control mode, control is performed so that the first difference, which is the difference between the low frequency component that is a frequency component lower than the cutoff angular frequency in the estimated torque and the estimated torque, approaches zero. Is done. In this way, the estimated vibration component of the torque can be easily brought close to zero.

The sixth aspect of the present disclosure includes, in addition to the fifth aspect,
The rotating machine control device includes a reference torque specifying unit and a command amplitude specifying unit,
The reference torque specifying unit specifies the reference torque that the torque of the three-phase rotating machine should follow when the rotor speed of the three-phase rotating machine follows the command speed,
In the first control mode, the low frequency component is used as the command torque,
In the second control mode, the reference torque is used as the command torque,
In both the first control mode and the second control mode, the first movement amount is specified by feedback control that brings the difference between the command torque and the estimated torque close to zero,
In both the first control mode and the second control mode, the command amplitude specifying unit uses the command torque to specify a command amplitude that is an amplitude of the command magnetic flux vector, and the command magnetic flux specifying unit includes the command amplitude. A rotating machine control device that specifies the command magnetic flux vector using the above is provided.

  In the sixth aspect, in the first control mode, feedback control is performed to bring the same value as the first difference of the fifth aspect close to zero. Therefore, in the first control mode, the first difference can be easily brought close to zero, and the estimated vibration component of the torque can be easily brought close to zero. In the sixth mode, feedback control is performed in the second control mode so that the difference between the command torque and the estimated torque approaches zero. In this way, the difference between the command torque and the estimated torque can be easily brought close to zero.

  The command torque used for specifying the command amplitude in the first control mode of the sixth aspect corresponds to the low frequency component of the torque. For this reason, if the first control mode is used when the rotation speed of the three-phase rotating machine is low, pulsation caused by the low rotation speed is not easily reflected in the command amplitude. For this reason, the pulsation of the specified command amplitude is suppressed, a stable command magnetic flux vector is generated, and the primary magnetic flux vector follows the stable command magnetic flux vector. For this reason, the first control mode of the sixth aspect is advantageous from the viewpoint of performing stable control when the rotational speed is low. Further, due to the stability obtained by the first control mode, torque fluctuation at the time of switching between the first control mode and the second control mode is also alleviated. The command torque used for specifying the command amplitude in the second control mode of the sixth aspect corresponds to the reference torque. The reference torque is related to the torque as well as the low frequency component of the torque. That is, in the sixth aspect, the common method of specifying the command amplitude in the first control mode and the second control mode is high. This high commonality is also advantageous in reducing torque fluctuations when switching control modes.

  Further, the low frequency component of the torque used as the command torque and the reference torque are information useful for specifying the command amplitude. For this reason, in the sixth aspect, in both the first control mode and the second control mode (in both cases where the rotational speed is low and high), it is easy to specify the command amplitude in accordance with the control purpose. For example, maximum torque / current (MTPA) control can be performed in both control modes. This makes it possible to control the three-phase rotating machine with high efficiency both when the rotational speed is low and when the rotational speed is high.

The seventh aspect of the present disclosure includes, in addition to the first aspect,
The movement amount specifying unit has a limiter,
The limiter outputs the upper limit value when the input to the limiter is greater than or equal to an upper limit value, and outputs the lower limit value when the input to the limiter is less than or equal to a lower limit value, and the input to the limiter is When the value is larger than the lower limit value and smaller than the upper limit value, the input to the limiter is output.
In the first control mode, the movement amount specifying unit causes the limiter to input a low frequency component that is a frequency component lower than the cutoff angular frequency in the estimated torque, and the torque estimated as the output of the limiter. The rotating machine control apparatus which specifies the said 1st movement amount which makes the 2nd difference which is a difference close | similar to zero is provided.

  In the seventh aspect, in the first control mode, the low frequency component of the estimated torque is input to the limiter, and control is performed so that the difference between the output of the limiter and the estimated torque (second difference) approaches zero. . In this way, as a result, the estimated vibration component of the torque can be brought close to zero.

  The output of the limiter does not become an extremely small value or an extremely large value. For this reason, according to the limiter, it is possible to avoid a situation in which the current flowing through the three-phase rotating machine becomes excessive. That is, abnormal heat generation in a three-phase rotating machine, an inverter, or the like can be avoided. In this respect, it can be said that the limiter contributes to the realization of a highly reliable rotating machine control device.

The eighth aspect of the present disclosure includes, in addition to the seventh aspect,
The rotating machine control device includes a reference torque specifying unit and a command amplitude specifying unit,
The reference torque specifying unit specifies the reference torque that the torque of the three-phase rotating machine should follow when the rotor speed of the three-phase rotating machine follows the command speed,
In the second control mode, the reference torque is input to the limiter,
In both the first control mode and the second control mode, the output of the limiter is used as the command torque, and the first movement is performed by feedback control that brings the difference between the command torque and the estimated torque close to zero. The quantity is identified,
In both the first control mode and the second control mode, the command amplitude specifying unit uses the command torque to specify a command amplitude that is an amplitude of the command magnetic flux vector, and the command magnetic flux specifying unit includes the command amplitude. A rotating machine control device that specifies the command magnetic flux vector using the above is provided.

  In the eighth mode, in the first control mode, feedback control is performed to bring the same value as the second difference of the seventh mode close to zero. Therefore, in the first control mode, the second difference can be easily brought close to zero, and the estimated vibration component of the torque can be easily brought close to zero. In the eighth mode, feedback control is performed in the second control mode so that the difference between the command torque and the estimated torque approaches zero. In this way, the difference between the command torque and the estimated torque can be easily brought close to zero.

  In the eighth aspect, control using the output of the limiter is performed in both the first control mode and the second control mode. As described above, the output of the limiter does not become an extremely small value or an extremely large value. In the eighth aspect, in both the first control mode and the second control mode, the amplitude of the command magnetic flux vector (command amplitude) is specified using the output of such a limiter. This prevents the command amplitude from becoming extremely small or large. That is, a stable command magnetic flux vector is generated, and the primary magnetic flux vector follows the stable command magnetic flux vector. For this reason, various physical quantities of the three-phase rotating machine such as torque are stabilized as a whole. Such stability also reduces torque fluctuations when switching between the first control mode and the second control mode. Further, the low frequency component of the torque and the reference torque are both related to the torque. In both control modes, the torque related information is input to the limiter, the output of the limiter is used as the command torque, and the command amplitude is calculated from the command torque. Identified. That is, in the eighth aspect, the common method of specifying the command amplitude in both control modes is high. This high commonality is also advantageous in reducing torque fluctuations when switching control modes.

  When the input to the limiter is larger than the lower limit value and smaller than the upper limit value in the first control mode and the second control mode of the seventh and eighth modes, the fifth and fifth modes are performed according to the seventh and eighth modes. The same effect as in the sixth aspect can be obtained.

The ninth aspect of the present disclosure is:
A rotating machine control method for applying a voltage vector to the three-phase rotating machine using an inverter so that a primary magnetic flux vector of the three-phase rotating machine follows the command magnetic flux vector,
The rotating machine control method can switch between a second control mode in which the torque of the three-phase rotating machine follows the command torque and a first control mode different from the second control mode,
The rotating machine control method includes:
A torque estimation step of estimating a torque of the three-phase rotating machine using the primary magnetic flux vector and a current vector of the three-phase rotating machine;
A phase estimating step for estimating a phase of the primary magnetic flux vector;
The product of the command speed of the three-phase rotating machine and the cycle of the control cycle is calculated, and the estimated vibration component of the torque is approximated to zero in the first control mode, and the command in the second control mode. By identifying a first movement amount that approximates the difference between the torque and the estimated torque to zero, and summing the product and the first movement amount, the phase of the primary magnetic flux vector is determined in one control cycle. A movement amount specifying step for specifying a second movement amount to be moved;
A command phase specifying step of specifying a command phase that is a phase of the command magnetic flux vector using the estimated phase and the second movement amount;
There is provided a rotating machine control method comprising: a command magnetic flux specifying step for specifying the command magnetic flux vector using the command phase.

  According to the ninth aspect, the same effect as that of the first aspect can be obtained.

  The technology of the rotating machine control device can be applied to a rotating machine control method. The technology of the rotating machine control method can be applied to the rotating machine control device.

  A tenth aspect of the present disclosure provides a computer program including instructions for executing the rotating machine control method of the ninth aspect.

  An eleventh aspect of the present disclosure provides a computer-readable memory storing the computer program according to the tenth aspect.

  A twelfth aspect of the present disclosure provides a processor that executes the computer program of the tenth aspect.

The thirteenth aspect of the present disclosure includes
A computer-readable memory storing the computer program of the tenth aspect;
A control system comprising a processor for executing the computer program is provided.

  Hereinafter, embodiments of the present disclosure will be described in detail based on the drawings.

  As illustrated in FIG. 1, the rotating machine control device 100 (, 200a, 200b) of the present disclosure includes a first current sensor 105a, a second current sensor 105b, a rotating machine control unit 101 (, 201a, 201b), and a duty generation unit. 103 is included. The rotating machine control device 100 can be connected to a PWM inverter (a power conversion circuit that performs power conversion by a PWM method) 104 and a three-phase rotating machine 102.

  The rotating machine control unit 101 has a configuration for driving the three-phase rotating machine 102 at a desired command speed. The rotating machine control unit 101 is configured to execute speed / position sensorless operation of the three-phase rotating machine 102. The speed / position sensorless operation is an operation that does not use a position sensor such as an encoder or a resolver. In the sensorless operation of the present embodiment, the magnetic flux vector of the three-phase rotating machine 102 is estimated. Then, the magnetic flux vector is controlled using the estimated phase of the magnetic flux vector. The magnetic flux vector is a concept including both the armature linkage magnetic flux on the three-phase AC coordinate applied to the three-phase rotating machine 102 and the magnetic flux obtained by coordinate conversion of this armature linkage flux. Similarly, the current vector is a concept including both a current vector on a three-phase AC coordinate flowing through the three-phase rotating machine 102 and a current vector obtained by coordinate conversion of the current vector. Similarly, the voltage vector is a concept including both a voltage vector on a three-phase AC coordinate applied to the three-phase rotating machine 102 and a voltage vector obtained by coordinate conversion of the voltage vector. In this specification, “amplitude” may simply refer to magnitude (absolute value).

