JP2012114995A - Inverter controller and power conversion system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To correct an angle more accurately than before even when the variation of a rotation number such as acceleration and deceleration occurs within a prescribed period.SOLUTION: An inverter controller 60 includes: error correction means 67 for correcting an error between an ideal angle and a rotation angle on the basis of signal information related to the rotation angle of a rotary electric machine 40 outputted by a resolver 41 (first angle detector); reference angle detection means 66 for detecting a reference angle θs on the basis of the signal information outputted by the resolver 41; and reference cycle determination means 68 for determining a reference cycle Ts to be the reference of correcting the error with a detection angle θd on the basis of the reference angle θs detected by the reference angle detection means 66. The error correction means 67 estimates the ideal angle on the basis of the reference cycle Ts determined by the reference cycle determination means 68, and corrects the error between the estimated ideal angle and the detection angle θd detected on the basis of the signal information outputted by the resolver 41.

Description

  The present invention relates to an inverter control device and a power conversion system including an angle detector that outputs signal information related to a rotation angle, and error correction means that corrects an error in the rotation angle based on the signal information.

  Conventionally, an example of a technique related to an electric motor control device including a correction unit capable of correcting an error of a rotational position sensor is disclosed regardless of the control method (see, for example, Patent Document 1). According to this technique, the correction unit calculates a predicted value of the sensor value detected by the rotational position sensor, and corrects the sensor value detected by the rotational position sensor based on the calculated predicted value. The predicted value is calculated based on the average value of sensor values output from the rotational position sensor over a predetermined period, and the calculated average value. The predetermined period is a time required for the rotor to rotate an integral multiple of a certain angle (180 degrees, 90 degrees, 45 degrees, etc.).

  Here, the predicted value for correcting the sensor value according to Patent Document 1 is an average value of the sensor value in a predetermined period, and corresponds to a rotation angle per unit time. Since the start and end of the predetermined periods Δt1 and Δt2 shown in FIG. 3 of Patent Document 1 are timings at which the rotation angle becomes 0 degrees, it is considered that the predetermined period is defined by receiving the reference signal.

Japanese Patent No. 4059094

  However, when the technique of Patent Document 1 is applied, if the rotation speed (synonymous with “rotational speed”) varies due to acceleration or deceleration within a predetermined period, the average value of the predetermined period changes. However, since this average value is a numerical value that is applied over the entire predetermined period, when accelerating or decelerating within the predetermined period, the rotational change is erroneously recognized as an angle error, and the accurate There is a problem that the angle cannot be corrected.

  The present invention has been made in view of the above points, and an inverter control device capable of performing angle correction more accurately than in the past even when a fluctuation in the rotational speed such as acceleration or deceleration occurs within a predetermined period. And it aims at providing a power conversion system.

  The invention according to claim 1, which has been made to solve the above problem, corrects an error between the ideal angle and the rotation angle based on signal information relating to the rotation angle of the rotating electrical machine output by the first angle detector. In the inverter control device including the error correction means, the reference angle detection means for detecting a reference angle based on the signal information output by the first angle detector, and the reference angle detected by the reference angle detection means. Based on the reference period determined by the reference period determining means, the reference period determining means for determining a reference period serving as a reference for correcting the rotation angle error based on the ideal angle. And the detected angle of the rotating electrical machine detected based on the estimated ideal angle and the signal information output by the first angle detector, And correcting the errors.

  According to this configuration, the error correction unit estimates the ideal angle based on the reference period, and corrects the error between the ideal angle and the detected angle. Since the reference period is determined based on a reference angle (for example, an integer multiple of an angle such as 30 degrees or 45 degrees) detected by the reference angle detection means, fluctuations in the rotational speed such as acceleration and deceleration occur. Is not affected. Since the error correction performed by the error correction means is not affected by the fluctuation of the rotation speed, the error correction can be performed by separating the speed change and the error. Therefore, angle correction can be performed more accurately than in the past.

  The “rotary electric machine” corresponds to, for example, an electric motor (motor), a generator, a motor generator, and the like. “Rotation angle” means an angle from a reference position with respect to a rotating body (for example, a rotor) provided in the rotating electrical machine. The “signal information” may be analog information or digital information. The “angle detector” such as the first angle detector and the second angle detector described later is arbitrary as long as it is a detector that can directly or indirectly acquire the rotation angle. For example, a resolver, a rotary encoder, a gyroscope, a GMR (Giant Magnetoresistance Revolution) rotation sensor, and the like are applicable. The “ideal angle” means a rotation angle that changes ideally (that is, linearly or proportionally) as the rotating electrical machine rotates.

