JP2012257360A - Controller of rotary machine - Google Patents

Abstract

When a torque is estimated based on a torque formula “φ · id + P (Ld−Lq) · id · iq” or a map assuming a specific value as an armature flux linkage constant φ, the magnetic force of a permanent magnet of a motor generator is calculated. When an abnormality occurs in which the armature decreases, the armature flux linkage constant φ changes, so that the torque estimation accuracy is greatly reduced.
A diagnostic torque estimating unit calculates a diagnostic estimated torque Tde by dividing an effective electric power EP (= Vn · Ia · cosΔ) by an electrical angular velocity ω. Here, the norm Vn is the norm of the vector of the output voltage of the inverter, the norm Ia is the vector norm of the actual currents id and iq, and the phase difference Δ is the phase difference between the current vector and the voltage vector. The FB computation system abnormality diagnosis unit 60 diagnoses whether there is an abnormality in the computation system by comparing the estimated torque for control Te estimated by the method according to the above equation with the estimated torque for diagnosis Tde.
[Selection] Figure 2

Description

  The present invention includes a control estimation unit that receives a detected value of the current flowing through the rotary machine as input and estimates the torque of the rotary machine without using the electrical angular velocity information of the rotary machine, and is estimated by the control estimation unit. The present invention relates to a control device for a rotating machine that operates an output voltage of an AC voltage application circuit connected to the rotating machine in order to feedback control torque to a command value.

  As this type of control device, for example, as seen in Patent Document 1 below, based on the difference between the torque estimated based on the formula “φ · id + P (Ld−Lq) · id · iq” and the torque command value, Some have been proposed for diagnosing the presence or absence of abnormality in torque control. There are other torque estimation methods based on, for example, a map that assumes a specific value as the armature flux linkage number φ.

JP 2007-166821 A

  However, when the above formula or map is used, if there is an abnormality in which the magnetic force of the permanent magnet of the motor decreases, the armature linkage magnetic flux constant φ changes, so the torque estimation accuracy is greatly reduced.

  The present invention has been made in the process of solving the above-described problems, and its purpose is to estimate the torque of the rotating machine without using the detected value of the current flowing through the rotating machine as input and the electrical angular velocity information of the rotating machine. And a control device for a new rotating machine that operates an AC voltage application circuit connected to the rotating machine to feedback control the torque estimated by the control estimating means to a command value. There is.

  Hereinafter, means for solving the above-described problems and the operation and effect thereof will be described.

  The invention according to claim 1 further comprises control estimation means for receiving the detected value of the current flowing through the rotating machine and estimating the torque of the rotating machine regardless of the electrical angular velocity information of the rotating machine. In the control device for a rotating machine that operates the output voltage of an AC voltage application circuit connected to the rotating machine to feedback control the torque estimated by the command value to the command value, the operated output voltage, the current flowing through the rotating machine And a diagnostic estimation means for estimating the torque of the rotating machine based on a value obtained by dividing the power of the AC voltage application circuit by the electrical angular speed of the rotating machine, and the detected value of the rotating machine and the electrical angular speed of the rotating machine A diagnostic operator for diagnosing the presence or absence of abnormality of the feedback control based on a comparison between the torque estimated by the estimation means and the torque estimated by the control estimation means Characterized in that it comprises a and.

  In the above invention, the diagnosis estimating means and the control estimating means estimate the torque independently of each other. Here, when the estimated values by the torque estimating means are different, it is considered that an abnormality has occurred in the control estimating means used for the feedback control means, and consequently, an abnormality has occurred in the feedback control. In the above invention, in view of this point, it is possible to diagnose the presence or absence of abnormality in feedback control by providing a diagnostic means.

  In addition, it is desirable that the rotating machine includes a permanent magnet.