  Some or all elements of the rotating machine control device 100 may be provided by a control application executed in a DSP (Digital Signal Processor) or a microcomputer. The DSP or microcomputer may include peripheral devices such as a core, a memory, an A / D conversion circuit, and a communication port. Further, some or all of the elements of the rotating machine control device 100 may be configured by a logic circuit.

(Outline of control using the rotating machine control device 100)
An outline of control using the rotating machine control device 100 will be described with reference to FIG. The phase currents i _u and i _w are detected by the current sensors 105a and 105b. The phase currents i _u and i _w collectively describe the U-phase current i _u and the W-phase current i _w . U-phase current i _u and the W-phase current i _w is the U-phase component and a W-phase component of the current vector i _a respectively detected. The rotating machine control unit 101 specifies command voltage vectors v _u ^* , v _v ^* , v _w ^* from the command speed ω _ref ^* and the phase currents i _u , i _w . Each component of the command voltage vectors v _u ^* , v _v ^* , v _w ^* corresponds to a U-phase voltage, a V-phase voltage, and a W-phase voltage on a three-phase AC coordinate, respectively. The duty generation unit 103, the command voltage vector _{v u} ^*, v v ^*, the v _w ^*, the duty D _u, D _v, D _w is generated. The PWM inverter 104 generates voltage vectors v _u , v _v , v _w to be applied to the three-phase rotating machine 102 from the duties D _u , D _v , D _w . The command speed ω _ref ^* is given to the rotating machine control device 100 from the host control device. The command speed ω _ref ^* represents the rotation speed (unit: rad / sec) that the rotation speed of the three-phase rotating machine 102 should follow. By such control, the three-phase rotating machine 102 is controlled such that the rotation speed follows the command speed ω _ref ^* .

The command voltage vectors v _u ^* , v _v ^* , v _w ^* are updated sequentially. In the present specification, a cycle from the update of the command voltage vectors v _u ^* , v _v ^* , v _w ^* to the next update is referred to as a “control cycle”. In the present embodiment, the command torque and the command voltage vectors v _u ^* , v _v ^* , v _w ^* are specified for each control cycle. The specified command voltage vectors v _u ^* , v _v ^* , v _w ^* define the voltage vectors v _u , v _v , v _w applied to the three-phase rotating machine 102 in the next control cycle. Each control cycle of the present embodiment has a period T _s .

  The dq coordinate system shown in FIG. 2A is a rotating coordinate system. The d-axis and the q-axis rotate at the same speed as the rotational speed (angular speed) of the rotor magnetic flux vector (secondary magnetic flux vector). The counterclockwise direction is the phase advance direction. The d-axis is set as an axis extending in the direction of the rotor magnetic flux vector. The q-axis is set as an axis obtained by rotating the d-axis by 90 degrees in the advance direction. The U axis corresponds to the U phase winding. The V axis corresponds to the V phase winding. The W axis corresponds to the W phase winding. The U-axis, V-axis, and W-axis do not rotate even when the rotor rotates. That is, the U axis, the V axis, and the W axis are fixed axes.

The rotor speed ω _2n represents the speed of the rotor (not shown). The secondary magnetic flux rotational speed ω _2f represents the rotational speed of the secondary magnetic flux vector. In the case of an asynchronous machine such as an induction machine, there is a difference between the rotor speed (rotor speed) ω _2n and the secondary magnetic flux speed ω _2f , and this difference is called the slip angular speed ω _s . In this specification, unless otherwise specified, an angle means an electrical angle. The angle between the d-axis and the q-axis, the angle θ, the rotor angular velocity ω _2n, and the secondary magnetic flux rotational velocity ω _2f are values based on the electrical angle. The unit of the rotor speed ω _2n and the secondary magnetic flux rotation speed ω _2f is rad / sec.

  The αβ coordinate system shown in FIG. 2B is a fixed coordinate system. The α axis and the β axis are fixed axes. The counterclockwise direction is the phase advance direction. The α axis is set as an axis extending in the same direction as the U axis. The β axis is set as an axis obtained by rotating the α axis by 90 degrees in the advance direction.

(Embodiment 1)
(About the rotating machine control unit 101)
As shown in FIG. 3, the rotating machine control unit 101 includes a u, w / α, β conversion unit (three-phase two-phase coordinate conversion unit) 106, a command voltage identification unit 107, a magnetic flux estimation unit 108, a torque estimation unit 109, Speed / phase estimation unit 110, reference torque specifying unit 121, command amplitude specifying unit 122, movement amount specifying unit 111, command phase specifying unit 127, command magnetic flux specifying unit 112, α-axis magnetic flux deviation specifying unit 113a, β-axis magnetic flux deviation specifying Part 113b and α, β / u, v, w converter (two-phase three-phase coordinate converter) 114.

In the rotating machine control unit 101, the phase currents i _u and i _w are converted into axial currents i _α and i _β by the u, w / α, β conversion unit 106. The axial currents i _α and i _β are collectively described as the α-axis current i _α and the β-axis current i _β on the α-β coordinate of the three-phase rotating machine 102. Since the phase currents i _u and i _w and the shaft currents i _α and i _β are current vectors, the phase currents i _u and i _w and the shaft currents i _α and i _β are respectively _converted into the current vectors i _u and i _w and the current vector i. _α and i _β can be referred to. The magnetic flux estimation unit 108 estimates the primary magnetic flux vector of the three-phase rotating machine 102 from the command shaft voltages v _α ^* , v _β ^* and the shaft currents i _α , i _β (the estimated primary magnetic flux ψ _s is specified). . Estimated to as primary magnetic flux [psi respectively estimated primary flux of alpha-axis component and beta-axis component of _s [psi _alpha and estimated primary flux [psi _beta. The amplitude of the estimated primary magnetic flux ψ _s is described as | ψ _s |. The shaft command voltages v _α ^* and v _β ^* define a voltage vector applied to the rotating machine in the next control cycle. The speed / phase estimation unit 110 estimates the phase of the primary magnetic flux vector of the three-phase rotating machine 102 and the rotational speed of the primary magnetic flux from the estimated primary magnetic fluxes ψ _α and ψ _β (the estimated phase θ _s and the estimated primary magnetic flux velocity). ω _1f is specified). In the example of FIG. 3, the rotational speed of the primary magnetic flux and the rotational speed of the rotor are the same. That is, the estimated rotor speed ω _2n is specified by the speed / phase estimation unit 110. The torque estimation unit 109 estimates the torque of the three-phase rotating machine 102 from the estimated primary magnetic fluxes ψ _α , ψ _β and the shaft currents i _α , i _β (the estimated torque _Te is specified). The reference torque specifying unit 121 specifies the reference torque T _ref so that the estimated rotor speed ω _2n matches the command speed ω _ref ^* . By the movement amount determination section 111, the reference torque T _ref, the command velocity omega _ref ^* and the estimated torque T _e, the second movement amount [Delta] [theta] _s are identified. The command amplitude specifying unit 122 specifies the command amplitude | ψ _s ^* | from the reference torque T _ref . The command phase identification unit 127 identifies the command phase θ _s ^* from the second movement amount Δθ _s and the estimated phase θ _s . The command magnetic flux specifying unit 112 specifies the command magnetic flux vector ψ _s ^* from the command phase θ _s ^* and the command amplitude | ψ _s ^* |. The α-axis component and β-axis component of the command magnetic flux vector ψ _s ^* are described as α-axis command magnetic flux ψ _α ^* and β-axis command magnetic flux ψ _β ^* , respectively. The deviation (flux deviation Δψ _α = ψ _α ^* −ψ _α ) between the α-axis command magnetic flux ψ _α ^* and the estimated primary magnetic flux ψ _α is obtained by the α-axis magnetic flux deviation specifying unit 113a. the beta-axis magnetic flux deviation particular portion 113b, beta axis command flux [psi _beta ^* and the estimated primary flux [psi _beta and deviation (the magnetic flux deviation ^{_{Δψ β = ψ β * -ψ β}} ) is obtained. The command voltage specifying unit 107 specifies the command shaft voltages v _α ^* and v _β ^* from the magnetic flux deviations Δψ _α and Δψ _β and the shaft currents i _α and i _β . The command axis voltages v _α ^* and v _β ^* are a summary of the α axis command voltage v _α ^* and the β axis command voltage v _β ^* on the α-β coordinate of the three-phase rotating machine 102. Since the command axis voltages v _α ^* and v _β ^* are voltage vectors, the command axis voltages v _α ^* and v _β ^* can be referred to as command voltage vectors v _α ^* and v _β ^* . The α, β / u, v, w conversion unit 114 converts the command axis voltages v _α ^* , v _β ^* into command voltage vectors v _u ^* , v _v ^* , v _w ^* . In this embodiment, in the first control mode described later, the reference torque specifying unit 121 and the command amplitude specifying unit 122 do not function, and the movement amount specifying unit 111 does not use the reference torque T _ref .

By such control (feedback control), the primary magnetic flux vector of the three-phase rotating machine 102 follows the command magnetic flux vector ψ _s ^* (the amplitude of the primary magnetic flux vector of the three-phase rotating machine 102 becomes the command amplitude | ψ _s ^* | The voltage vector is applied to the three-phase rotating machine 102 via the PWM inverter 104.

In the present specification, the shaft currents i _α and i _β mean current values transmitted as information, not currents actually flowing through the three-phase rotating machine 102. Command shaft voltage v _α ^* , v _β ^* , estimated primary magnetic flux ψ _s (magnetic flux ψ _α , ψ _β ), estimated phase θ _s , estimated torque T _e , reference torque T _ref , command torque T _e ^* , command speed ω _ref ^The same applies to ^* , command phase θ _s ^* , command amplitude | ψ _s ^* |, command magnetic flux vector ψ _s ^* , command voltage vectors v _u ^* , v _v ^* , v _w ^{*, and the} like.