  The invention according to claim 2 is characterized in that the reference angle detection means detects one or both of the peak and zero cross of the signal information output by the first angle detector as a reference angle. According to this configuration, since the peak and zero crossing of the signal information can be specified by a simple circuit or discrimination method, the reference period determining means can accurately determine the reference period. Therefore, speed change and error can be separated with high accuracy, and error correction can be performed. Therefore, the error correction means can perform angle correction more accurately than in the past. “Peak” means the timing when the signal value of the signal information becomes the same value as the maximum value or the minimum value. “Zero cross” means the timing when the signal value of the signal information becomes zero.

  The invention according to claim 3 is characterized in that the reference angle detection means adjusts the angle error stored in a predetermined rotation speed range by the error correction means when detecting the reference angle. According to this configuration, the correct reference angle can be detected by canceling the error of the first angle detector.

  The invention according to claim 4 is characterized in that the reference angle detection means detects one or both of a peak of a counter electromotive voltage and a zero cross generated as the rotating electrical machine rotates as a reference angle. To do. According to this configuration, the peak of the back electromotive voltage and the zero crossing can be specified by a simple circuit or a discriminating method, so that the reference period determining means can accurately determine the reference period. Therefore, speed change and error can be separated with high accuracy, and error correction can be performed. Therefore, the error correction means can perform angle correction more accurately than in the past.

  The invention according to claim 5 includes a second angle detector that outputs a detection signal by magnetic pole detection of the rotating electrical machine separately from the first angle detector, and the reference angle detection means is the second angle detector. The reference angle is detected based on the detection signal output by the detector. According to this configuration, the second angle detector that is provided separately from the first angle detector outputs a detection signal by magnetic pole detection, so that even if fluctuations in the rotational speed such as acceleration and deceleration occur, there is no influence. Not receive. Therefore, the speed change and the error in the extremely low speed range can be separated with higher accuracy, and the error can be corrected. Therefore, angle correction can be performed more accurately than in the past.

  According to a sixth aspect of the present invention, in the power conversion system, the inverter control device according to any one of the first to fifth aspects and an inverter are provided. According to this configuration, even when the rotational speed fluctuates, such as acceleration or deceleration, within a predetermined period, the angle correction can be performed more accurately for the rotating electrical machine to be controlled than before.

It is a schematic diagram which shows the 1st structural example of a power conversion system. It is a schematic diagram which shows the 1st structural example of an inverter control apparatus. It is a figure explaining the process of calculating | requiring the correction value based on an ideal angle and a detection angle. It is a flowchart which shows the example of a procedure of a rotation angle correction process. It is a time chart which shows a time-dependent change concerning a detection angle, a rotation angle, etc. It is a schematic diagram which shows the 2nd structural example of a power conversion system. It is a schematic diagram which shows the 2nd structural example of an inverter control apparatus. It is a flowchart which shows the example of a procedure of a rotation angle correction process. It is a time chart which shows a time-dependent change concerning a detection angle, a rotation angle, etc. It is a schematic diagram which shows the 3rd structural example of a power conversion system. It is a schematic diagram which shows the 3rd structural example of an inverter control apparatus. It is a flowchart which shows the example of a procedure of a rotation angle correction process. It is a time chart which shows a time-dependent change concerning a detection angle, a rotation angle, etc.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. Unless otherwise specified, “connect” means electrical connection. Further, the continuous code is simplified using the symbol “˜”. For example, “switching elements Q1 to Q6” means “switching elements Q1, Q2, Q3, Q4, Q5, Q6”. Each figure shows elements necessary for explaining the present invention, and does not show all actual elements. When referring to directions such as up, down, left and right, the description in the drawings is used as a reference.

[Embodiment 1]
Embodiment 1 is an example in which a resolver is applied as a first angle detector to perform angle correction of a rotating electrical machine, and will be described with reference to FIGS. FIG. 1 is a schematic diagram illustrating a first configuration example of a power conversion system. FIG. 2 is a schematic diagram illustrating a first configuration example of the inverter control device. FIG. 3 is a diagram illustrating a process for obtaining a correction value based on the ideal angle and the detected angle. FIG. 4 is a flowchart showing a procedure example of the rotation angle correction process. FIG. 5 is a time chart showing changes with time of detection angle, rotation angle, and the like.

  The power conversion system shown in FIG. 1 includes a converter 10, an inverter 20, a control power supply circuit 50, an inverter control device 60, and the like. The converter 10 is provided as necessary, and converts a DC voltage (voltage value V1; for example, 300 [V]) supplied from a first DC power source E1 (for example, a battery) through a smoothing capacitor C1 to an inverter. It is responsible for the function of converting to a DC voltage (voltage value Vdc) required at 20 and outputting it. Since the configuration and operation of the converter 10 are well known, illustration and description are omitted.