  In this case, the control diagnostic means is configured based on information about the armature flux linkage constant of the rotating machine. Therefore, when an abnormality occurs in which the magnetic flux of the permanent magnet decreases, an accurate torque cannot be estimated. On the other hand, the diagnostic estimation means estimates the torque independently of the armature flux linkage constant information of the rotating machine. For this reason, when there is a difference between the torques estimated by the pair of estimating means, it can be determined that the control diagnosing means cannot accurately estimate the torque due to a magnetic flux abnormality or the like.

  According to a second aspect of the present invention, in the first aspect of the present invention, the input parameter of the diagnostic estimation means includes a vector norm of a current flowing through the rotating machine, and a vector of the current and a vector of the output voltage to be operated. The effective power of the AC voltage application circuit obtained from the product of the vector norm of the current and the output voltage to be operated and the phase difference is divided by the electrical angular velocity of the rotating machine. The torque of the rotating machine is estimated based on.

  The invention according to claim 3 is the invention according to claim 2, wherein the vector norm of the current is calculated from a dq coordinate component.

  In the above invention, the current vector norm can be easily calculated by using the DC component.

  According to a fourth aspect of the present invention, in the invention according to any one of the first to third aspects, the diagnostic unit is configured to generate a torque based on a degree of deviation between the torque estimated by the diagnostic estimation unit and the command value. It further has a function of diagnosing the presence or absence of control abnormality.

  In the above invention, based on the difference between the torque estimated by the diagnostic estimation means and the command value, it is possible to diagnose whether the actual torque of the rotating machine is controlled according to the command value. Here, if the torque is not controlled according to the command value, it is an abnormality that the torque does not become the command value because the calculation system of the feedback control is not functioning normally, or an abnormality caused by other factors, etc. There are multiple factors. In this regard, in the above invention, when there is a difference between the torques estimated by the diagnostic estimation unit and the control estimation unit, the feedback control calculation system is not functioning normally, so that the torque becomes the command value. It can be identified as an anomaly that must not be.

The system block diagram concerning one Embodiment. The block diagram which shows the process of MGECU concerning the embodiment. The flowchart which shows the procedure of the calculation process of the diagnostic torque concerning the embodiment. The flowchart which shows the procedure of the abnormality diagnosis process concerning the embodiment.

  Hereinafter, an embodiment in which a control device for a rotating machine according to the present invention is applied to a control device for a rotating machine as an in-vehicle main machine will be described with reference to the drawings.

  FIG. 1 shows a system configuration diagram according to the present embodiment.

  As shown in the figure, the motor generator 10 is a three-phase electric motor / generator as an in-vehicle main machine, and is mechanically coupled to the drive wheels 14. Specifically, the rotating shaft 10a of the motor generator 10 is mechanically coupled to the drive wheels 14 via an electronically controlled clutch C1 and a transmission 12. In the present embodiment, an embedded magnet synchronous machine (IPMSM) is assumed as the motor generator 10.

  The rotating shaft 10a of the motor generator 10 is further mechanically coupled to an internal combustion engine (engine 16) via an electronically controlled clutch C2.

  The motor generator 10 is connected via an inverter INV to a high voltage battery 18 whose terminal voltage is a predetermined high voltage (for example, 100 V or more). On the other hand, the inverter INV includes three sets of series connection bodies of switching elements S * p, S * n (* = u, v, w), and the connection points of these series connection bodies are U, They are connected to the V and W phases, respectively. In the present embodiment, insulated gate bipolar transistors (IGBTs) are used as the switching elements S * p and S * n. In addition, diodes D * p and D * n are connected in antiparallel to these.

  In the present embodiment, the following is provided as detection means for detecting the state of the motor generator 10 and the inverter INV. First, a voltage sensor 20 that detects an input voltage (power supply voltage VDC) of the inverter INV is provided. Further, current sensors 22 and 24 for detecting currents iv and iw flowing through the V-phase and W-phase of motor generator 10 are provided. Furthermore, a rotation angle sensor 26 such as a resolver for detecting the rotation angle θ (electrical angle) of the motor generator 10 is provided.