  Each component regarding control of this embodiment is explained below.

(First current sensor 105a, second current sensor 105b)
The first current sensor 105a and the second current sensor 105b detect phase currents (current vectors) i _u and i _w of the three-phase rotating machine 102. As the first current sensor 105a and the second current sensor 105b shown in FIG. 1, known current sensors can be used. In the present embodiment, the first current sensor 105a is provided to measure the phase current i _u flowing through the u phase. The second current sensor 105b is provided to measure the phase current i _w flowing through the w phase. However, the first current sensor 105a and the second current sensor 105b may be provided so as to measure a two-phase current of a combination other than the u-phase and w-phase two phases. Hereinafter, the combination of the first current sensor 105a and the second current sensor 105b may be referred to as a current detection unit. Current detector detects a current vector i _a.

(U, w / α, β converter 106)
The u, w / α, β converter 106 shown in FIG. 3 converts the phase currents i _u , i _w into axial currents i _α , i _β . Specifically, the u, w / α, β conversion unit 106 converts the phase currents i _u , i _w into axial currents i _α , i _{β according} to equations (1-1) and (1-2), The shaft currents i _α and i _β are output.

(Magnetic flux estimation unit 108)
The magnetic flux estimation unit 108 estimates the primary magnetic flux vector of the three-phase rotating machine 102 in the current control cycle using the command shaft voltages (command voltage vectors) v _α ^* and v _β ^* specified in the previous control cycle. (The estimated primary magnetic flux ψ _s is specified). Specifically, the magnetic flux estimation unit 108 obtains an estimated primary magnetic flux ψ _s (estimated primary magnetic flux ψ _α , ψ _β ) from the shaft currents i _α and i _β and the command shaft voltages v _α ^* and v _β ^* . More specifically, the magnetic flux estimation unit 108 uses the equations (1-3), (1-4), and (1-5) to calculate the estimated primary magnetic fluxes ψ _α and ψ _β and the estimated primary magnetic flux ψ _s . Determine the amplitude | ψ _s |. Equation (1-3) and (1-4) in _{ψ α | t = 0, ψ} β | t = 0 , respectively estimated primary flux [psi _alpha, which is the initial value of [psi _beta. R _a in the expressions (1-3) and (1-4) is _a stator resistance of the three-phase rotating machine 102. In the present embodiment, the integrator required for the calculations in equations (1-3) and (1-4) is configured as a discrete system.

When the estimated primary magnetic flux ψ _s is specified, the detected voltage vector (two-phase voltage v _αβ ) of the three-phase rotating machine 102 can be used instead of the command voltage vector (command shaft voltage v _αβ ^* ). That is, “v _α ^* ” in equation (1-3) can be replaced with “v _α ”, and “v _β ^* ” in equation (1-4) can be replaced with “v _β ”. Specifically, the magnetic flux estimation unit 108 performs estimation using a two-phase voltage (two-phase voltage v _αβ ) obtained by three-phase to two-phase conversion of a detected voltage vector applied to the three-phase rotating machine 102. The primary magnetic flux ψ _s may be specified.

(Torque estimation unit 109)
The torque estimation unit 109 calculates the current current value i _a (axis current i _α , i _β ) and the estimated primary magnetic flux vectors ψ _α and ψ _β that are the primary magnetic flux vectors estimated in the current control cycle from the current The torque in the control cycle is estimated (estimated torque _Te is specified). Specifically, the torque estimation unit 109, using Equation (1-6), obtaining the estimated torque T _e. N _p in Expression (1-6) is the number of pole pairs of the three-phase rotating machine 102.

(Velocity / phase estimation unit 110)
The speed / phase estimation unit 110 estimates the phase of the primary magnetic flux vector (specifies the estimated phase θ _s ) from the estimated primary magnetic flux ψ _s (estimated primary magnetic flux ψ _α , ψ _β ). Specifically, the speed / phase estimation unit 110 obtains the estimated phase θ _s by Expression (1-7). Further, the speed / phase estimation unit 110 uses the estimated phase θ _s (n) obtained in the current control cycle and the estimated phase θ _s (n−1) obtained in the previous control cycle, to obtain the equation (1). -8), the angular velocity ω _{1f of the} primary magnetic flux of the three-phase rotating machine 102, that is, the angular velocity (rotor velocity) ω _2n of the rotor is estimated. Since the three-phase rotating machine 102 of the present embodiment is a synchronous rotating machine as will be described later, the angular velocity ω _{1f of the} primary magnetic flux coincides with the angular velocity ω _2n of the rotor. The speed / phase estimation unit 110 is a known speed / phase estimator. Here, T _s means the period of each control cycle (control period). n indicates the nth control cycle. n is an integer.

When the three-phase rotating machine 102 is an induction machine, the angular velocity ω _2n of the rotor is an angular velocity shifted by the slip angular velocity ω _{s from} the rotational velocity ω _{1f of the} primary magnetic flux. For this reason, the rotor speed ω _2n cannot be obtained from the equation (1-8). In the modification in which the three-phase rotating machine 102 is an induction machine, the rotational speed ω _{1f of the} primary magnetic flux of the three-phase rotating machine 102 obtained using the relational expression between the left side and the middle side of the formula (1-8), normalized rotor flux [psi _2n, from the estimated torque T _e, for estimating the speed of the rotor (specifying the rotor speed omega _2n). Specifically, the slip angular velocity ω _s is obtained using Expression (1-9A). Further, the rotor speed ω _2n is obtained from the calculated slip angular speed ω _s and the primary magnetic flux rotational speed ω _1f by the equation (1-10). R _2n in the formula (1-9A) is a normalized rotor resistance of the three-phase induction machine 102. M is a mutual inductance. R ₂ is the rotor resistance. L ₂ is the rotor inductance. Note that the normalized secondary magnetic flux ψ _2n is M / L ₂ times the rotor magnetic flux (secondary magnetic flux) ψ ₂ , and the rotational speed of the normalized secondary magnetic flux ψ _{2n is} the rotational speed of the secondary magnetic flux ψ ₂ . Is the same. The derivation method of the formula (1-9A) is, for example, a known document (Shinji Shinnaka: “Sensorless vector control of an induction motor using a minimum-dimensional D-factor magnetic flux state observer accompanied by instantaneous speed estimation”, IEEJ Transaction D Vol.135, No.3, pp.299-307, (2015)). It is also described in the above-mentioned known literature that the rotation speed ω _1f of the primary magnetic flux can be used instead of the rotation speed ω _2f of the secondary magnetic flux (normalized secondary magnetic flux) under the condition that the norm of the normalized secondary magnetic flux ψ _2n is constant. It is as follows. The normalized secondary magnetic flux ψ _2n can be obtained using, for example, the formula (1-9B). L _1t i _a in the formula (1-9B) is a virtual armature reaction magnetic flux of the three-phase induction machine 102. l _1t is the stator total leakage inductance. Will be described in detail later virtual armature reaction flux l _1t i _a and the stator total leakage inductance.

  In the present embodiment, the speed / phase estimation unit 110 includes a speed estimation unit (speed identification unit) and a phase estimation unit (phase identification unit). These may be combined to form a single estimation unit, or may be provided separately.

(Reference torque specifying unit 121)
The reference torque specifying unit 121 specifies the reference torque T _ref from the command speed ω _ref ^* and the estimated rotor speed ω _2n . Specifically, the reference torque specifying unit 121 obtains the reference torque T _{ref according} to the equation (1-11). K _sp in equation (1-11) is a proportional gain. K _sI is an integral gain. The reference torque specifying unit 121 is a known PI compensator. In the present embodiment, the reference torque specifying unit 121 operates in a second control mode described later and does not operate in the first control mode. This is the same in the second and third embodiments. However, if necessary, the reference torque specifying unit 121 may be operated in the first control mode.

(Movement amount specifying unit 111)
The movement amount specifying unit 111 obtains the second movement amount Δθ _s from the reference torque T _ref , the estimated torque _Te and the command speed ω _ref ^* . The second movement amount Δθ _s is a movement amount that the phase of the primary magnetic flux vector should move in one control cycle. As illustrated in FIG. 4, the movement amount specifying unit 111 includes a torque subtracting unit 141, a high-pass filter (HPF) 142, a multiplying unit 143, a changeover switch 144, a PI compensator 145, a multiplying unit 146, and an addition Part 147.

The movement amount specifying unit 111 can switch between the first control mode and the second control mode by switching the changeover switch 144. The first control mode is a control mode in which a decrease in control performance can be suppressed when the rotation speed of the three-phase rotating machine 102 is low. The second control mode is a control mode that can ensure high responsiveness to torque when the rotational speed is high. In the second control mode, the rotating machine control device 102 causes the torque of the three-phase rotating machine 102 to follow the command torque _Te ^* (which is the same as the reference torque _Tref in this embodiment).

In the first control mode, HPF142 extracts a high frequency component of the estimated torque T _e (specific). Next, the multiplication unit 143 inverts the sign of the high frequency component. Thus, (variation in torque) vibration component of the estimated torque T _e [Delta] T ₁ is obtained. The operations of the HPF 142 and the multiplication unit 143 are expressed by Expression (1-12). In Expression (1-12), ω _c is a cutoff angular frequency.