  The inverter 20 has a function of converting a supplied DC voltage (voltage value Vdc; for example, 660 [V]) and outputting the converted voltage to the rotating electrical machine 40. A converter 10 is interposed between the first DC power supply E1 and the inverter 20. A smoothing capacitor C <b> 2 is connected between the converter 10 and the inverter 20. Capacitor C2 has a function of reducing potential fluctuations in the output voltage value (voltage value Vdc) of converter 10.

  The inverter 20 includes switching elements Q1 to Q6, diodes D1 to D6, and the like. As the switching elements Q1 to Q6, any semiconductor element having a switching function can be used, for example, an IGBT or a power transistor. The switching elements Q1 to Q6 are turned on / off in accordance with a control signal Sp transmitted individually from the inverter control device 60. Diodes D1-D6 are connected in parallel between the collector terminals and emitter terminals of switching elements Q1-Q6, respectively. These diodes D1 to D6 all function as freewheeling diodes. Switching elements Q1-Q3, diodes D1-D3, etc. are arranged on the upper arm side, and switching elements Q4-Q6, diodes D4-D6, etc. are arranged on the lower arm side. The common potential G1 is a common potential (same potential ground) in the inverter 20, and becomes 0 [V] when connected to the ground G2. Since the common potential G1 and the ground G2 may not necessarily be the same potential, they are indicated using different graphic symbols.

  The circuit elements in the inverter 20 are divided into three phases (U phase, V phase, W phase in this example) as shown by being surrounded by a one-dot chain line, and the operation is controlled for each phase by the inverter control device 60. The U phase is composed of switching elements Q1, Q4, diodes D1, D4, and the like. The V phase includes switching elements Q2 and Q5, diodes D2 and D5, and the like. The W phase includes switching elements Q3 and Q6, diodes D3 and D6, and the like. The U-phase switching elements Q1 and Q4 are connected in series to form a half bridge. Similarly, the V-phase switching elements Q2 and Q5 and the W-phase switching elements Q3 and Q6 are connected in series to form a half bridge. Each connection point of the half bridge and the three-phase terminal of the rotating electrical machine 40 are connected for each phase by lines Ku, Kv, Kw. A U-phase current Iu flows through the line Ku, a V-phase current Iv flows through the line Kv, and a W-phase current Iw flows through the line Kw.

  The control power supply circuit 50 converts the DC voltage V2 (for example, 12 [V], etc.) supplied from the second DC power supply E2 (for example, battery) into the voltage or current required by the converter 10, the inverter 20, or the like. Takes the function to output. Since the configuration and operation of the control power supply circuit 50 are well known, illustration and description thereof are omitted. These control power supply circuit 50 and second DC power supply E2 are both connected to ground G2 and grounded.

The inverter control device 60 manages the operation of the converter 10, the inverter 20, and the like. A configuration example of the inverter control device 60 for realizing the present invention will be described later (see FIG. 2). Signals input by the inverter control device 60 are output from the resolver 41, the command rotational speed N ^* transmitted from the ECU 70 corresponding to the external device, the current I (phase currents Iu, Iv, Iw) transmitted from the current sensor 30. Signal. The signal output from the inverter control device 60 includes a control signal Sp transmitted to the control terminals P1 to P6 of the switching elements Q1 to Q6, a control signal transmitted to a drive circuit provided in the converter 10, and the like.

The ECU 70 outputs a command rotational speed N ^* that commands the rotational speed in order to rotate the rotating electrical machine 40 at a target rotational speed. The ECU 70 corresponds to an “external device”.

  For the rotating electrical machine 40, for example, a three-phase motor (denoted as “M” in the figure) is applied. As the current sensor 30, a sensor capable of detecting each phase current (that is, phase currents Iu, Iv, Iw) flowing through the rotating electrical machine 40 is used. For example, a magnetic proportional sensor, an electromagnetic induction sensor, a Faraday effect sensor, a current transformer sensor, and the like are applicable. The resolver 41 corresponds to a “first angle detector” and outputs a signal based on a rotation angle of a rotor (for example, a main shaft or a rotor) provided in the rotating electrical machine 40. When the signal information based on the rotation angle is an analog signal such as the SIN detection signal Ss or the COS detection signal Sc, the signal information is converted into a digital signal such as the detection angle θd by the RD converter 80 and input to the inverter control device 60. .

