JP6375103B2 - Rotating machine control device - Google Patents

Description

  The present invention relates to a control device for a rotating machine that manipulates at least the phase of the output voltage of the power converter so as to control the control amount of the rotating machine electrically connected to the power converter to its command value.

  As this type of control device, as seen in Patent Document 1 below, the output of a power converter (inverter) connected to the rotating machine is used to feedback control the torque of the rotating machine (AC motor) to its command value. Those that manipulate the phase of the voltage are known. Specifically, the control device includes a current detection unit that detects a current flowing through the rotating machine, a torque estimation unit that estimates the torque of the rotating machine based on the current detected by the current detection unit, and commands the estimated torque. A controller for calculating the phase of the output voltage is provided as an operation amount of the power converter for feedback control to the value.

JP 2000-50689 A

  Here, in the control system that controls the phase of the output voltage to control the torque of the rotating machine to the command value, the current flowing through the rotating machine is determined by the event. For this reason, there is a concern that the current that causes the failure of the rotating machine and the power converter flows in the rotating machine, and the reliability of the rotating machine and the power converter decreases.

  Moreover, in order to avoid that overcurrent flows into a rotary machine and a power converter, it is possible to restrict | limit the said command value with the value by which the reliability of a rotary machine and a power converter does not fall by overcurrent. However, a control system that controls the torque of the rotating machine to a command value is provided with a filter that removes noise and harmonic components of a signal (current signal) transmitted through the control system. For example, when the configuration in which the filter is provided between the current detection unit and the torque estimation unit is adopted, the torque estimated by the torque estimation unit becomes a large value corresponding to the overcurrent after the overcurrent actually starts to flow. The time until is longer than that in the configuration in which no filter is provided.

  For this reason, even when the command value is limited with a value that does not decrease the reliability of the rotating machine and the power converter, the phase of the output voltage is manipulated in the direction of decreasing the torque of the rotating machine after overcurrent begins to flow. It takes longer to start being. As a result, there is a concern that the time from when the overcurrent starts to flow until the overcurrent is reduced becomes longer, and the reliability of the rotating machine and the power converter decreases.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a control device for a rotating machine that can suitably avoid a decrease in reliability of the rotating machine and a power converter.

In order to solve the above problems, the present invention provides at least the output voltage of the power converter to control the control amount of the rotating machine (10) electrically connected to the power converter (20) to the command value. When normal operation means (30c, 30d, 30h, 30i; 30q-30v) for operating the phase and the current flowing through the rotating machine exceeds a threshold value, the operation of the phase by the normal operation means is prioritized. And priority operation means (30j, 30k; 30j, 30k, 30m, 30n, 30p; 30k, 30m, 30p, 30w) for operating the phase so that the current flowing through the rotating machine does not increase. .

  In the above invention, the control amount of the rotating machine is controlled to the command value by operating the phase by the normal operation means. Here, when a control system that controls the control amount of the rotating machine to the command value is provided with a filter that removes noise of a signal transmitted through the control system, the control amount is reduced after an overcurrent starts to flow through the rotating machine. The time until it becomes a large value corresponding to the overcurrent is lengthened. As a result, there is a concern that the reliability of the rotating machine and the power converter is lowered.

  Therefore, in the above invention, the priority operation means is provided. According to the priority operation means, when an overcurrent flows through the rotating machine and the current flowing through the rotating machine exceeds a threshold value, the phase is set so that the current flowing through the rotating machine does not increase in preference to the phase operation by the normal operation means. To operate. For this reason, the phase operation can be started earlier than the start timing by the normal operation means so that the current flowing through the rotating machine does not increase. Thereby, when an overcurrent flows through the rotating machine, the current flowing through the rotating machine can be quickly limited. Therefore, it is possible to suitably avoid a decrease in the reliability of the rotating machine and the power converter.

1 is an overall configuration diagram of a motor control system according to a first embodiment. The block diagram of the torque feedback control concerning the embodiment. 6 is a flowchart showing a procedure of voltage phase restriction processing according to the embodiment. The figure which shows the relationship of the torque and electric current amplitude with respect to a voltage phase. The block diagram of torque feedback control concerning a 2nd embodiment. 6 is a flowchart showing a procedure of voltage phase restriction processing according to the embodiment. The block diagram of the current feedback control concerning a 3rd embodiment. The block diagram of torque feedback control concerning a 4th embodiment. 6 is a flowchart showing a procedure of voltage phase restriction processing according to the embodiment. The block diagram of the torque feedback control concerning other embodiment.