Next, in the first control mode, the changeover switch 144 selects the vibration component ΔT ₁ . Next, the PI compensator 145 specifies the first movement amount Δθ based on the equation (1-13A). In the equation (1-13A), _KθP is a proportional gain. K _θI is an integral gain. In this embodiment, the integrator required for the calculation in Expression (1-13A) is configured as a discrete system. As can be understood from the equation (1-13A), the PI compensator 145 performs feedback control that makes the input to itself approach zero (specifically, converges), thereby specifying the first movement amount Δθ. It functions as a compensation unit (this is the same in the second control mode of the first embodiment and the first and second control modes of the second and third embodiments). In the first control mode, the vibration component ΔT ₁ approaches zero by feedback control performed by the PI compensator 145. As a result, the output of HPF 142 also approaches zero. Also in the second and third embodiments, similar embodiment 1, the first movement amount Δθ in the first control mode is generated so as to approach the vibration component of the estimated torque T _e to zero.

In the first control mode, the multiplication unit 146 identifies the product ω _ref ^* T _s by multiplying the command speed ω _ref ^* by the control period T _s . The adding unit 147 adds the first movement amount Δθ and the product ω _ref ^* T _s . Thus, the second movement amount (movement amount of the primary magnetic flux vector) Δθ _s is specified. The operations of the multiplying unit 146 and the adding unit 147 are expressed by Expression (1-14).

Thus, in a first control mode, the movement amount determination unit 111 determines a first movement amount Δθ to approximate the high-frequency component is a frequency component higher than the cutoff angular frequency omega _c in the estimated torque T _e to zero. Then, the second movement amount Δθ _s is specified by summing the first movement amount Δθ and the product ω _ref ^* T _s .

In the second control mode, the torque subtraction unit 141, using the reference torque T _ref as the command torque T _e ^*, by subtracting the estimated torque T _e from the command torque T _e ^*, the torque deviation [Delta] T ₂ (= T _e ^* - T _e ) is specified. Next, the changeover switch 144 selects the torque deviation ΔT ₂ . Next, the PI compensator 145 specifies the first movement amount Δθ based on the equation (1-13B). As it can be understood from formula (1-13B), the first movement amount Δθ in the second control mode, the command torque T _e ^* (in the present embodiment is the same as the reference torque T _ref) and the estimated torque T _e Is close to zero.

Thereafter, in the second control mode, the multiplying unit 146 identifies the product ω _ref ^* T _s by multiplying the command speed ω _ref ^* by the control period T _s . The adding unit 147 obtains the second movement amount Δθ _s by adding the first movement amount Δθ and the product ω _ref ^* T _s . The operations of the multiplying unit 146 and the adding unit 147 in the second control mode are also expressed by the above equation (1-14).

A control mode switching method according to the present embodiment will be described with reference to FIG. Of the two half lines extending in the left-right direction in FIG. 5, the lower half line corresponds to the first control mode, and the upper half line corresponds to the second control mode. As shown in FIG. 5, when the three-phase rotating machine 102 accelerates and the rotor speed ω _2n becomes equal to or higher than ω _th2 in the state where the first control mode is selected, the control mode is switched to the second control mode. When the second control mode is selected, when the three-phase rotating machine 102 decelerates and the rotor speed ω _2n becomes equal to or less than ω _th1 , the control mode is switched to the first control mode. These switches are performed by the switch 144.

In the region where the rotation speed of the three-phase rotating machine 102 is low, it is difficult to ensure the estimation accuracy of the rotor speed. Since the reference torque T _ref is generated based on the estimated rotor speed ω _2n , it is difficult to ensure the accuracy of the reference torque T _ref . In this regard, in the present embodiment, when the rotation speed is low, the first control mode is selected, and the second movement amount Δθ _s is specified without using the reference torque T _ref . Thereby, stability at the time of low-speed driving of the three-phase rotating machine 102 is ensured. On the other hand, when the rotational speed is high, the second control mode is selected, and the second movement amount Δθ _s is specified using the reference torque T _ref . Thereby, the high responsiveness with respect to a torque is ensured.

  As can be understood from the description using FIG. 5, the relationship between the rotation speed of the three-phase rotating machine 102 and the control mode switching timing constitutes a hysteresis loop. According to such a hysteresis loop, chattering at the time of control mode switching can be prevented.

Note that inversion of the sign of the high-frequency component by the multiplier 143 is not essential. That is, the multiplication unit 143 can be omitted. It can be considered that the high frequency component itself is a vibration component. Even when this omission is performed, it is possible to configure the movement amount specifying unit 111 such that an appropriate second movement amount Δθ _s can be obtained.

(Command phase specifying unit 127)
The command phase identification unit 127 identifies the command phase θ _s ^* from the second movement amount (movement amount of the primary magnetic flux vector) Δθ _s and the estimated phase θ _s . The command phase θ _s ^* is the phase of the command magnetic flux vector ψ _s ^* . Specifically, the command phase specifying unit 127 obtains the command phase θ _s ^* using the equation (1-15).

(Command amplitude specifying unit 122)
The amplitude command generator 122 is configured to use the reference torque T _ref as the command torque T _e ^{* and} to specify the command amplitude | ψ _s ^* | from the command torque T _e ^* . The command amplitude | ψ _s ^* | is the amplitude of the command magnetic flux vector ψ _s ^* . The command amplitude specifying unit 122 can be configured using a lookup table, an operator storing a calculation formula (approximation formula), or the like. When using a look-up table, a look-up table representing the correspondence between the command torque T _e ^* and the command amplitude | ψ _s ^* | can be prepared in advance. Calculation formulas for operators can also be prepared in advance. Such a lookup table and calculation formula can be set based on measurement data or theory performed in advance. The specific method of specifying the command amplitude | ψ _s ^* | is known in the literature (Yoji Takeda, Shigeo Morimoto, Nobuyuki Matsui, Yukio Honda, “Design and Control of an Embedded Magnet Synchronous Motor”, Ohm Corporation, 2001. Reference is made to October 25, etc.). In this embodiment, the relationship between the torque and the magnetic flux satisfying the maximum torque / current control (MTPA) that can generate the maximum torque with the minimum current is used. The command amplitude specifying unit 122 in the present embodiment obtains the command amplitude | ψ _s ^* | using the magnetic flux parameter | ψ _a |. The magnetic flux parameter | ψ _a | is a constant given as the amplitude of the magnetic flux generated by the permanent magnet in the three-phase rotating machine (synchronous rotating machine in this embodiment) 102.

In the first embodiment, the command amplitude | ψ _s ^* | is specified by the command amplitude specifying unit 122 in the second control mode. In the first control mode, the command amplitude | ψ _s ^* | is obtained without using the command amplitude specifying unit 122. Specifically, in the first control mode, a fixed value or a value obtained using a calculation formula is used as the command amplitude | ψ _s ^* |. However, if necessary, the command amplitude | ψ _s ^* | may be specified by the command amplitude specifying unit 122 also in the first control mode of the first embodiment.

In the modification of the first embodiment, in both the first control mode and the second control mode, (i) the same fixed value is used as the command amplitude | ψ _s ^* |, or (ii) obtained using the same calculation formula. Is used as the command amplitude | ψ _s ^* |. In this modification, the common method of specifying the command amplitude in the first control mode and the second control mode is high. For this reason, this modification is advantageous from the viewpoint of torque fluctuation suppression at the time of control mode switching. An example of the calculation formula (ii) will be described in the item “Example of calculation formula for obtaining command amplitude | ψ _s ^* |” described later. This calculation formula can also be used to specify the command amplitude | ψ _s ^* | in the first control mode even when the command amplitude specifying unit 122 is used in the second control mode.

In the second and third embodiments described later, the command amplitude | ψ _s ^* | is specified by the command amplitude specifying unit 122 in both the first control mode and the second control mode. However, also in the second embodiment and the third embodiment, the above-mentioned fixed values or calculation formulas may be used in the first control mode and / or the second control mode.

(Command magnetic flux specifying unit 112)
The command magnetic flux specifying unit 112 specifies the command magnetic flux vector ψ _s ^* using the command phase θ _s ^* and the command amplitude | ψ _s ^* | for each control cycle. The specified command magnetic flux vector ψ _s ^* defines a primary magnetic flux vector applied to the three-phase rotating machine 102 in the next control cycle. Specifically, the command magnetic flux vectors ψ _α ^* and ψ _β ^* are obtained using equations (1-16) and (1-17). The command magnetic flux ψ _α ^* is an α-axis component of the command magnetic flux vectors ψ _α ^* and ψ _β ^* . The command magnetic flux ψ _β ^* is a β-axis component of the command magnetic flux vectors ψ _α ^* , ψ _β ^* .

  Note that the command amplitude specifying unit 122, the command phase specifying unit 127, and the command magnetic flux specifying unit 112 may constitute one united calculation unit.

(Α-axis magnetic flux deviation specifying unit 113a, β-axis magnetic flux deviation specifying unit 113b)
alpha -axis magnetic flux deviation identifying unit 113a acquires the command flux [psi _alpha ^* and the estimated primary flux [psi _alpha, these deviations (the magnetic flux deviation ^{_{Δψ α: ψ α * -ψ α}} ) obtained. beta-axis magnetic flux deviation identifying unit 113b acquires the command flux [psi _beta ^* and the estimated primary flux [psi _beta, these deviations (the magnetic flux deviation ^{_{Δψ β: ψ β * -ψ β}} ) obtained. As the magnetic flux deviation specifying parts 113a and 113b, known operators can be used.

(Command voltage specifying unit 107)
The command voltage specifying unit 107 specifies the command axis voltage (command voltage vector) v _α ^* , v _β ^* for each control cycle. The specified command axis voltages v _α ^* and v _β ^* define a voltage vector applied to the three-phase rotating machine 102 in the next control cycle. Specifically, the command voltage specifying unit 107 obtains command shaft voltages v _α ^* and v _β ^* from the magnetic flux deviations Δψ _α and Δψ _β and the shaft currents i _α and i _β . More specifically, the command voltage specifying unit 107 obtains the α-axis command voltage v _α ^* using the equation (1-18), and obtains the β-axis command voltage v _β ^* using the equation (1-19). .