  The above-described power conversion system is preferably provided in a transportation device that can realize movement by rotational driving of the rotating electrical machine 40. For example, automobiles, airplanes, ships, railway vehicles, and the like correspond to the transportation equipment.

  A configuration example of the inverter control device 60 will be described with reference to FIG. The inverter control device 60 shown in the block diagram in FIG. 2 includes joining means 61a and 61c, PI control means 61b, torque control means 61d, angular acceleration detection means 62, load torque estimation means 63, output torque calculation means 64, rotation A number calculation means 65, a reference angle detection means 66, an error correction means 67, a reference period determination means 68, and the like are included. Among these elements, the joining means 61a and 61c, the PI control means 61b, and the torque control means 61d realize the rotational speed feedback control.

The adding means 61a adds the input signals. In this example, in order to form a negative feedback loop, a difference value obtained by subtracting the detected rotational speed Ns from the command rotational speed N ^* is output as the deviation Ne. The PI control unit 61b calculates and outputs a torque command Te in order to perform PI control based on the deviation Ne output from the adding unit 61a and a proportional gain, an integral gain, or the like.

The adder 61c adds the input signals in the same manner as the adder 61a described above. Specifically, an added value obtained by adding the torque command Te output from the PI control unit 61b and the load torque Td output from the load torque estimating unit 63 is output as the final torque command T ^* . The torque control means 61d transmits a voltage command Vc corresponding to the final torque command T ^* to the inverter 20. The inverter 20 outputs a drive signal (including a modulation signal) for rotating the rotating electrical machine 40 based on the voltage command Vc output from the torque control means 61d.

  The load torque Td added by the adding means 61 c is estimated by the load torque estimating means 63. This load torque estimating means 63 is applied to the output torque To transmitted from the output torque calculating means 64, the angular acceleration ω transmitted from the angular acceleration detecting means 62, the detected rotational speed Ns transmitted from the rotational speed calculating means 65, and the like. Estimate based on.

  The angular acceleration detection means 62 has a function of detecting the angular acceleration ω of the rotating electrical machine 40. The detection method is arbitrary as long as the angular acceleration ω can be detected. In this example, the angular acceleration ω is estimated by performing a required calculation using the detected rotation speed Ns output from the rotation speed calculation means 65.

  The output torque calculation means 64 calculates the output torque To based on the current values of the currents detected by the current sensor 30 (for example, three-phase phase currents Iu, Iv, Iw). The calculation method can be arbitrarily set, and is calculated by calculating a mathematical model and estimating the output torque To, or by using a map with the current values of the phase currents Iu, Iv, and Iw flowing through the rotating electrical machine 40 as arguments. Or

  The reference angle detection unit 66 detects a reference angle θs for defining a correction section based on signal information (SIN detection signal Ss, COS detection signal Sc, etc.) output from the resolver 41. In this example, the reference angle θs at which the SIN detection signal Ss and the COS detection signal Sc become a zero value (or a peak value that reaches the peak) at which the zero crosses are detected. A specific detection example will be described later (see FIG. 5).

  When the reference angle θs is detected, an adjustment may be made with the angle error stored in the predetermined rotation speed range. The predetermined rotation speed range can be arbitrarily set. For example, the adjustment amount may be set at a constant rotational speed (specifically, every 100 [rpm], every 200 [rpm], every 1000 [rpm], etc.). To 100, 100 to 500, 500 to 2000, 2000 to 10,000 [rpm], etc.). The present invention may be applied to some predetermined rotation speed ranges, or may be applied to all predetermined rotation speed ranges.

  Based on the reference angle θs detected by the reference angle detection unit 66, the reference cycle determination unit 68 determines a reference cycle Ts that serves as a reference for correcting an error in the detection angle θd. A period indicated by the reference period Ts (for example, an angle of 45 degrees) corresponds to the correction section.

  The error correction means 67 estimates the ideal angle θi based on the reference period Ts determined by the reference period determination means 68, corrects the error between the estimated ideal angle θi and the detected angle θd, and outputs the rotation angle θr. .

  The rotation speed calculation means 65 calculates and outputs a detected rotation speed Ns indicating the rotation speed of the rotating electrical machine 40 based on the rotation angle θr output from the error correction means 67. If the rotation angle θr that changes during a certain period is known, the number of rotations can be easily obtained.