(First embodiment)
DESCRIPTION OF EMBODIMENTS Hereinafter, a first embodiment in which a control device for a rotating machine according to the present invention is applied to a vehicle (for example, an electric vehicle or a hybrid vehicle) including a rotating machine as an in-vehicle main machine will be described with reference to the drawings.

  As shown in FIG. 1, the motor control system includes a motor generator 10, an inverter 20 as a “power converter”, a control device (hereinafter referred to as MGECU 30) that controls the motor generator 10, and a control device that controls vehicle control. (Hereinafter referred to as HVECU 40). The motor generator 10 is an in-vehicle main machine and is connected to drive wheels (not shown). In this embodiment, an embedded magnet synchronous machine (IPMSM) is used as the motor generator 10.

  The motor generator 10 is connected to a high voltage battery 22 as a “DC power supply” via an inverter 20. The output voltage of the high voltage battery 22 is, for example, 100 V or more. A smoothing capacitor 24 that smoothes the input voltage of the inverter 20 is provided between the high voltage battery 22 and the inverter 20.

  The inverter 20 includes a series connection body of a switching element S ¥ p (¥ = U, V, W) on the high potential side (upper arm side) and a switching element S ¥ n on the low potential side (lower arm side). . Specifically, the inverter 20 includes a series connection body of three sets of switching elements S ¥ p, S ¥ n, and the connection point of the switching elements S ¥ p, S ¥ n is connected to the ¥ phase of the motor generator 10. Yes. Incidentally, in the present embodiment, a voltage-controlled switching element is used as the switching element S ¥ # (# = p, n), and more specifically, an IGBT is used. A free wheel diode D ¥ # is connected in reverse parallel to the switching element S ¥ #.

  The motor control system further includes a V-phase current sensor 42V that detects a current flowing in the V-phase of the motor generator 10, a W-phase current sensor 42W that detects a current flowing in the W-phase of the motor generator 10, and an input voltage (high) of the inverter 20 A voltage sensor 44 that detects a DC voltage output from the voltage battery 22 and a rotation angle sensor 46 (for example, a resolver) that detects a rotation angle (electrical angle θ) of the motor generator 10 are provided.

  The MGECU 30 is composed mainly of a microcomputer, and operates the inverter 20 to feedback control the control amount (torque in the present embodiment) of the motor generator 10 to its command value (hereinafter, command torque Trq *). Specifically, the MGECU 30 generates an operation signal g ¥ # based on the detection values of the various sensors, and drives the generated operation signal g ¥ #, so that the switching element S ¥ # constituting the inverter 20 is turned on / off. Output to the circuit Dr ¥ # (gate drive circuit). Here, the operation signal g ¥ p on the upper arm side and the corresponding operation signal g ¥ n on the lower arm side are complementary to each other. That is, the switching element S ¥ p on the upper arm side and the corresponding switching element S ¥ n on the lower arm side are alternately turned on.

  The HVECU 40 is a vehicle-mounted control device that is provided outside the MGECU 30 and is higher than the MGECU 30. The HVECU 40 sets the command torque Trq * of the motor generator 10 based on the operation amount of the accelerator pedal that is the operation target of the user. HVECU 40 outputs the set command torque Trq * to MGECU 30. In the present embodiment, the HVECU 40 corresponds to “command value setting means”.

  Next, torque feedback control of the motor generator 10 executed by the MGECU 30 will be described with reference to FIG.

  The two-phase conversion unit 30a is based on the V-phase current iv detected by the V-phase current sensor 42V, the W-phase current iw detected by the W-phase current sensor 42W, and the electrical angle θ detected by the rotation angle sensor 46. The U-phase current iu, the V-phase current iv, and the W-phase current iw in the three-phase fixed coordinate system are converted into a d-axis current idr and a q-axis current iqr that are currents in the two-phase rotational coordinate system (dq coordinate system). The U-phase current iu may be calculated from the V-phase current iv and the W-phase current iw based on Kirchhoff's law.

  The speed calculation unit 30 b calculates the electrical angular speed ω based on the electrical angle θ detected by the rotation angle sensor 46.