(Α, β / u, v, w converter 114)
The α, β / u, v, w conversion unit 114 converts the command axis voltages v _α ^* , v _β ^* into command voltage vectors v _u ^* , v _v ^* , v _w ^* . Specifically, the α, β / u, v, w conversion unit 114 converts the command axis voltages v _α ^* , v _β ^* into the command voltage vectors v _u ^* , v _v ^* , v _w according to Expression (1-20). ^The command voltage vectors v _u ^* , v _v ^* , v _w ^* are output after being converted to ^* .

(Duty generator 103)
Duty generation unit 103 shown in FIG. 1, the command voltage vector _{^{v u *, v v *,}} v from _w ^*, the duty D _u, D _v, to produce a D _w. In the present embodiment, the duty generation unit 103 converts each component of the command voltage vectors v _u ^* , v _v ^* , and v _w ^* into the duty _Du , D _v , and D _w of each phase. As a method for generating the duties D _u , D _v , and D _w, a method used for a general voltage source PWM inverter can be used. For example, the duty D _u, D _v, D _w is the command voltage vector _{v u} ^*, v v ^*, and v _w ^*, by dividing in half the value of the voltage value V _dc of the DC power supply 118 (FIG. 6) You may ask for it. In this case, the duty _Du is 2 ^* _vu ^* / _Vdc . The duty D _v is 2 × v _v ^* / V _dc . The duty D _w is 2 × v _w ^* / V _dc . Duty generation unit 103, duty D _u, D _v, and outputs the D _w.

(PWM inverter 104)
As shown in FIGS. 1 and 6, the PWM inverter 104 includes a conversion circuit in which switching elements 119a, 119b, 119c, 119d, 119e, and 119f and freewheeling diodes 120a, 120b, 120c, 120d, 120e, and 120f are paired. A base driver 116, a smoothing capacitor 117, and a DC power supply 118 are included. The DC power supply 118 represents an output rectified by a diode bridge or the like.

The PWM inverter 104 applies a voltage vector to the three-phase rotating machine 102 by PWM control. Specifically, power is supplied to the three-phase rotating machine 102 from the DC power source 118 via the switching elements 119a to 119f. More specifically, first, the duty D _u, D _v, D _w is input to the base driver 116. Then, the duty D _u, D _v, D _w is converted into a drive signal for electrically driving the switching elements 119A～119f. Next, each of the switching elements 119a to 119f operates according to the drive signal.

  In the present embodiment, the PWM inverter 104 is a three-phase switching circuit using switching elements 119a to 119f. Examples of the switching elements 119a to 119f include a MOSFET (Metal Oxide Semiconductor Field Effect Transistor) and an IGBT (Insulated Gate Bipolar Transistor).

  The rotating machine control device 100 of this embodiment applies a voltage vector to the three-phase rotating machine 102 using the PMW inverter 104. Specifically, the rotating machine control device 100 uses the PMW inverter 104 to supply, to the three-phase rotating machine 102, a voltage vector having an average value of the command voltage vector for the current control cycle specified in the previous control cycle. Apply.

(3-phase rotating machine 102)
A three-phase rotating machine 102 illustrated in FIG. 1 is a control target of the rotating machine control device 100. The three-phase rotating machine 102 may be an electric motor or a generator. A voltage vector is applied to the three-phase rotating machine 102 by the PWM inverter 104. “A voltage vector is applied to the three-phase rotating machine 102” means that a voltage is applied to each of the three phases (U phase, V phase, W phase) on the three-phase AC coordinate in the three-phase rotating machine 102. Point to. In the present embodiment, each of the three phases (U phase, V phase, W phase) is selected from two types: a high voltage phase having a relatively high voltage and a low voltage phase having a relatively low voltage. The three-phase rotating machine 102 is controlled so as to be one of the following.

  The three-phase rotating machine 102 in the present embodiment is, for example, a permanent magnet synchronous rotating machine. Examples of the permanent magnet synchronous rotating machine include IPMSM (Interior Permanent Magnet Synchronous Motor) and SPMSM (Surface Permanent Magnet Synchronous Motor). The IPMSM has a saliency in which the d-axis inductance Ld and the q-axis inductance Lq are different (generally, a reverse saliency of Lq> Ld), and a reluctance torque can be used in addition to the magnet torque. For this reason, the driving efficiency of the IPMSM is extremely high. As the three-phase rotating machine 102, an induction machine or a synchronous reluctance motor can also be used.

(Effect of this embodiment)
When the rotation speed of the three-phase rotating machine 102 is low, it is difficult to ensure the estimation accuracy of the rotor speed, and therefore it is difficult to ensure the accuracy of the reference torque T _ref . In this regard, in the first control mode of the present embodiment, the second movement amount Δθ _s is specified without using the reference torque T _ref . For this reason, the first control mode is suitable for stabilizing the driving of the three-phase rotating machine 102 (to ensure robustness) when the rotation speed of the three-phase rotating machine 102 is low. In the first control mode of the present embodiment, the vibration component [Delta] T ₁ of the estimated torque T _e close to zero (specifically to converge to zero) the first movement amount Δθ is identified. A first movement amount Δθ is reflected to the command flux vector [psi _s ^* phase (command phase) θ _s ^*, the command flux vector [psi _s ^* to the primary flux vector to follow. The information of the vibration component [Delta] T ₁ of the estimated torque T _e is reflected in the command phase theta _s ^* helps to stabilize the driving of the 3-phase rotating machine 102. For this reason, according to the first control mode, even when the rotation speed of the three-phase rotating machine 102 is low, the control performance is unlikely to deteriorate.

In the second control mode of this embodiment, with reference torque T _ref as the command torque T _e ^*, the command torque T _e ^* and close the difference between the estimated torque to zero (specifically to converge to zero) first The movement amount Δθ is specified. A first movement amount [Delta] [theta] is reflected in the second movement amount [Delta] [theta] _s, the second movement amount [Delta] [theta] _s is reflected to the command flux vector [psi _s ^* phase (command phase) θ _s ^*, the command flux vector [psi _s ^The primary magnetic flux vector follows ^* . Such a second control mode is suitable for ensuring high response to torque.

  In addition, the present embodiment also has an advantage that both the first control mode and the second control mode can be realized without using a speed sensor and a position sensor.

(Embodiment 2)
Hereinafter, the rotating machine control apparatus 200a of Embodiment 2 will be described. In the second embodiment, the same parts as those in the first embodiment are denoted by the same reference numerals, and description thereof may be omitted.

  As illustrated in FIG. 7, the rotating machine control unit 201a of the second embodiment includes a movement amount specifying unit 211a.

(Movement amount specifying unit 211a)
The movement amount specifying unit 211a obtains the second movement amount (movement amount of the primary magnetic flux vector) Δθ _s from the reference torque T _ref , the estimated torque _Te and the command speed ω _ref ^* . As shown in FIG. 8, the movement amount specifying unit 211a includes a low-pass filter (LPF) 252, a changeover switch 251, a torque subtracting unit 250, a PI compensator 145, a multiplying unit 146, and an adding unit 147. Have.

In the movement amount specifying unit 211a, the first control mode and the second control mode can be switched by switching the changeover switch 251. Specifically, the movement amount specifying unit 211a can switch the control mode according to FIG. In the second control mode, the rotating machine control device 102 causes the torque of the three-phase rotating machine 102 to follow the command torque _Te ^* .

In the first control mode, LPF252 extracts the low frequency component T ₁ of the estimated torque T _e (specific). Specifically, the LPF 252 obtains the low frequency component T ₁ according to the equation (1-21). In Expression (1-21), ω _c is a cutoff angular frequency.

Next, in the first control mode, the changeover switch 251 selects the low frequency component T ₁ as the command torque _Te ^* . Next, the torque subtracting unit 250, by subtracting the command torque T _e ^* estimated torque T _e (low frequency component T _1), to identify the torque deviation ^{_{ΔT (= T e * -T e}} ). This torque deviation ΔT has the same meaning as the vibration component ΔT _{1 of the} first embodiment. Therefore, this torque deviation ΔT can be referred to as a vibration component.

In the first control mode, thereafter, the PI compensator 145 specifies the first movement amount Δθ based on Expression (1-13C). The multiplication unit 146 identifies the product ω _ref ^* T _s by multiplying the command speed ω _ref ^* by the control period T _s . The adding unit 147 adds the first movement amount Δθ and the product ω _ref ^* T _s . As a result, the second movement amount (movement amount of the primary magnetic flux vector) Δθ _s is obtained.

Thus, in a first control mode, the movement amount determination section 211a includes a low-frequency component T _1, which is a frequency component lower than the cutoff angular frequency omega _c in the estimated torque T _e, the low-frequency components T ₁ and the estimated torque T _A first movement amount Δθ that makes the first difference, which is a difference from _e , close to zero is specified. Then, the second movement amount Δθ _s is specified by summing the first movement amount Δθ and the product ω _ref ^* T _s .

In the second control mode, the changeover switch 251 selects the reference torque T _ref as the command torque T _e ^* . Torque subtraction section 250, by subtracting the command torque T _e ^* (see torque T _ref) from the estimated torque T _e, identifies the torque deviation ^{_{ΔT (= T e * -T e}} ). The PI compensator 145 specifies the first movement amount Δθ based on the formula (1-13C). The multiplication unit 146 identifies the product ω _ref ^* T _s by multiplying the command speed ω _ref ^* by the control period T _s . The adding unit 147 adds the first movement amount Δθ and the product ω _ref ^* T _s . As a result, the second movement amount (movement amount of the primary magnetic flux vector) Δθ _s is obtained.

In both the first control mode and the second control mode, the command torque T _e ^* is given to the command amplitude specifying unit 122. The command amplitude specifying unit 122 specifies the command amplitude | ψ _s ^* | from the command torque T _e ^* .