  The detection values of the various sensors are taken into the motor generator electronic control unit (MGECU 30) constituting the low-pressure system via an interface (not shown). The MGECU 30 exchanges data with a hybrid electronic control device (HVECU 32), which is a higher-level control device, by CAN communication or the like. In particular, MGECU 30 controls the torque of motor generator 10 based on torque basic command value Tr 0 notified from HVECU 32. This is executed by generating and outputting an operation signal for operating the inverter INV based on the detection values of the various sensors. Here, signals for operating the switching elements S * p and S * n of the inverter INV are the operation signals g * p and g * n.

  FIG. 2 shows a block diagram of processing relating to generation of the operation signal of the inverter INV.

  In the two-phase conversion unit 40, the currents iv and iw detected by the current sensors 22 and 24 are converted into actual currents id and iq in the dq coordinate system. The phase / amplitude calculator 42 calculates the vector norm (amplitude) of the actual currents id and iq and the phase of the vector. Here, the norm of the vector is defined by the square root of the sum of the squares of the components of the vector. Based on the amplitude and phase of the actual currents id and iq calculated by the amplitude / phase calculation unit 42, the control torque estimation unit 46 performs a map calculation of the estimated torque value (control estimated torque Te). For example, this map is based on the following formula (c1), and if a value considering that the d-axis inductance Ld and the q-axis inductance Lq change according to the current is calculated: Good.

Te = φ · id + P (Ld−Lq) · id · iq (c1)
However, instead of this, a map created by obtaining the relationship between current and torque by experiments or the like may be used.

  The deviation calculating unit 48 calculates the difference between the torque command value Tr based on the basic command value Tr0 output from the HVECU 32 and the control estimated torque Te. Then, the phase setting unit 50 calculates the phase δ as an operation amount for performing feedback control of the control estimated torque Te to the torque command value Tr. This phase δ is calculated as the sum of the outputs of the proportional element and the integral element, which receives the difference between the control estimated torque Te and the torque command value Tr.

  The norm setting unit 52 uses a map storing the relationship between the torque command value Tr and the electrical angular velocity ω and the norm Vn of the output voltage vector of the inverter INV, and sets the norm Vn with the torque command value Tr and the electrical angular velocity ω as inputs. .

  Then, the operation signal generation unit 54 operates the operation signal g * p based on the phase δ set by the phase setting unit 50, the norm Vn output by the norm setting unit 52, the power supply voltage VDC, and the rotation angle θ. , G * n. Specifically, the operation signal generation unit 54 stores an operation signal waveform for one rotation period of the electrical angle as map data for each modulation factor. However, in view of the symmetry of the operation signal waveform, map data for “1/4” period may be stored, and the operation signal waveform for one rotation period may be calculated based on the symmetry.

  The operation signal generator 54 calculates a modulation rate based on the power supply voltage VDC and the norm Vn, and selects a corresponding operation signal waveform according to the calculated modulation rate. Here, the upper limit of the modulation rate is set to “1.27”, which is the modulation rate during rectangular wave control. For this reason, when the modulation rate is the maximum value “1.27”, the switching element S * p on the high potential side is turned on as one operation signal waveform in one rotation period of the electrical angle that is the waveform at the time of the rectangular wave control. A waveform (one pulse waveform) is selected in which a pair of periods of a period in which the switching element S * n on the low potential side is on and a period in which the low potential side switching element S * n is in an on state are each set.

  When the operation signal waveform is selected in this way, the operation signal generation unit 54 generates an operation signal by setting the output timing of this waveform based on the phase δ set by the phase setting unit 50.

  Next, a diagnosis process for the presence / absence of abnormality during the control of the motor generator 10 will be described. In the present embodiment, when diagnosing an abnormality as to whether or not the torque of the motor generator 10 is not normal, the correct torque (diagnostic estimated torque Tde) of the motor generator 10 is calculated by the diagnostic torque estimating unit 56. The torque abnormality diagnosis unit 58 diagnoses whether the torque of the motor generator 10 is normal based on the comparison between the torque command value Tr and the estimated diagnosis torque Tde. On the other hand, the FB calculation system abnormality diagnosis unit 60 diagnoses whether there is an abnormality in the feedback control calculation system based on a comparison between the control estimated torque Te and the diagnosis estimated torque Tde.