  The command voltage calculation unit 30c receives the command torque Trq * and calculates a normalized voltage amplitude “Vn / ω”. Here, the normalized voltage amplitude “Vn / ω” is a value obtained by dividing the amplitude command value (hereinafter, voltage amplitude Vn) of the output voltage vector of the inverter 20 in the two-phase rotating coordinate system by the electrical angular velocity ω. . The amplitude V of the output voltage vector of the inverter 20 is defined as the square root of the sum of the square value of the d-axis component vd and the square value of the q-axis component of the output voltage vector. Further, the voltage amplitude Vn may be calculated using, for example, a map in which the command torque Trq * and the voltage amplitude Vn are related.

  The speed multiplication unit 30d calculates the voltage amplitude Vn by multiplying the normalized voltage amplitude “Vn / ω” by the electrical angular velocity ω.

  The first low-pass filter 30e removes a high-frequency component from the d-axis current idr calculated by the two-phase conversion unit 30a. The second low-pass filter 30f removes a high-frequency component from the q-axis current iqr calculated by the two-phase conversion unit 30a.

  The d-axis current idr and q-axis current iqr from which the high-frequency component has been removed are input to the torque estimator 30g. The torque estimator 30g calculates the estimated torque Te of the motor generator 10 based on the d-axis current idr from which the high-frequency component has been removed and the q-axis current iqr from which the high-frequency component has been removed. Here, the estimated torque Te may be calculated using a map storing the relationship between the d-axis current idr and q-axis current iqr and the estimated torque Te, or may be calculated using a model formula. In the present embodiment, the torque estimator 30g constitutes “torque estimation means”.

  The torque deviation calculation unit 30h calculates the torque deviation ΔT by subtracting the estimated torque Te from the command torque Trq *.

  Based on the torque deviation ΔT, the phase calculation unit 30i calculates a voltage phase (hereinafter referred to as FB voltage phase δfb) as an operation amount for performing feedback control of the estimated torque Te to the command torque Trq *. Specifically, the FB voltage phase δfb is calculated by proportional integral control using the torque deviation ΔT as an input. Here, the FB voltage phase δfb is increased (advanced) when the estimated torque Te is insufficient with respect to the command torque Trq *, and the FB voltage phase when the estimated torque Te is excessive with respect to the command torque Trq *. δfb is decreased (retarded). The FB voltage phase δfb is defined with the positive direction of the q axis as a reference, and the counterclockwise direction from this reference (the direction rotating from the positive direction of the q axis to the negative direction of the d axis) is defined as the positive direction. .

  In this embodiment, the command voltage calculation unit 30c, the speed multiplication unit 30d, the torque deviation calculation unit 30h, and the phase calculation unit 30i control the voltage amplitude Vn and FB in order to control the torque of the motor generator 10 to the command torque Trq *. “Normal operation means” for operating the voltage phase δfb is configured.

  The current amplitude calculation unit 30j calculates the amplitude In of the current vector based on the d-axis current idr and the q-axis current iqr calculated by the two-phase conversion unit 30a. Here, the amplitude In of the current vector is defined as the square root of the sum of the square value of the d-axis current idr and the square value of the q-axis current iqr.

  The voltage phase limiter 30k limits the FB voltage phase δfb calculated by the phase calculator 30i and outputs it to the operation signal generator 301. The voltage phase limiter 30k will be described in detail later.

  The operation signal generation unit 30l operates based on the voltage amplitude Vn output from the speed multiplication unit 30d, the FB voltage phase δfb output from the voltage phase limiter 30k, and the input voltage VINV detected by the voltage sensor 44. A signal g ¥ # is generated and output to the drive circuit Dr ¥ #.

  Specifically, the operation signal generation unit 301 first calculates the modulation factor M, which is a value obtained by normalizing the voltage amplitude Vn with the input voltage VINV. Specifically, the modulation factor M is calculated by dividing the voltage amplitude Vn by “½” of the input voltage VINV. Then, the operation signal generation unit 301 stores, for each modulation factor M, the waveform (pulse pattern) of the operation signal in the electrical angle θ1 period as map data. The operation signal generation unit 301 selects a pulse pattern corresponding to the calculated modulation factor M. Here, the pulse pattern is stored in advance in a memory 32 such as a ROM provided in the MGECU 30.

  When the pulse pattern is selected, the operation signal generation unit 301 generates the operation signal g ¥ # by setting the output timing of the pulse pattern based on the FB voltage phase δfb.