(Effect of this embodiment)
In the first control mode of the second embodiment, as in the first control mode of the first embodiment, the reference torque T _ref is not used to specify the second movement amount Δθ _s . Therefore, the first control mode of the second embodiment is also advantageous for ensuring stability when the three-phase rotating machine 102 is driven at a low speed. Furthermore, in the first control mode of the second embodiment, the output of the low-pass filter (LPF) 252 is used as the command torque T _e ^*, the command torque T _e ^* is the command phase theta _s ^* and instruction amplitude | ψ _s ^* | It is reflected in. Thereby, a stable command magnetic flux vector ψ _s ^* is generated, and the primary magnetic flux vector follows the stable command magnetic flux vector ψ _s ^* . Due to the stability obtained by the first control mode, torque fluctuation at the time of switching between the first control mode and the second control mode is alleviated. In addition, the second control mode of the second embodiment is advantageous in securing high responsiveness to torque, as in the second control mode of the first embodiment.

  According to the present embodiment, it is possible to switch between the first control mode and the second control mode only by changing the operation of the movement amount specifying unit 211a. Actually, in the present embodiment, in the first control mode and the second control mode, the elements other than the movement amount specifying unit 211a in the rotating machine control device 100 operate in the same manner (this also applies to the third embodiment). Is). That is, the commonality of the control modes in both control modes can be increased. That is, according to the present embodiment, it is easy to avoid the control becoming unstable when the control mode is switched or the physical quantity of the three-phase rotating machine 102 greatly vibrating. Torque fluctuations during control mode switching are also easily suppressed.

  In addition, as described above, switching between the two control modes can be performed only by changing the operation of the movement amount specifying unit 211a, that is, many operations are common in both control modes, such as simplification of the control system and memory saving. It is advantageous from the viewpoint.

(Embodiment 3)
Hereinafter, the rotating machine control apparatus 200b of Embodiment 3 will be described. In the third embodiment, the same parts as those in the second embodiment are denoted by the same reference numerals, and the description thereof may be omitted.

  As illustrated in FIG. 9, the rotating machine control unit 201b according to the third embodiment includes a movement amount specifying unit 211b.

(Movement amount specifying unit 211b)
The movement amount specifying unit 211b obtains the second movement amount (movement amount of the primary magnetic flux vector) Δθ _s from the reference torque T _ref , the estimated torque _Te and the command speed ω _ref ^* . As illustrated in FIG. 10, the movement amount specifying unit 211b includes a low-pass filter (LPF) 252, a changeover switch 251, a limiter (torque limiting unit) 253, a torque subtracting unit 250, a PI compensator 145, and a multiplying unit. 146 and an adder 147.

In the movement amount specifying unit 211b, the first control mode and the second control mode can be switched by switching the changeover switch 251. Specifically, the movement amount specifying unit 211b can switch the control mode according to FIG. In the second control mode, the rotating machine control device 102 causes the torque of the three-phase rotating machine 102 to follow the command torque _Te ^* .

In the first control mode, LPF252 extracts the low frequency component T ₁ of the estimated torque T _e (specific). Specifically, the LPF 252 obtains the low frequency component T ₁ according to the equation (1-21). The changeover switch 251 selects the low frequency component T ₁ .

In the first control mode, the limiter 253, to identify the command torque T _e ^* from the low-frequency component T _1. Specifically, the limiter 253, in accordance with equation (1-22A), obtains the command torque T _e ^*. In the example of Expression (1-22A), the absolute value of the upper limit value T _{lim and} the absolute value of the lower limit value −T _lim are the same, but they may not be the same. This also applies to the formula (1-22B).

In the first control mode, then the torque subtraction unit 250, by subtracting the estimated torque T _e from the output of the limiter 253, to identify the torque deviation [Delta] T. The PI compensator 145 specifies the first movement amount Δθ based on the formula (1-13C). The multiplication unit 146 identifies the product ω _ref ^* T _s by multiplying the command speed ω _ref ^* by the control period T _s . The adding unit 147 adds the first movement amount Δθ and the product ω _ref ^* T _s . As a result, the second movement amount (movement amount of the primary magnetic flux vector) Δθ _s is obtained.

The control PI compensator 145 performs the first control mode, and output the difference between the estimated torque T _e of the limiter 253 is close to zero (specifically, converges to zero). In this way, as a result, (converges to zero in particular) vibration component of the estimated torque T _e also approaches zero.

In the second control mode, the changeover switch 251 selects the reference torque _Tref .

In the second control mode, the limiter 253 specifies the command torque _Te ^* from the reference torque _Tref . Specifically, the limiter 253, in accordance with equation (1-22B), obtains the command torque T _e ^*.

In the second control mode, then the torque subtraction unit 250, by subtracting the estimated torque T _e from the output of the limiter 253, to identify the torque deviation [Delta] T. The PI compensator 145 specifies the first movement amount Δθ based on the formula (1-13C). The multiplication unit 146 identifies the product ω _ref ^* T _s by multiplying the command speed ω _ref ^* by the control period T _s . The adding unit 147 adds the first movement amount Δθ and the product ω _ref ^* T _s . As a result, the second movement amount (movement amount of the primary magnetic flux vector) Δθ _s is obtained.

In both the first control mode and the second control mode, the command torque T _e ^* is given to the command amplitude specifying unit 122. The command amplitude specifying unit 122 specifies the command amplitude | ψ _s ^* | from the command torque T _e ^* .

(Effect of this embodiment)
In the first control mode of the third embodiment, when the low frequency component T ₁ is equal to or higher than the upper limit value T _lim or lower than the lower limit value −T _lim , the upper limit value T _lim or the lower limit value −T _lim is set as the command torque. Used as _Te ^* . In the second control mode of the third embodiment, when the reference torque T _ref is or not more than the upper limit T _lim Exceeded or lower limit -T _lim, it commands the upper limit T _lim or the lower limit value -T _lim torque T _Used as _e ^* . That is, in both control modes, the command torque _Te ^* does not become an extremely small value or an extremely large value. The command torque T _e ^* is reflected in the command phase θ _s ^* and the command amplitude | ψ _s ^* |. Thereby, a stable command magnetic flux vector ψ _s ^* is generated, and the primary magnetic flux vector follows the stable command magnetic flux vector ψ _s ^* . Therefore, according to the limiter 253, torque fluctuation is suppressed even during a transition during switching of the control mode.

  Further, according to the limiter 253, a situation in which the current flowing through the three-phase rotating machine 102 becomes excessive can be avoided. That is, abnormal heat generation in the three-phase rotating machine 102, the inverter 104, and the like can be avoided. In this respect, it can be said that the limiter 253 contributes to the realization of a highly reliable rotating machine control device.

[Derivation of Formula (1-9B)]
Hereinafter, derivation of the formula (1-9B) will be described. The mathematical model in the general coordinate system of the induction machine (more specifically, the γδ general coordinate system rotating at an arbitrary speed ω _r ) is a well-known document (Shinji Shinnaka: “Minimum Dimension D Factor Associated with Instantaneous Speed Estimation” Sensorless vector control of induction motor using magnetic flux state observer ", IEEJ Transactions D, Vol.135, No.3, pp.299-307, (2015)), equations (2-1), (2-2 ), (2-3), and ψ _2nd = M _n i _d , ψ _2nq = 0, the equations (2-5), (2-6) and (2-7) in the dq coordinate system It can be expressed as follows. Moreover, the relationship of Formula (2-4A) and Formula (2-4B) is established. M is mutual inductance, L ₁ is stator inductance, L ₂ is rotor inductance, _Ra is stator resistance, R ₂ is rotor resistance, M _n is normalized mutual inductance, R _2n is normalized rotor resistance, l _1t is a stator total leakage inductance, W ₂ is a rotor reverse time constant (reciprocal of the rotor time constant), ψ ₂ is a rotor magnetic flux (secondary magnetic flux), ψ _2n is a normalized rotor magnetic flux (normalized two Secondary magnetic flux), v is the stator voltage, i is the stator current, ω ₁ is the stator magnetic flux rotational speed, ω _2n is the rotor speed, N _p is the number of pole pairs, T is the torque, I is the 2 × 2 unit matrix, J is a 2 × 2 alternating matrix, D (s, ω _r ) is a D factor, and s is a differential operator d / dt.

(Relationship between primary magnetic flux and normalized secondary magnetic flux)
In the steady state, an expression (2-9) relating to the primary magnetic flux and an expression (2-10) relating to the normalized secondary magnetic flux are derived based on the expression (2-5). The relationship of Formula (2-11) is established between the primary magnetic flux and the normalized secondary magnetic flux. This relationship is shown in the vector diagram of FIG. ψ _s is a stator magnetic flux (primary magnetic flux).

From equation (2-11) and 11, it can be seen that consists of a rotor flux [psi _s virtual armature reaction flux normalized rotor flux ψ _2n l _1t i _a. By transforming equation (2-11), equation (1-9B) is derived.

[Example of calculation formula to obtain command amplitude | ψ _s ^* |]
Hereinafter, an example of a calculation formula for obtaining the command amplitude | ψ _s ^* | without using the command amplitude specifying unit 122 will be described with reference to FIGS. 12 and 13.

In this example, the command amplitude | ψ _s ^* | is calculated by the temporary setting unit 330, the amplitude correction amount generation unit 317, and the addition unit 331 (see FIG. 12). In this calculation, the command amplitude | ψ _s ^* | is calculated from the axial currents i _α and i _β and the estimated magnetic flux ψ _s (estimated magnetic flux ψ _α , ψ _β ).

(Temporary setting unit 330)
The temporary setting unit 330 sets (specifies) the temporary amplitude | ψ _ref | of the command magnetic flux vector ψ _s ^* . In this example, the temporary amplitude | ψ _ref | is stored in the temporary setting unit 330 in advance. The provisional amplitude | ψ _ref | is a constant. For example, the temporary amplitude | ψ _ref | can be used as the magnetic flux parameter ψ _a .

(Amplitude correction amount generation unit 317)
The amplitude correction amount generation unit 317 specifies the amplitude correction amount Δψ from the axial currents i _α and i _β and the estimated magnetic flux ψ _s (estimated magnetic flux ψ _α , ψ _β ). As illustrated in FIG. 13, the amplitude correction amount generation unit 317 includes an error parameter calculation unit 321, an error parameter deviation calculation unit 322, and a PI compensation unit 323.