  A method of correcting the detection angle θd of the rotating electrical machine 40 in the inverter control device 60 configured as described above will be described with reference to FIGS. 3 and 4. First, as shown on the left side of FIG. 3, the ideal angle θi is an angle at which the rotation angle indicated by the vertical axis changes ideally (that is, linearly or proportionally) as the time indicated by the horizontal axis changes. On the other hand, the actually detected detection angle θd is an angle at which the rotation angle indicated by the vertical axis changes realistically (that is, non-linearly or non-proportionally) with respect to the time change indicated by the horizontal axis. . Since the detection angle θd is brought close to the ideal angle θi, an error obtained by subtracting the detection angle θd from the ideal angle θi is the correction value Am. The correction value Am indicated by a solid line or a two-dot chain line on the right side of FIG. 3 is recorded on the recording medium corresponding to each reference period Ts (correction section). The recording medium is provided in the inverter control device 60 or the like, and it is desirable to use a nonvolatile memory such as an EEPROM or a flash memory.

  In the rotation angle correction process shown in FIG. 4, first, the angle at which the signal information (SIN detection signal Ss or COS detection signal Sc) output from the resolver 41 becomes a zero value (or a peak value that reaches a peak) at which it crosses zero is used as a reference angle θs. [Step S10]. The reference angle θs corresponds to an integer multiple of 45 degrees, for example. In detecting the reference angle θs, the angle error stored in the predetermined rotation speed range may be adjusted.

  Next, a reference period Ts is determined based on the reference angle θs detected in step S10 [step S11], and an ideal angle θi is estimated based on the determined reference period Ts [step S12]. Further, an error between the ideal angle θi estimated at step S12 and the detected angle θd output from the RD converter 80 is detected [step S13], and the error of the detected angle θd is corrected with the correction value Am to output the rotation angle θr. [Step S14], the rotation angle correction process is returned.

  The change of the signal processed in the inverter control device 60 is as shown in FIG. 5, for example. In FIG. 5, in order from the top, the relationship between the detection angle θd and the true angle θt, the COS detection signal Sc, the SIN detection signal Ss, the reference period Ts, the relationship between the detection angle θd and the ideal angle θi, the error θe, and the rotation The time-dependent change concerning each angle θr is shown. On the horizontal axis indicating the angle, “NM” shown at 0 degrees (360 degrees) is an angle accompanying detection of the north marker.

  In the example shown in FIG. 5, the detection angle detected by the signal information output from the rotating electrical machine 40 as shown by the relationship between the detection angle θd (solid line) and the true angle θt (two-dot chain line) shown in the uppermost stage. It is assumed that θd does not coincide with the true angle θt. The COS detection signal Sc shown in the second stage and the SIN detection signal Ss shown in the third stage are each at an angle that is an integral multiple of 45 degrees. Therefore, the reference angle θs is 45, 90, 135, 180, 225, 270, 315, 360 degrees (step S10 in FIG. 4). The angle error is adjusted at a reference angle θs from 45 degrees to 315 degrees as indicated by “+ α1”, “+ α2”,..., “+ Α7”. According to this reference angle θs, the reference period Ts shown in the fourth stage is a period t1, which is 0 to 45 degrees, a period t2, which is 45 to 90 degrees, ..., a period t8 which is 315 to 360 degrees (step S11 in FIG. 4). ).

  When the ideal angle θi is estimated for each of the periods t1 to t8, a characteristic line as shown by a solid line in the fifth stage is obtained (step S12 in FIG. 4). If the detection angle θd indicated by a two-dot chain line changes, the error θe becomes a characteristic line as shown in the sixth stage (step S13 in FIG. 4). When the correction is made based on the error θe, the rotation angle θr becomes a characteristic line as shown at the bottom (step S14 in FIG. 4).

  According to the first embodiment described above, the following effects can be obtained. First, corresponding to claim 1, the inverter control device 60 includes a reference angle detection unit 66 that detects a reference angle θs based on signal information output from the resolver 41, and a reference angle θs that is detected by the reference angle detection unit 66. And a reference period determining means 68 for determining a reference period Ts that serves as a reference for correcting the error θe with respect to the detected angle θd. The error correcting means 67 has a reference period Ts determined by the reference period determining means 68. Based on this, the ideal angle θi is estimated, and an error θe between the estimated ideal angle θi and the detected angle θd of the rotating electrical machine 40 detected based on the signal information output by the resolver 41 is corrected (FIG. 1, FIG. 1). (See FIG. 2). According to this configuration, since the reference period Ts is determined based on the reference angle θs (an integer multiple of 45 degrees in the example of FIG. 5) detected by the reference angle detection unit 66, rotation such as acceleration and deceleration is performed. Even if the number fluctuates, it is not affected. Since the correction of the error θe performed by the error correction means 67 is not affected by the fluctuation of the rotational speed, the error correction can be performed by separating the speed change and the error. Therefore, angle correction can be performed more accurately than in the past.