  Incidentally, in the present embodiment, when the modulation factor M is equal to or less than the first specified value Ma (for example, 1.15), the output voltage (specifically, the line voltage) of the inverter 20 is changed to a sine wave of the electrical angular velocity ω. The sine wave control is performed. On the other hand, in the case of an overmodulation region where the modulation factor M exceeds the first specified value Ma, overmodulation control is performed. In the overmodulation region, the amplitude or effective value of the fundamental wave component included in the output voltage of the inverter 20 is greater than the amplitude or effective value of the fundamental wave component included in the output voltage of the inverter 20 when the output voltage of the inverter 20 is a sine wave. Also grows. In particular, in the present embodiment, when the modulation factor M becomes a second specified value Mb (for example, 1.27) higher than the first specified value Ma, rectangular wave control (one pulse control) is performed. When rectangular wave control is performed, a period during which the high-potential side switching element S ¥ p is turned on and a period during which the low-potential side switching element S ¥ n is turned on in the period of the electrical angle θ1 is 1 as the pulse pattern. A pulse pattern (one pulse waveform) is selected each time.

  Subsequently, the voltage phase limiting process according to the present embodiment will be described. This process is executed by the MGECU 30 and is a process for avoiding a decrease in the reliability of the motor generator 10 and the inverter 20 when an overcurrent flows through the motor generator 10 and the inverter 20 due to a short circuit between the upper and lower arms. Specifically, when it is determined that the current amplitude In calculated by the current amplitude calculation unit 30j exceeds a predetermined value Iα (corresponding to “threshold”), the FB voltage phase δfb is set so that the current amplitude In does not increase with the highest priority. Process to operate.

  FIG. 3 shows the procedure of the voltage phase limiting process according to the present embodiment. This process is repeatedly executed by the MGECU 30 at a predetermined cycle, for example.

  In this series of processing, first, in step S10, it is determined whether or not the current amplitude In exceeds a predetermined value Iα. Here, the predetermined value Iα is, for example, a current capable of maintaining the reliability of the motor generator 10 and the switching element S ¥ # (phase current flowing through the motor generator 10 or current flowing through the switching element S ¥ # constituting the inverter 20 ) With a margin on the safe side.

  If an affirmative determination is made in step S10, the process proceeds to step S12, and the voltage phase limiter 30k is FB at the voltage phase when the current amplitude In exceeds the predetermined value Iα (when the positive determination is made in step S10). A limiting process for limiting the voltage phase δfb is performed. As a result, the advance angle of the FB voltage phase δfb is prohibited, and an increase in the current amplitude In is avoided. Here, by prohibiting the advance angle of the FB voltage phase δfb, an increase in the current amplitude In can be avoided, as shown in FIG. 4, when the FB voltage phase δfb is advanced, the current amplitude In increases. This is because, when the FB voltage phase δfb is retarded, the current amplitude In decreases (in the case of powering). 4A shows the relationship between the voltage amplitude Vn during power running, the FB voltage phase δfb under a certain rotational speed condition of the motor generator 10, and the torque of the motor generator 10. FIG. 4B shows the power running. FIG. 6 is a diagram illustrating a relationship between a voltage amplitude Vn with time, an FB voltage phase δfb, and a current amplitude In under a certain rotation speed condition of the motor generator 10;

  In the present embodiment, the current amplitude calculator 30j and the voltage phase limiter 30k constitute “priority operation means”.

  In the subsequent step S14, a command to decrease the command torque Trq * is issued to the HVECU 40. This process is a process for quickly eliminating the situation where an overcurrent flows through the motor generator 10 and the inverter 20. That is, in this embodiment, the command torque Trq * is input from the HVECU 40 that is an external device of the MGECU 30 to the MGECU 30. Here, even if the current amplitude In is limited by the voltage phase limiting process in which the MGECU 30 is the execution subject, if the HVECU 40 is not notified that the current amplitude In is limited, the HVECU 40 will operate the accelerator pedal. The command torque Trq * set based on the above is continuously output to the MGECU 30. In this case, for example, as long as the operation amount of the accelerator pedal does not become small, the situation where the current amplitude In tends to exceed the predetermined value Iα can be continued. In order to deal with these problems, the processing of this step is provided. In the present embodiment, the processing of this step constitutes “instruction means”.

  Returning to FIG. 3, in the subsequent step S <b> 16, notification processing for notifying the user that the torque of the motor generator 10 is limited is performed. Here, the notification process may be, for example, a process of turning on the MIL provided in the vehicle.