The amplitude correction amount generation unit 317 performs the same operation regardless of whether the d-axis inductance L _d and the q-axis inductance L _q are different from each other. Specifically, when there is an inductance difference, a value between the d-axis inductance and the q-axis inductance can be used as the inductance L. Further, if the magnetic saliency is not large, there is no harm in handling the L = L _d. That is, as the inductance value, a d-axis inductance value, a value larger than the d-axis inductance and smaller than the q-axis inductance, or a value smaller than the d-axis inductance and larger than the q-axis inductance can be used.

The specification of Japanese Patent No. 4972135 is helpful in setting the inductance L as described above. Japanese Patent No. 4972135 describes a technique related to a dm-qm coordinate system. The dm-qm coordinate system makes it possible to treat a motor having magnetic saliency such as a permanent magnet synchronous motor having an embedded magnet structure in the same manner as a permanent magnet synchronous motor having no magnetic saliency. Maximum torque control (maximum torque / current control) can be performed by using the dm-qm coordinate system and setting the dm-axis current (γ-axis current in the control coordinate system) to zero. When the three-phase rotating machine 102 has magnetic saliency, the d-axis current can be replaced with the dm-axis current, the magnetic flux ψ _a can be replaced with the extended flux linkage vector Φ _exm , and the inductance L can be replaced with the virtual inductance L _m. it can. For details of the dm-axis current, the extended flux linkage vector Φ _exm and the virtual inductance L _m , refer to Japanese Patent No. 4972135 (Formula 36 and paragraphs 0182 to 0183). Note that L _m satisfies L _d ≦ L _m <L _q . When there is no inductance difference, the dm-qm coordinate system and the general dq coordinate system coincide with each other, and Lm = Ld = Lq may be set. That is, the idea about the case where there is an inductance difference includes the idea about the case where there is no inductance difference.

(Error parameter calculation unit 321)
The error parameter calculation unit 321 calculates the error parameter ε from the virtual inductance (inductance of the three-phase rotating machine 102) L _m , the shaft currents i _α , i _β, and the estimated magnetic flux ψ _s (estimated magnetic flux ψ _α , ψ _β ). To do. Specifically, first, estimate the armature reaction magnetic flux (obtain the estimated armature reaction flux L _m i _a). The alpha-axis component and beta-axis component of the estimated armature reaction flux L _m i _a, respectively estimated armature reaction flux L _m i _α, referred to as estimated armature reaction flux L _m i _β. The estimated armature reaction magnetic flux L _m i _α and the estimated armature reaction magnetic flux L _m i _β are the products of the virtual inductance L _m and the axial currents i _α and i _β . Next, the magnet magnetic flux is estimated from the estimated magnetic flux ψ _s (estimated magnetic flux ψ _α , ψ _β ) and the estimated armature reaction magnetic flux L _m i _a (estimated armature reaction magnetic flux L _m i _α , L _m i _β ) ( Estimated magnet magnetic flux ψ ′ _ae is obtained). The α-axis component and β-axis component of the estimated magnet magnetic flux ψ ′ _ae are described as estimated magnet magnetic flux ψ ′ _aeα and ψ ′ _aeβ , respectively. Specifically, as shown in the equations (3-1) and (3-2), the estimated magnet is obtained by subtracting the estimated armature reaction magnetic fluxes L _m i _α and L _m i _β from the estimated magnetic fluxes ψ _α and ψ _β. The magnetic fluxes ψ ′ _aeα and ψ ′ _aeβ are obtained. Next, the error parameter ε is calculated from the estimated magnet magnetic fluxes ψ ′ _aeα and ψ ′ _aeβ and the shaft currents i _α and i _β as shown in the equation (3-3).

(Error parameter deviation calculation unit 322)
The error parameter deviation calculation unit 322 acquires the command error parameter ε ^* and the error parameter ε, and obtains the deviation (error parameter deviation Δε: ε ^* −ε). As the error parameter deviation calculation unit 322, a known operator can be used. The command error parameter ε ^* can be an arbitrary value. In this example, the amplitude correction amount generation unit 317 is configured for MTPA. In order to establish MTPA, it is necessary to make the estimated magnetic flux ψ ′ _ae orthogonal to the axial currents i _α and i _β . Therefore, in this example, the command error parameter ε ^* is set to zero in order to make the inner product of the estimated magnetic flux ψ ′ _ae and the shaft currents i _α and i _β zero.

(PI compensation unit 323)
The PI compensation unit 323 obtains the error parameter deviation Δε and specifies the amplitude correction amount Δψ so that it becomes zero. Specifically, as shown in Expression (3-4), the amplitude correction amount Δψ is obtained by performing a proportional / integral calculation using the error parameter deviation Δε as an input. As described above, in this example, the error parameter deviation calculation unit 322 generates an error parameter deviation Δε for MTPA. Therefore, the PI compensation unit 323 generates an amplitude correction amount Δψ that is suitable for MTPA.

(Adder 331)
The adder 331 specifies the command amplitude | ψ _s ^* | from the temporary amplitude | ψ _ref | and the amplitude correction amount Δψ. The command amplitude | ψ _s ^* | is the sum of the temporary amplitude | ψ _ref | and the amplitude correction amount Δψ. In this way, MTPA can be performed.

As described above, the rotating machine control devices (100, 200a, 200b) according to the first to third embodiments are arranged so that the primary magnetic flux vector of the three-phase rotating machine (102) follows the command magnetic flux vector ψ _s ^*. A voltage vector is applied to the three-phase rotating machine using (104). The rotating machine control device can switch between a second control mode in which the torque of the three-phase rotating machine follows the command torque _Te ^* and a first control mode different from the second control mode. The rotating machine control device includes a torque estimation unit (109), a phase estimation unit (included in the speed / phase estimation unit 110), a movement amount identification unit (111, 211a, 211b), and a command phase identification unit ( 127) and a command magnetic flux specifying unit (112). Torque estimating unit includes a primary flux vector, using a current vector of a three-phase rotary machine, (which identifies the estimated torque T _e) estimates the torque of the three-phase rotary machine. The phase estimation unit estimates the phase of the primary magnetic flux vector (identifies the estimated phase θ _s ). Movement amount determination section, the product omega _ref ^* T _s command speed omega _ref ^* to the period T _s of the control cycle of the 3-phase rotating machine is calculated, the zero vibration component estimated torque T _e in the first control mode In the second control mode, the first movement amount Δθ that specifies the difference between the command torque T _e ^* and the estimated torque to be close to zero is specified, and the product ω _ref ^* T _s and the first movement amount are specified. By adding Δθ, the second movement amount Δθ _s to which the phase of the primary magnetic flux vector should move in one control cycle is specified. The command phase specifying unit uses the estimated phase θ _s and the second movement amount Δθ _s to specify the command phase θ _s ^* that is the phase of the command magnetic flux vector ψ _s ^* . The command magnetic flux specifying unit specifies the command magnetic flux vector ψ _s ^* using the command phase θ _s ^* . This rotating machine control device can secure a high response to torque when the rotation speed is high, and a control mode (first control mode) that can suppress a decrease in control performance when the rotation speed of the three-phase rotating machine is low. Can be switched between different control modes (second control mode). In addition, this rotating machine control device can suppress torque fluctuations during control mode switching.

In Embodiment 1, in a first control mode, the movement amount determination unit identifies the first movement amount Δθ to approximate the high-frequency component is a frequency component higher than the cutoff angular frequency omega _c in the estimated torque T _e to zero. Thus, the vibration component of the estimated torque T _e can be easily brought close to zero.

In the first embodiment, in the first control mode, the first movement amount Δθ is specified by feedback control that brings the high-frequency component closer to zero. In the second control mode, the first movement amount Δθ is identified by a feedback control closer to zero the difference between the command torque T _e ^* and the estimated torque T _e. Thus, in a first control mode, the vibration component of the estimated torque T _e can be easily brought close to zero. In the second control mode, the difference between the command torque T _e ^* and the estimated torque T _e can be brought close to easily zero.

The rotating machine control device (100) according to the modification of the first embodiment includes a command amplitude specifying unit (122). In both the first control mode and the second control mode, (i) the same fixed value is used as the command amplitude | ψ _s ^* |, which is the amplitude of the command magnetic flux vector ψ _s ^* , or (ii) the same calculation formula is used. The value obtained in this way is used as the command amplitude | ψ _s ^* | which is the amplitude of the command magnetic flux vector ψ _s ^* . In both the first control mode and the second control mode, the command magnetic flux specifying unit specifies the command magnetic flux vector ψ _s ^* using the command amplitude | ψ _s ^* |. This is advantageous from the viewpoint of suppressing torque fluctuation at the time of control mode switching.

In Embodiment 2, in the first control mode, the movement amount determination section, the difference between the low frequency component which is a frequency component lower than the cutoff angular frequency omega _c in the estimated torque T _e, and the estimated torque T _e and the low-frequency component The first movement amount Δθ that makes the first difference (torque deviation ΔT) close to zero is specified. Thus, the vibration component of the estimated torque T _e can be easily brought close to zero.

The rotating machine control device (201a) according to the second embodiment includes a reference torque specifying unit (121) and a command amplitude specifying unit (122). The reference torque specifying unit specifies the reference torque T _ref that the torque of the three-phase rotating machine should follow when the rotor speed of the three-phase rotating machine (102) is made to follow the command speed ω _ref ^* . In the first control mode, the low frequency component is used as the command torque _Te ^* . In the second control mode, the reference torque T _ref is used as the command torque T _e ^* . In both the first and second control modes, the first movement amount Δθ is identified by a feedback control closer to zero the difference between the command torque T _e ^* and the estimated torque T _e. In both the first and second control modes, instruction amplitude specifying unit instruction amplitude is commanded flux vector [psi _s ^* of amplitude using command torque T _e ^* | ^ψ _s ^* | identifies the command flux particular The unit specifies the command magnetic flux vector ψ _s ^* using the command amplitude | ψ _s ^* |. Thus, in a first control mode, the vibration component of the estimated torque T _e can be easily brought close to zero. In the second control mode, the difference between the command torque T _e ^* and the estimated torque T _e can be brought close to easily zero. Further, this is advantageous from the viewpoint of suppressing torque fluctuation at the time of control mode switching. In this way, it is easy to specify the command amplitude in accordance with the control purpose (maximum torque / current, etc.) in both the first control mode and the second control mode.