  Corresponding to claim 2, the reference angle detection means 66 detects one or both of the peak and zero cross of the signal information output by the resolver 41 (that is, the COS detection signal Sc and the SIN detection signal Ss) as the reference angle θs. (See FIGS. 2 and 5). According to this configuration, the peak and zero crossing of the signal information can be specified with a simple circuit or discrimination method, so that the reference period determining means 68 can accurately determine the reference period Ts. Therefore, speed change and error can be separated with high accuracy, and error correction can be performed. Therefore, the error correction means 67 can perform angle correction more accurately than in the past.

  Corresponding to claim 3, the reference angle detection means 66 is configured to adjust the angle error stored in the predetermined rotation speed range by the error correction means 67 when detecting the reference angle θs. According to this configuration, the correct reference angle θs can be detected by canceling the error of the resolver 41.

  Corresponding to claim 6, the power conversion system includes the inverter control device 60 and the inverter 20 described above (see FIG. 1). According to this configuration, even when the rotational speed variation such as acceleration or deceleration occurs within a predetermined period, the angle correction can be performed more accurately for the rotating electrical machine 40 to be controlled than before.

[Embodiment 2]
The second embodiment is an example in which a resolver is applied as the first angle detector, and the reference angle is detected based on a counter electromotive voltage generated with the rotation of the rotating electrical machine. The second embodiment will be described with reference to FIGS. FIG. 6 is a schematic diagram illustrating a second configuration example of the power conversion system. FIG. 7 is a schematic diagram illustrating a second configuration example of the inverter control device. FIG. 8 is a flowchart showing a procedure example of the rotation angle correction process. FIG. 9 is a time chart showing changes with time of detection angle, rotation angle, and the like. For simplicity of illustration and description, the second embodiment will be described with respect to differences from the first embodiment. Therefore, the same elements as those used in Embodiment 1 are denoted by the same reference numerals, and description thereof is omitted.

  The power conversion system illustrated in FIG. 6 is a configuration example that replaces the power conversion system illustrated in FIG. 1. 1 is different from the configuration example of FIG. 1 in that a voltage sensor 35 that detects counter electromotive voltages Vuv, Vvw, and Vwu generated along with the rotation of the rotating electrical machine 40 is provided.

  The inverter control device 60 shown in FIG. 7 is a configuration example that replaces the inverter control device 60 shown in FIG. Although it is the same in that the reference angle detection means 66 is provided, the difference is that the input signal becomes the counter electromotive voltages Vuv, Vvw, Vwu output from the voltage sensor 35.

  The rotation angle correction process shown in FIG. 8 is a procedure example instead of the rotation angle correction process shown in FIG. The difference is that the reference angle θs is detected based on the back electromotive voltages Vuv, Vvw, Vwu output from the voltage sensor 35 instead of step S10 in FIG. 4 [step S20]. Of the back electromotive voltages Vuv, Vvw, and Vwu, the angle at which the two-phase back electromotive voltage crosses, the angle at which the remaining one phase peaks, and the like become the reference angle θs. In detecting the reference angle θs, the angle error stored in the predetermined rotation speed range may be adjusted as in the first embodiment.

  The time chart shown in FIG. 9 is a change with time instead of the time chart shown in FIG. Since the back electromotive voltages Vuv, Vvw, Vwu shown in the second stage are three-phase AC voltages, the angle at which the two phases cross and the angle at which the remaining one phase peaks are the reference angles θs. In the example of FIG. 9, an integer multiple of 30 degrees corresponds. Therefore, the reference angle θs is 30, 60, 90, 120, 150, 180, 210, 240, 270, 300, 330, 360 degrees (step S10 in FIG. 8). According to this reference angle θs, the reference period Ts shown in the third stage is a period t1 of 0 to 30 degrees, a period t2 of 30 to 60 degrees,..., A period t11 of 300 to 330 degrees, and a period t12 of 330 to 360 degrees. (Step S11 in FIG. 4).

  According to the second embodiment described above, the following effects can be obtained. Since claims 1, 3 and 6 are the same as in the first embodiment, the same effects as in the first embodiment can be obtained.

  Corresponding to claim 4, the reference angle detection means 66 detects one or both of the peaks and zero crosses of the back electromotive voltages Vuv, Vvw, Vwu generated as the rotating electrical machine 40 rotates as the reference angle θs. It was set as the structure (refer FIGS. 6-9). According to this configuration, the peak of the back electromotive voltage and the zero cross can be specified by a simple circuit or discrimination method, so that the reference period determining means 68 can accurately determine the reference period Ts. Therefore, speed change and error can be separated with high accuracy, and error correction can be performed. Therefore, the error correction means 67 can perform angle correction more accurately than in the past.