  Here, in consideration of the relationship of “torque × electrical angular velocity ω = power”, the diagnostic torque estimating unit 56 estimates the torque by dividing the electric power output from the inverter INV by the electric angular velocity ω. For this reason, even if the magnetic flux of the permanent magnet of the motor generator 10 changes, the torque estimation accuracy is not affected. In this sense, the diagnosis torque estimation unit 56 can estimate a torque with higher accuracy than the control estimation torque Te calculated by the control torque estimation unit 46.

  When the estimated torque Tde for diagnosis and the torque command value Tr deviate greatly, it can be determined that there is an abnormality in which the torque of the motor generator 10 is not controlled as the torque command value Tr.

  On the other hand, if the estimated torque Tde for diagnosis and the estimated torque Te for control are greatly deviated, an abnormality has occurred in the calculation system for feedback control, such as an abnormality in the estimated torque for control Te as the feedback control amount. Can be determined. Incidentally, this abnormality is an abnormality that prevents the control torque estimation unit 46 from estimating the correct torque due to, for example, an abnormality in which the magnetic flux of the permanent magnet decreases. At this time, a difference also occurs between the estimated diagnosis torque Tde and the torque command value Tr. However, since the difference between the estimated torque for diagnosis Tde and the torque command value Tr occurs, the cause of the abnormality cannot be narrowed down. This is because the cause of this abnormality is not limited to a decrease in the magnetic flux of the permanent magnet. Thus, by providing the FB calculation system abnormality diagnosis unit 60 and the torque abnormality diagnosis unit 58, there is an advantage that it becomes easy to specify the cause of the abnormality.

  Incidentally, the reason why the estimated torque for diagnosis Tde is not adopted as the feedback control amount is that the calculation load becomes large. That is, for calculating the estimated torque for diagnosis Tde, it is desirable to calculate the electrical angular velocity ω that varies at a time interval shorter than one electrical angle cycle, but when the calculation process of the electrical angular velocity ω that varies at a short time interval is performed. , The computation load increases. This is because the detection value of the rotation angle sensor 26 has an error depending on the electrical angle. In order to accurately calculate the electrical angular velocity ω that fluctuates in a short time interval, the error is corrected after correcting this error. This is because it is necessary to calculate the rate of change.

  FIG. 3 shows the procedure of the process for calculating the diagnostic estimated torque Tde according to this embodiment. This process is repeatedly executed in the MGECU 30 at a predetermined cycle, for example.

  In this series of processes, first, in step S10, the actual currents id and iq and the rotation angle θ are acquired. In the subsequent step S12, the norm Vn set by the norm setting unit 52 of FIG. 2 is acquired. In the subsequent step S14, the electrical angular velocity ω is calculated. In subsequent step S16, the phase difference Δ between the vector of the actual currents id and iq and the command voltage is calculated. Here, the phases of the actual currents id and iq may be calculated by, for example, “arctan {iq / (− id)}”. The phase of the command voltage may be the phase δ output from the phase setting unit 50. In the subsequent step S18, the effective power EP is calculated. This is “EP = Vn · Ia · cos Δ”. Here, the norm Ia of the current vector is used. In the subsequent step S20, the diagnostic estimated torque Tde is calculated by dividing the effective power EP by the electrical angular velocity ω. Here, the effective power EP is used because reactive power contributes to the torque among the power output to the motor generator 10, and the reactive power out of the power output to the motor generator 10. This is to exclude minutes.

  When the process of step S20 is completed, this series of processes is temporarily ended.

  FIG. 4 shows a diagnostic processing procedure according to the present embodiment. This process is repeatedly executed by the MGECU 30 at a predetermined cycle, for example.