The movement amount specifying unit (211b) according to the third embodiment includes a limiter (253). The limiter outputs an upper limit value when the input to the limiter is greater than or equal to the upper limit value, outputs a lower limit value when the input to the limiter is less than or equal to the lower limit value, and the input to the limiter is higher than the lower limit value. When the value is smaller than the value, the input to the limiter is output. In the first control mode, the movement amount determination section, a low-frequency component is a frequency component lower than the cutoff angular frequency omega _c in the estimated torque T _e is inputted to the limiter, the difference of the output of the limiter and the estimated torque T _e A first movement amount Δθ that makes a certain second difference (torque deviation ΔT) close to zero is specified. In this way, the estimated vibration component of the torque can be brought close to zero. Further, it is possible to avoid a situation in which the current flowing through the three-phase rotating machine is excessive, and it is possible to realize a highly reliable rotating machine control device.

The rotating machine control device (201b) according to the third embodiment includes a reference torque specifying unit (121) and a command amplitude specifying unit (122). The reference torque specifying unit specifies the reference torque T _ref that the torque of the three-phase rotating machine should follow when the rotor speed of the three-phase rotating machine (102) is made to follow the command speed ω _ref ^* . In the second control mode, the reference torque T _ref is input to the limiter (253). In both the first and second control modes, the output of the limiter is used as the command torque T _e ^*, the first moving amount by the feedback control to bring the difference between the command torque T _e ^* and the estimated torque T _e to zero Δθ is specified. In both the first and second control modes, instruction amplitude specifying unit instruction amplitude which is a command flux vector [psi _s ^* of amplitude using command torque T _e ^* | ^ψ _s ^* | identifies the command flux particular The unit specifies the command magnetic flux vector ψ _s ^* using the command amplitude | ψ _s ^* |. Thus, in a first control mode, the vibration component of the estimated torque T _e can be easily brought close to zero. Further, it is possible to close to zero a difference between the command torque T _e ^* and the estimated torque T _e in the second control mode. Further, this is advantageous from the viewpoint of suppressing torque fluctuation at the time of control mode switching.

  The technology according to the present disclosure can be applied to a three-phase rotating machine such as a cage induction machine or a synchronous machine. The three-phase rotating machine to which the technology according to the present disclosure is applied is suitable for a heat pump type refrigeration apparatus used in an air conditioner or a hot water heater. The technology according to the present disclosure is suitable for a fan and blower control device.

100, 200a, 200b Rotating machine control devices 101, 201a, 201b Rotating machine control unit 102 Three-phase rotating machine 103 Duty generation unit 104 PWM inverter 105a First current sensor 105b Second current sensor 106 u, w / α, β conversion unit 107 Command voltage specifying unit 108 Magnetic flux estimating unit 109 Torque estimating unit 110 Speed / phase estimating unit 111, 211a, 211b Movement amount specifying unit 112 Command magnetic flux specifying unit 113a α-axis magnetic flux deviation specifying unit 113b β-axis magnetic flux deviation specifying unit 114 α, β / u, v, w conversion unit 116 Base driver 117 Smoothing capacitor 118 DC power supply 119a to 119f Switching element 120a to 120f Freewheeling diode 121 Reference torque specifying unit 122 Command amplitude specifying unit 127 Command phase specifying unit 141, 250 Torque subtracting unit 142 High pass filter HPF)
143, 146 Multiplier 144, 251 Changeover switch 145 PI compensator 147 Adder 252 Low-pass filter (LPF)
253 Limiter 317 Amplitude correction amount generator 321 Error parameter calculator 322 Error parameter deviation calculator 323 PI compensation unit 330 Temporary setting unit 331 Adder

Claims (9)

A rotating machine control device that applies a voltage vector to the three-phase rotating machine using an inverter so that a primary magnetic flux vector of the three-phase rotating machine follows the command magnetic flux vector,
The rotating machine control device can switch between a second control mode for causing the torque of the three-phase rotating machine to follow a command torque, and a first control mode different from the second control mode,
The rotating machine control device includes:
A torque estimator that estimates the torque of the three-phase rotating machine using the primary magnetic flux vector and the current vector of the three-phase rotating machine;
A phase estimator for estimating the phase of the primary magnetic flux vector;
The product of the command speed of the three-phase rotating machine and the cycle of the control cycle is calculated, and the estimated vibration component of the torque is approximated to zero in the first control mode, and the command in the second control mode. By identifying a first movement amount that approximates the difference between the torque and the estimated torque to zero, and summing the product and the first movement amount, the phase of the primary magnetic flux vector is determined in one control cycle. A movement amount specifying unit for specifying the second movement amount to be moved;
A command phase specifying unit that specifies a command phase that is a phase of the command magnetic flux vector using the estimated phase and the second movement amount;
A rotating machine control device comprising: a command magnetic flux specifying unit that specifies the command magnetic flux vector using the command phase.   The said movement amount specific | specification part specifies the said 1st movement amount which brings the high frequency component which is a frequency component higher than the cutoff angular frequency in the estimated said torque close | similar to zero in the said 1st control mode. Rotating machine control device. In the first control mode, the first movement amount is specified by feedback control that brings the high-frequency component close to zero,
3. The rotating machine control device according to claim 2, wherein in the second control mode, the first movement amount is specified by feedback control that brings a difference between the command torque and the estimated torque close to zero. The rotating machine control device includes a command amplitude specifying unit,
In both the first control mode and the second control mode, (i) the same fixed value is used as the command amplitude which is the amplitude of the command magnetic flux vector, or (ii) the value obtained using the same calculation formula is Used as a command amplitude which is the amplitude of the command magnetic flux vector,
4. The rotating machine control device according to claim 2, wherein the command magnetic flux specifying unit specifies the command magnetic flux vector using the command amplitude in both the first control mode and the second control mode. 5.   In the first control mode, the movement amount specifying unit is a difference between a low-frequency component that is a frequency component lower than a cutoff angular frequency in the estimated torque and the torque estimated as the low-frequency component. The rotating machine control device according to claim 1, wherein the first movement amount that causes the first difference to approach zero is specified. The rotating machine control device includes a reference torque specifying unit and a command amplitude specifying unit,
The reference torque specifying unit specifies the reference torque that the torque of the three-phase rotating machine should follow when the rotor speed of the three-phase rotating machine follows the command speed,
In the first control mode, the low frequency component is used as the command torque,
In the second control mode, the reference torque is used as the command torque,
In both the first control mode and the second control mode, the first movement amount is specified by feedback control that brings the difference between the command torque and the estimated torque close to zero,
In both the first control mode and the second control mode, the command amplitude specifying unit uses the command torque to specify a command amplitude that is an amplitude of the command magnetic flux vector, and the command magnetic flux specifying unit includes the command amplitude. The rotating machine control device according to claim 5, wherein the command magnetic flux vector is specified by using. The movement amount specifying unit has a limiter,
The limiter outputs the upper limit value when the input to the limiter is greater than or equal to an upper limit value, and outputs the lower limit value when the input to the limiter is less than or equal to a lower limit value, and the input to the limiter is When the value is larger than the lower limit value and smaller than the upper limit value, the input to the limiter is output.
In the first control mode, the movement amount specifying unit causes the limiter to input a low frequency component that is a frequency component lower than the cutoff angular frequency in the estimated torque, and the torque estimated as the output of the limiter. 2. The rotating machine control device according to claim 1, wherein the first movement amount that causes the second difference, which is a difference between the first movement amount and the second difference to approach zero, is specified. The rotating machine control device includes a reference torque specifying unit and a command amplitude specifying unit,
The reference torque specifying unit specifies the reference torque that the torque of the three-phase rotating machine should follow when the rotor speed of the three-phase rotating machine follows the command speed,
In the second control mode, the reference torque is input to the limiter,
In both the first control mode and the second control mode, the output of the limiter is used as the command torque, and the first movement is performed by feedback control that brings the difference between the command torque and the estimated torque close to zero. The quantity is identified,
In both the first control mode and the second control mode, the command amplitude specifying unit uses the command torque to specify a command amplitude that is an amplitude of the command magnetic flux vector, and the command magnetic flux specifying unit includes the command amplitude. The rotating machine control device according to claim 7, wherein the command magnetic flux vector is specified using a command. A rotating machine control method for applying a voltage vector to the three-phase rotating machine using an inverter so that a primary magnetic flux vector of the three-phase rotating machine follows the command magnetic flux vector,
The rotating machine control method can switch between a second control mode in which the torque of the three-phase rotating machine follows the command torque and a first control mode different from the second control mode,
The rotating machine control method includes:
A torque estimation step of estimating a torque of the three-phase rotating machine using the primary magnetic flux vector and a current vector of the three-phase rotating machine;
A phase estimating step for estimating a phase of the primary magnetic flux vector;
The product of the command speed of the three-phase rotating machine and the cycle of the control cycle is calculated, and the estimated vibration component of the torque is approximated to zero in the first control mode, and the command in the second control mode. By identifying a first movement amount that approximates the difference between the torque and the estimated torque to zero, and summing the product and the first movement amount, the phase of the primary magnetic flux vector is determined in one control cycle. A movement amount specifying step for specifying a second movement amount to be moved;
A command phase specifying step of specifying a command phase that is a phase of the command magnetic flux vector using the estimated phase and the second movement amount;
And a command magnetic flux specifying step for specifying the command magnetic flux vector using the command phase.

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