  When a negative determination is made in step S10 or when the process of step S16 is completed, this series of processes is temporarily terminated.

  According to the embodiment described in detail above, the following effects can be obtained.

  (1) When it is determined that the current amplitude In exceeds the predetermined value Iα, the voltage phase limiting unit 30k performs a limiting process for limiting the FB voltage phase δfb. Therefore, the FB voltage phase δfb can be limited so that the current amplitude In does not increase in preference to the operation of the FB voltage phase δfb by torque feedback control. Thereby, the operation of FB voltage phase δfb can be started earlier than the start timing by torque feedback control so that the current flowing through motor generator 10 does not increase. Thereby, when an overcurrent flows through motor generator 10 and inverter 20, the current flowing through motor generator 10 and inverter 20 can be quickly limited. Therefore, a decrease in reliability of motor generator 10 and inverter 20 can be suitably avoided.

  (2) In the period in which the current amplitude In is determined to exceed the predetermined value Iα, the HVECU 40 is instructed to decrease the command torque Trq *. Thereby, the situation where an overcurrent flows through motor generator 10 and inverter 20 can be quickly resolved.

(Second Embodiment)
Hereinafter, the second embodiment will be described with reference to the drawings with a focus on differences from the first embodiment.

  In the present embodiment, the voltage phase limiting process is changed.

  FIG. 5 shows a block diagram of torque feedback control according to the present embodiment. In FIG. 5, the same processes as those shown in FIG. 2 are denoted by the same reference numerals for the sake of convenience. In the present embodiment, the predetermined value Iα is referred to as a first predetermined value (corresponding to a “first threshold value”). Here, the setting method of the first predetermined value Iα according to the present embodiment is not limited to the same setting method as in the first embodiment. For example, the first predetermined value Iα may be set to the upper limit value of the current that can maintain the reliability of the motor generator 10 and the switching element S ¥ #, for example.

  As illustrated, the current deviation calculation unit 30m subtracts the current amplitude In from a second predetermined value Iβ (corresponding to a “second threshold value”) that is smaller than the first predetermined value Iα. ΔI is calculated.

  The integrator 30n calculates a voltage phase (hereinafter, limited voltage phase δs) by integral control based on the current deviation ΔI. The limit voltage phase δs is an operation amount for feedback control of the current amplitude In to the second predetermined value Iβ. The calculated limit voltage phase δs is output to the voltage phase limiter 30k and the switching unit 30p.

  The switching unit 30p selects, from the voltage phase limiting unit 30k or the integrator 30n, a voltage phase supply source to be input to the operation signal generating unit 301.

  Incidentally, in the present embodiment, the current amplitude calculating unit 30j, the voltage phase limiting unit 30k, the current deviation calculating unit 30m, the integrator 30n, and the switching unit 30p constitute “priority operation means”.

  Next, the voltage phase limiting process according to the present embodiment will be described with reference to FIG. Here, FIG. 6 is a flowchart showing the procedure of the above processing. This process is repeatedly executed by the MGECU 30 at a predetermined cycle, for example. In FIG. 6, the same steps as those shown in FIG. 3 are given the same step numbers for the sake of convenience.

  In this series of processes, if an affirmative determination is made in step S10, the process proceeds to step S18. In step S18, an instruction to decrease the command torque Trq * to the HVECU 40 is started. In step S20, notification to the user that the torque of motor generator 10 is limited is started.

  In subsequent step S22, the switching unit 30p is operated so that the limit voltage phase δs calculated by the integrator 30n is input to the operation signal generation unit 301. Here, in the present embodiment, the integrator 30n is operated only during a period in which the limit voltage phase δs is input to the operation signal generation unit 301 by operating the switching unit 30p. For this reason, when the processing of this step is executed, calculation of the limit voltage phase δs with the current deviation ΔI as an input is started in the integrator 30n.

  In the subsequent step S24, the process waits until it is determined that the current amplitude In has decreased to the second predetermined value Iβ. In the subsequent step S26, the current limit voltage phase δs output from the integrator 30n is set as the voltage phase reference value δsta.

  In subsequent step S28, the switching unit 30p is operated so that the FB voltage phase δfb calculated by the phase calculation unit 30i is input to the operation signal generation unit 301. Thereby, the operation of the integrator 30n is stopped, and the integrated value in the integrator 30n is reset.