  In this series of processes, first, in step S30, a basic torque command value Tr0 is received from the HVECU 32. In the subsequent step S32, the torque command value Tr is calculated by correcting the basic command value Tr0. This is based on the basic command value Tr0, the correction amount Tle for compensating the electric loss of the motor generator 10, the correction amount Tlm for compensating the mechanical loss of the motor generator 10, and the rotation of the motor generator 10 from the engine 16 side. This can be done by adding the correction amount Tb for compensating the periodic load torque applied to the shaft 10a.

  Here, the electrical loss of the motor generator 10 is copper loss, iron loss, or the like of the rotor or the stator. On the other hand, the mechanical loss of the motor generator 10 is a loss caused by mechanical factors such as friction between the rotating shaft 10a and its bearing portion. Further, the load torque is a force that prevents the rotation that occurs when the piston in the engine 16 repeatedly rises and falls as the crankshaft rotates. The load torque is generated only when the clutch C2 is engaged.

  The correction amount Tle for compensating for the electrical loss may be map-calculated according to, for example, the torque of the motor generator 10, the electrical angular velocity ω, and the power supply voltage VDC. Further, the correction amount Tlm for compensating the mechanical loss and the correction amount Tb for compensating the load torque may be subjected to map calculation according to the electrical angular velocity or the like.

  In the subsequent step S34, the norm Vn is calculated. This process is the process of the norm setting unit 52 shown in FIG. In the present embodiment, the cycle of the series of processes shown in this figure is set longer than the update cycle of the phase δ. In other words, the norm Vn update process is set longer than the update period of the phase δ. In the subsequent step S36, the control estimated torque Te and the diagnostic estimated torque Tde are acquired.

  In step S38, it is determined whether or not the absolute value of the difference between the diagnostic estimated torque Tde and the torque command value Tr is less than a specified value ΔT1. This process is for determining whether or not the actual torque of the motor generator 10 is controlled to the torque command value Tr. Here, the specified value ΔT1 is a value larger than the sum of the upper limit value of the difference between the actual torque and the torque command value Tr that can occur when the feedback control is normally performed and the estimation error of the diagnostic estimated torque Tde. Set to If a negative determination is made in step S38, it is determined in step S40 that there is an abnormality in which the actual torque of motor generator 10 deviates greatly from torque command value Tr.

  When an affirmative determination is made in step S38 or when the process of step S40 is completed, the process proceeds to step S42. In step S42, it is determined whether or not the absolute value of the difference between the estimated diagnosis torque Tde and the estimated control torque Te is less than a specified value ΔT2. This process is for determining whether there is an abnormality in the arithmetic system of the feedback control. If a negative determination is made in step S42, it is determined in step S44 that there is an abnormality in the arithmetic system for feedback control.

In addition, when an affirmative determination is made in step S42 or when the process of step S44 is completed, this series of processes is temporarily ended. Incidentally, when an abnormality is determined, for example, a process of turning off all switching elements g * # of the inverter INV (a shutdown process of the inverter INV), a process of notifying the HVECU 38, and the like are performed.
<Other embodiments>
Each of the above embodiments may be modified as follows.

About diagnostic estimation means
It is not limited to calculating the vector norm based on the current (actual current id, iq) on the dq axis, and for example, the norm of the current vector may be calculated on the αβ axis. At this time, the phase of the current vector may be calculated as a phase difference between the direction of the current vector and the direction advanced by 90 degrees from the d-axis direction determined from the rotation angle θ.

  Further, the effective power is not limited to calculating the effective power based on the current vector, the voltage vector, and the phase difference between them, and may be calculated based on, for example, the product of the voltage and current of each phase.

  Further, the present invention is not limited to the one provided with means for calculating the effective power and means for calculating the estimated torque for diagnosis Tde by dividing the calculated effective power by the electrical angular velocity ω. For example, a map that defines the relationship between the actual current vector norm Ia, norm Vn, phase difference Δ and electrical angular velocity ω and the estimated torque Tde for diagnosis is provided, and the vector norm Ia, norm Vn, phase difference Δ and electrical angular velocity ω May be used for map calculation of the estimated torque for diagnosis Tde.