[Embodiment 3]
Embodiment 3 is an example in which a magnetic pole sensor is applied as a third angle detector to perform angle correction of a rotating electrical machine, and will be described with reference to FIGS. 10 to 13. FIG. 10 is a schematic diagram illustrating a third configuration example of the power conversion system. FIG. 11 is a schematic diagram illustrating a third configuration example of the inverter control device. FIG. 12 is a flowchart showing a procedure example of the rotation angle correction process. FIG. 13 is a time chart showing changes with time of detection angle, rotation angle, and the like. For simplicity of illustration and description, the third embodiment will be described with respect to differences from the first embodiment. Therefore, the same elements as those used in Embodiment 1 are denoted by the same reference numerals, and description thereof is omitted.

  The power conversion system shown in FIG. 10 is a configuration example that replaces the power conversion system shown in FIG. 1, and is different in the following two points. The first point includes a magnetic pole sensor 42 that outputs detection signals (magnetic pole signals Hu, Hv, Hw) by magnetic pole detection of the rotating electrical machine 40 separately from the resolver 41. The magnetic pole sensor 42 is a Hall sensor that is shifted every 120 degrees corresponding to the rotating electrical machine 40 that is a three-phase motor. Since the rotor of the rotating electrical machine 40 generally has magnetic poles (N pole and S pole), a pulse signal rises by a change from the N pole to the S pole and a change from the S pole to the N pole. Or fall. The second point includes a reference signal generation unit 90 that generates and outputs a reference signal St based on detection signals (magnetic pole signals Hu, Hv, Hw). The reference signal generation unit 90 detects, for example, rising and falling edges for each pulse signal of the magnetic pole signals Hu, Hv, and Hw, and generates and outputs a reference signal St.

  An inverter control device 60 shown in FIG. 11 is a configuration example that replaces the inverter control device 60 shown in FIG. 2. Although it is the same in that the reference angle detection unit 66 is provided, the difference is that the input signal becomes the reference signal St output from the reference signal generation unit 90.

  The rotation angle correction process shown in FIG. 12 is a procedure example that replaces the rotation angle correction process shown in FIG. The difference is that the reference angle θs is detected based on the reference signal St output from the magnetic pole sensor 42 via the reference signal generator 90 instead of step S10 in FIG. 4 [step S30]. In detecting the reference angle θs, the angle error stored in the predetermined rotation speed range may be adjusted as in the first embodiment.

  The time chart shown in FIG. 13 is a change with time instead of the time chart shown in FIG. Changes in detection signals (magnetic pole signals Hu, Hv, Hw) output from the magnetic pole sensor 42 are shown in the second stage. For any one of the magnetic pole signals Hu, Hv, and Hw, the angle at the time when the pulse signal rises and the angle at the time when the pulse signal falls become the reference angle θs. In the example of FIG. 13, the integer multiple of 30 degrees corresponds to the example of FIG.

  According to Embodiment 3 described above, the following effects can be obtained. Since claims 1, 3 and 6 are the same as in the first embodiment, the same effects as in the first embodiment can be obtained.

  Corresponding to claim 5, a magnetic pole sensor 42 that outputs a detection signal by magnetic pole detection of the rotating electrical machine 40 is provided separately from the resolver 41, and the reference angle detection means 66 is a detection signal (magnetic pole signal) output by the magnetic pole sensor 42. The reference angle θs is detected based on (Hu, Hv, Hw) (see FIGS. 10 to 13). According to this configuration, the magnetic pole signals Hu, Hv, and Hw output by the magnetic pole detection are not affected even when the rotational speed fluctuates such as acceleration or deceleration. Therefore, the speed change and the error in the extremely low speed range can be separated with higher accuracy, and the error can be corrected. Therefore, angle correction can be performed more accurately than in the past.

[Other Embodiments]
Although the form for implementing this invention was demonstrated according to Embodiment 1-3 in the above, this invention is not limited to the said form at all. In other words, various forms can be implemented without departing from the scope of the present invention. For example, the following forms may be realized.

  In the above-described first to third embodiments, a three-phase motor is applied as the rotating electrical machine 40 (see FIGS. 1, 6, and 10). Instead of this form, an electric motor having a number of phases other than three phases, a generator, or a motor generator can be applied. In the case of the rotating electrical machine 40 having a different number of phases, the reference angle θs and the reference period Ts vary depending on the number of phases. That is, an angle other than an integer multiple of 30 degrees or 45 degrees or a period may be obtained. Since only the control object is different and the rotation control is performed, the same effects as in the first to third embodiments can be obtained.