  In the subsequent step S30, it is determined whether or not the FB voltage phase δfb calculated by the phase calculation unit 30i is equal to or less than the voltage phase reference value δsta. This processing is performed again when the current amplitude In is directed toward the first predetermined value Iα because the supply source of the voltage phase to be input to the operation signal generation unit 30l is switched from the integrator 30n to the phase calculation unit 30i. This is a process for avoiding a rising situation. That is, even when it is determined in step S24 that the current amplitude In has decreased to the second predetermined value Iβ, the FB voltage phase δfb output from the phase calculation unit 30i is still at a level at which overcurrent can be suppressed. It may not have dropped. In such a situation, when the supply source of the voltage phase to be input to the operation signal generation unit 30l is switched from the integrator 30n to the phase calculation unit 30i, the current amplitude In increases toward the first predetermined value Iα. In order to avoid such a situation, the processing of this step is provided.

  If a negative determination is made in step S30, the process proceeds to step S32, and the voltage phase limiter 30k limits the FB voltage phase δfb with the voltage phase reference value δsta. That is, while the FB voltage phase δfb is about to exceed the voltage phase reference value δsta, the FB voltage phase δfb is set to the voltage phase reference value δsta by the voltage phase limiter 30k. After the process of step S32 is completed, the process returns to step S30.

  Incidentally, in this embodiment, the voltage phase limiter 30k is not allowed to function in a period other than the period in which a negative determination is made in the process of step S30. For this reason, the FB voltage phase δfb calculated by the phase calculation unit 30i is not limited by the voltage phase limiting unit 30k in a period other than the period for which a negative determination is made in the process of step S30.

  On the other hand, if an affirmative determination is made in step S30, the process proceeds to step S34, where the command for reducing the command torque Trq * for the HVECU 40 is canceled, and the notification process to the user is canceled.

  Incidentally, when the process of step S34 is completed, or when a negative determination is made in step S10, the normal torque that generates the operation signal g ¥ # based on the FB voltage phase δfb calculated by the phase calculation unit 30i. Feedback control is performed.

  According to this embodiment described above, in addition to the effects obtained in the first embodiment, the following effects can be obtained.

  (3) When it is determined that the current amplitude In exceeds the first predetermined value Iα, the second current amplitude In is smaller than the first predetermined value Iα in preference to the voltage phase operation by the torque feedback control. The voltage phase was manipulated to a predetermined value Iβ. For this reason, when starting normal torque feedback control, the current flowing through motor generator 10 can be reduced to a safe level. Thereby, the fall of the reliability of the motor generator 10 and the inverter 20 can be avoided more suitably.

(Third embodiment)
Hereinafter, the third embodiment will be described with reference to the drawings with a focus on differences from the second embodiment.

  In this embodiment, instead of torque feedback control using torque as a direct control amount, current feedback control using current as a direct control amount is performed. Specifically, switching element S ¥ # is turned on / off so that the command current for realizing command torque Trq * matches the current flowing in motor generator 10. That is, in the present embodiment, the torque of the motor generator 10 becomes the final control amount, but in order to control the torque, the current flowing through the motor generator 10 is directly controlled as a control current. To do.

  FIG. 7 shows a block diagram of current feedback control according to the present embodiment. In FIG. 7, the same processes as those shown in FIG. 5 are given the same reference numerals for the sake of convenience.

  As shown in the figure, the command current calculation unit 30q is based on the command torque Trq * and the electrical angular velocity ω, and the d-axis command current id * that is the command value of the current in the two-phase rotating coordinate system, and the q-axis command current iq *. And calculate. The d-axis command current id * and the q-axis command current iq are, for example, using a map in which the command torque Trq * and the electrical angular velocity ω are associated with the d-axis command current id * and the q-axis command current iq. What is necessary is just to calculate.

  The d-axis deviation calculating unit 30r calculates the d-axis current deviation Δid by subtracting the d-axis current idr from the d-axis command current id *. On the other hand, the q-axis deviation calculating unit 30s calculates the q-axis current deviation Δiq by subtracting the q-axis current iqr from the q-axis command current iq *.