"Control estimation means"
Not only the actual currents id and iq as input parameters, but the temperature of the motor generator 10 may be added to the input parameters, for example. Thereby, more accurate estimation can be performed in consideration of the temperature dependence of the d-axis inductance Ld and the q-axis inductance Lq.

  Not only the thing using a map but the above-mentioned formula (c1) may be used.

"About diagnostic tools"
The diagnosis based on the comparison between the estimated diagnosis torque Tde and the torque command value Tr may not be performed.

“Torque command value Tr”
The basic command value Tr0 is not limited to the correction amount Tlm for compensating the mechanical loss, the correction amount Tle for compensating the motor loss, and the correction amount Tb for compensating the load torque. For example, it may be corrected by only one of these three correction amounts. Further, for example, when the command from the HVECU 38 is a command value for the rotational speed, the torque command value Tr may be calculated in the MGECU 30 accordingly.

"AC voltage application circuit"
The AC voltage application circuit is not limited to a DC / AC conversion circuit (inverter INV) including a switching element that selectively connects a terminal of a rotating machine to each of a positive electrode and a negative electrode of a DC voltage source. For example, as described in Japanese Patent Application No. 2008-30825, a converter connected to each terminal of the rotating machine may be used.

"About rotating machines"
For example, it may be a main unit of a parallel series hybrid vehicle. Moreover, it is not limited to a hybrid vehicle, but may be a main unit mounted on an electric vehicle or a fuel cell vehicle that includes only means for accumulating electric energy as an energy supply source of the in-vehicle main unit. However, it is not limited to the main aircraft.

  As a synchronous machine provided with a permanent magnet, not only IPMSM but a surface magnet synchronous machine (SPMSM) etc. may be sufficient, for example.

  The rotating machine is not limited to a three-phase rotating machine, and may be a rotating machine having four phases or more, such as a five-phase rotating machine.

  In the above-described embodiment, the rotating machine is assumed to have a stator winding star-connected. However, the rotating machine is not limited to this and may be delta-connected.

  DESCRIPTION OF SYMBOLS 10 ... Motor generator, 16 ... Engine, 56 ... Torque estimation part for diagnosis.

Claims (4)

A detection value of a current flowing through the rotating machine is input, and control estimation means for estimating the torque of the rotating machine without using the electrical angular velocity information of the rotating machine is provided, and the torque estimated by the control estimation means is set as a command value. In a control device for a rotating machine that operates an output voltage of an AC voltage application circuit connected to the rotating machine for feedback control,
Based on the value obtained by dividing the output voltage to be operated, the detected value of the current flowing through the rotating machine, and the electrical angular speed of the rotating machine, and dividing the power of the AC voltage application circuit by the electrical angular speed of the rotating machine. Diagnostic estimation means for estimating the torque of
Diagnosing means for diagnosing the presence or absence of abnormality in the feedback control based on a comparison between the torque estimated by the diagnostic estimating means and the torque estimated by the control estimating means;
A control device for a rotating machine.   The input parameters of the diagnostic estimation means include a vector norm of the current flowing through the rotating machine and a phase difference between the current vector and the operated output voltage vector, and the current vector norm and the operated The torque of the rotating machine is estimated based on a value obtained by dividing the effective power of the AC voltage application circuit determined from the product of the output voltage and the phase difference by the electrical angular velocity of the rotating machine. The control device for a rotating machine according to claim 1.   The control device for a rotating machine according to claim 2, wherein the vector norm of the current is calculated from a dq coordinate component.   The diagnostic means further has a function of diagnosing the presence or absence of abnormality in torque control based on the degree of deviation between the torque estimated by the diagnostic estimation means and the command value. The control apparatus of the rotary machine of Claim 1.

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