  In the first to third embodiments described above, the resolver 41 is applied to the first angle detector, and the magnetic pole sensor 42 is applied to the second angle detector (see FIGS. 1, 6, and 10). Instead of this form, other angle detectors that can directly or indirectly obtain the detection angle θd can be applied. Other angle detectors correspond to, for example, a rotary encoder, a gyroscope, a GMR rotation sensor, and the like. Since the detection angle θd can be obtained as a result even with other angle detectors, the same effects as in the first to third embodiments can be obtained.

In the above-described first to third embodiments, the configuration is such that the rotational speed feedback control is performed based on the command rotational speed N ^* transmitted from the external device (ECU 70) (see FIGS. 2, 7, 11, etc.). . Instead of this form, when the final torque command T ^* is transmitted from the external device and the inverter control device 60 controls the torque of the rotating electrical machine 40, the configuration may be such that torque feedback control is performed. In this case, each of the PI control means 61b and the torque control means 61d is configured to output a signal for performing torque control. Since only the difference between whether the rotational speed is to be controlled or whether the torque is to be controlled is the same effect as in the first to third embodiments.

  In the first to third embodiments described above, the PI control means 61b is configured to perform PI control including a proportional element and an integral element (see FIGS. 2, 7, 11, etc.). Instead of this form, PID control may be performed including a differential element. PID control is shown in parentheses in FIGS. Depending on the performance and application of the rotating electrical machine 40, the detected rotational speed Ns may change abruptly, and the response of the rotating electrical machine 40 is improved.

  In the first to third embodiments described above, the RD converter 80 and the reference signal generation unit 90 are provided separately from the inverter control device 60 (see FIGS. 2, 7, 11, etc.). Instead of this form, one or both of the RD converter 80 and the reference signal generator 90 may be provided in the inverter control device 60. Since this is merely a difference in configuration and the function is the same, it is possible to obtain the same effects as in the first to third embodiments.

10 Converter 20 Inverter (Power conversion system)
30 Current sensor 35 Voltage sensor 40 Rotating electric machine 41 Resolver (first angle detector)
42 Magnetic pole sensor (second angle detector)
50 Control power circuit 60 Inverter controller (Power conversion system)
61a, 61c Joining means 61b PI control means (or PID control means)
61d Torque control means 62 Angular acceleration detection means 63 Load torque estimation means 64 Output torque calculation means 65 Rotational speed calculation means 66 Reference angle detection means 67 Error correction means 68 Reference period determination means 70 ECU (external device)
80 RD converter 90 Reference signal generator Hu, Hv, Hw Magnetic pole signal (signal information)
Iu, Iv, Iw phase current (signal information)
Sc COS detection signal (signal information)
Ss SIN detection signal (signal information)
Vuv, Vvw, Vwu Back electromotive force (signal information)
θd Detection angle θs Reference angle Ts Reference period θr Rotation angle

Claims (6)

In the inverter control device comprising error correction means for correcting an error between the ideal angle and the rotation angle based on the signal information regarding the rotation angle of the rotating electrical machine output by the first angle detector.
Reference angle detection means for detecting a reference angle based on signal information output by the first angle detector;
Reference period determining means for determining a reference period serving as a reference for correcting an error in the rotation angle based on the reference angle detected by the reference angle detecting means;
The error correction means estimates the ideal angle based on the reference period determined by the reference period determination means, and detects based on the estimated ideal angle and signal information output by the first angle detector. An inverter control device that corrects an error from the detected angle of the rotating electrical machine.   2. The inverter control device according to claim 1, wherein the reference angle detection unit detects one or both of a peak and a zero cross of signal information output by the first angle detector as a reference angle.   3. The inverter control device according to claim 1, wherein the reference angle detection unit adjusts the angle error stored in a predetermined rotational speed range by the error correction unit when detecting the reference angle. 4.   4. The reference angle detection unit according to claim 1, wherein one or both of a peak of a back electromotive voltage and a zero cross generated as the rotating electrical machine rotates is detected as a reference angle. The inverter control device according to one item. Separately from the first angle detector, it has a second angle detector that outputs a detection signal by magnetic pole detection of the rotating electrical machine,
5. The inverter control according to claim 1, wherein the reference angle detection unit detects the reference angle based on the detection signal output by the second angle detector. 6. apparatus.   A power conversion system comprising: the inverter control device according to any one of claims 1 to 5; and an inverter.

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