  The d-axis command voltage calculation unit 30t calculates a command voltage vd * on the d-axis as an operation amount for feedback control of the d-axis current idr to the d-axis command current id *. Specifically, the command voltage vd * on the d-axis is calculated by proportional-integral control based on the d-axis current deviation Δid. On the other hand, the q-axis command voltage calculation unit 30u calculates a command voltage vq * on the q-axis as an operation amount for performing feedback control of the q-axis current iqr to the q-axis command current iq *. Specifically, the command voltage vq * on the q axis is calculated by proportional integral control based on the q axis current deviation Δiq.

  The amplitude phase calculation unit 30v calculates the voltage amplitude Vn and the FB voltage phase δfb based on the d-axis command voltage vd * and the q-axis command voltage vq *. The voltage amplitude Vn is output to the operation signal generator 30l, and the FB voltage phase δfb is output to the voltage phase limiter 30k.

  In this embodiment, the command current calculation unit 30q, the d-axis deviation calculation unit 30r, the q-axis deviation calculation unit 30s, the d-axis command voltage calculation unit 30t, the q-axis command voltage calculation unit 30u, and the amplitude phase calculation unit 30v are “ "Normal operation means" is configured.

  Even in the current feedback control system described above, since the first low-pass filter 30e and the second low-pass filter 30f are provided, the overcurrent may not be quickly reduced. For this reason, according to this embodiment described above, an effect similar to the effect obtained in the first embodiment can be obtained.

(Fourth embodiment)
Hereinafter, the fourth embodiment will be described with reference to the drawings with a focus on differences from the second embodiment.

  In the present embodiment, the voltage phase limiting process is changed.

  FIG. 8 shows a block diagram of torque feedback control according to the present embodiment. In FIG. 8, the same processes as those shown in FIG. 5 are denoted by the same reference numerals for the sake of convenience.

  As illustrated, in the present embodiment, the current deviation calculation unit 30m and the integrator 30n are removed. In this embodiment, instead of these, a voltage phase gradual reduction unit 30w is provided. The voltage phase gradual decrease unit 30w receives the current amplitude In, the second predetermined value Iβ, and the FB voltage phase δfb. Incidentally, in the present embodiment, the current amplitude calculation unit 30j, the voltage phase limiting unit 30k, the switching unit 30p, and the voltage phase gradually decreasing unit 30w constitute “priority operation means”.

  Next, the voltage phase limiting process according to the present embodiment will be described with reference to FIG. Here, FIG. 9 is a flowchart showing the procedure of the above processing. This process is repeatedly executed by the MGECU 30 at a predetermined cycle, for example. In FIG. 9, the same steps as those shown in FIG. 6 are given the same step numbers for the sake of convenience.

  In this series of processes, when an affirmative determination is made in step S10, the process proceeds to steps S36, S38, and S24 via steps S18 to S22. In these steps, the FB voltage phase δfb when an affirmative determination is made in step S10 is set to the initial value δ1, and the initial value δ1 is set for each control period until it is determined that the current amplitude In has decreased to the second predetermined value Iβ. Is subtracted by a predetermined amount Δ (for example, 2 °). Then, the value subtracted for each control cycle is output as the limit voltage phase δs. This process is performed in the voltage phase gradual reduction unit 30w. According to this process, the limit voltage phase δs gradually decreases from the initial value δ1 until an affirmative determination is made in step S24.

  If a negative determination is made in step S10, or if the process of step S34 is completed, this series of processes is temporarily terminated.

  According to the present embodiment described above, the same effect as that of the third embodiment can be obtained.

(Other embodiments)
Each of the above embodiments may be modified as follows.

  The installation position of the low-pass filter in the feedback control system is not limited to that exemplified in the first embodiment. For example, as shown in FIG. 10, the first low-pass filter 30e and the second low-pass filter 30f may be removed, and a low-pass filter 30x that removes high-frequency components from the estimated torque may be provided on the output side of the torque estimator 30g. Good.

  The method for calculating the current amplitude In is not limited to the method shown in the above embodiments. For example, the amplitude of the primary component included in the phase current of the motor generator 10 may be calculated by the FFT as the current amplitude In. Further, for example, the current amplitude In may be calculated based on the peak value of one phase of the phase current or the effective value of the phase current. Further, the parameter used for limiting the voltage phase is not limited to the current amplitude In, but may be the peak value or the effective value.

  The application target of the present invention is not limited to a control system that feedback-controls a controlled variable (torque or current in a two-phase rotating coordinate system) to its command value, but is a control system that feed-forward-controls a controlled variable to the command value. May be.

  -"Rotating machine" is not limited to IPMSM, but may be a surface magnet synchronous machine (SPMSM) or a wound field type synchronous machine. Here, for example, when the SPMSM is employed in the first embodiment, since the torque of the rotating machine is determined by the q-axis current, the control system is substantially configured by current feedback control.

  Further, the “rotating machine” is not limited to a synchronous machine and may be, for example, an induction machine. Furthermore, the “rotating machine” is not limited to being used as an in-vehicle main machine, but may be used as an in-vehicle auxiliary machine such as an electric power steering device or an electric motor constituting an air-conditioning electric compressor. In addition, the “rotating machine” is not limited to a vehicle-mounted type.

  DESCRIPTION OF SYMBOLS 10 ... Motor generator, 20 ... Inverter, 30 ... MGECU.

Claims (4)

Torque estimating means (30g) for estimating the torque of the rotating machine as a control amount of the rotating machine based on a current flowing through the rotating machine (10) electrically connected to the power converter (20) ;
Filters (30e, 30f) for removing high-frequency components from the current used for estimation of torque as the control amount in the torque estimation means;
An FB voltage phase that is a phase of the output voltage of the power converter is calculated as an operation amount for feedback control of the estimated control amount to the command value, and the power conversion is performed based on the calculated FB voltage phase. Normal operating means (30c, 30d, 30h, 30i ) for operating the vessel ;
When the current from which the high-frequency component is not removed by the filter exceeds a first threshold value, the current from which the high-frequency component is not removed by the filter becomes a second threshold value that is smaller than the first threshold value. Calculating a limiting voltage phase that is a phase of the output voltage that reduces the current from which the high frequency component has not been removed by the filter, and replacing the calculated FB voltage phase by the normal operation means with the calculated limiting voltage Priority operating means ( 30j, 30k, 30m, 30n, 30p; 30k, 30m, 30p, 30w) for operating the power converter based on the voltage phase ;
A control device for a rotating machine. Torque estimation means (30g) for estimating the torque of the rotating machine based on the current flowing through the rotating machine (10) electrically connected to the power converter (20) ;
A filter (30x) for removing high-frequency components from the torque estimated by the torque estimating means;
The torque from which the high frequency component has been removed by the filter is used as a control amount of the rotating machine, and an FB voltage phase that is a phase of the output voltage of the power converter is used as an operation amount for feedback control of the control amount to its command value Normal operation means (30c, 30d, 30h, 30i) for operating the power converter based on the calculated FB voltage phase;
When the current from which the high-frequency component has not been removed by the filter that removes the high-frequency component exceeds the first threshold, the current from which the high-frequency component has not been removed becomes a second threshold that is smaller than the first threshold. Until it becomes, the limit voltage phase that is the phase of the output voltage that reduces the current from which the high-frequency component is not removed is calculated, and the calculated limit is replaced with the FB voltage phase calculated by the normal operation means. Priority operating means (30j, 30k, 30m, 30n, 30p; 30k, 30m, 30p, 30w) for operating the power converter based on the voltage phase;
A control device for a rotating machine. Filters (30e, 30f) for removing high-frequency components from the current of the two-phase rotating coordinate system flowing in the rotating machine (10) electrically connected to the power converter (20) ;
The current from which the high-frequency component has been removed by the filter is used as the control amount of the rotating machine, and the FB voltage that is the phase of the output voltage of the power converter is used as an operation amount for feedback control of the control amount to its command value Normal operation means (30q-30v) for calculating a phase and operating the power converter based on the calculated FB voltage phase;
If the current pre-Symbol high frequency component is not removed by the filter exceeds a first threshold value, the current high-frequency component is not removed is smaller second threshold than said first threshold value by the filter Until, the limit voltage phase which is the phase of the output voltage that reduces the current from which the high frequency component has not been removed by the filter is calculated, and the calculated FB voltage phase is replaced with the FB voltage phase calculated by the normal operation means. Priority operating means (30j, 30k, 30m, 30n, 30p) for operating the power converter based on a limiting voltage phase;
A control device for a rotating machine. The normal operation means is provided outside the control device, and the command value set by the command value setting means for setting the command value is input,
The apparatus further comprises instruction means for instructing the command value setting means to reduce the command value when the current from which the high frequency component has not been removed by the filter exceeds the first threshold value. Item 4. The control device for a rotating machine according to any one of Items 1 to 3 .

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