JP2012090361A - Controller for rotary machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the following problem: there occur many man-hours for matching processing means for determining the presence/absence of demagnetization of a motor generator 10 having a permanent magnet.SOLUTION: A motor generator 10 is mechanically connected to a driving wheel 14 through a clutch C1 and is mechanically connected to an engine 16 through a clutch C2. Immediately after a vehicle start switch is turned on, the torque of the motor generator 10 is controlled by current feedback control with the clutches C1, C2 released and, when actual torque obtained at this time is lower than request torque, it is determined that the magnetic flux of a permanent magnet is on a decrease.

Description

  The present invention relates to a control device for a rotating machine that controls a control amount of the rotating machine including a permanent magnet.

  In this type of control device, for example, as shown in Patent Document 1 below, a device that determines the presence or absence of so-called demagnetization in which the magnetic flux of the permanent magnet decreases has been proposed. Specifically, when operating a command voltage as an operation amount for performing current feedback control so that a command current corresponding to a required torque for a three-phase motor is obtained, whether or not demagnetization is performed based on a difference between the command voltage and a reference value Judging. Here, the reference value is calculated by a map in which a value is determined for each of a plurality of values for each of the rotation speed and torque of the three-phase motor.

Japanese Patent No. 4223880

  By the way, the adaptation of the map for obtaining the reference value requires a great amount of man-hours. In addition, the accuracy of demagnetization may be reduced during transition.

  The present invention has been made in the process of solving the above-described problems, and an object thereof is to provide a new control device for a rotating machine that can suitably determine the presence or absence of demagnetization of the rotating machine including a permanent magnet. There is.

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

  According to a first aspect of the present invention, there is provided a control device for a rotating machine that controls a control amount of a rotating machine including a permanent magnet, and a torque control unit that controls a torque of the rotating machine to a command value having an absolute value larger than zero. A load torque acquisition means for acquiring information relating to the load torque applied to the rotating machine, and information relating to the actual torque of the rotating machine at the time of control by the torque control means, with the information relating to the acquired load torque being input. And demagnetizing determination means for determining whether or not the magnetic flux of the permanent magnet is decreased.

  In the said invention, the actual torque of a rotary machine can be grasped | ascertained with high precision by using the information regarding load torque. For this reason, it is possible to calculate the parameter related to the actual torque with high accuracy according to the load torque, or to calculate the determination value to be compared with the parameter related to the actual torque with high accuracy according to the load torque. As a result, the presence or absence of a decrease in the magnetic flux of the permanent magnet can be suitably determined.

  According to a second aspect of the present invention, in the first aspect of the present invention, the rotating machine is an in-vehicle main machine, and further includes driving wheel side blocking means for blocking transmission of power between the rotating machine and the driving wheel. The load torque acquisition unit operates the drive wheel side blocking unit to block transmission of power between the rotating machine and the driving wheel, thereby applying a load applied to the rotating machine from the driving wheel side. The information indicating that the torque is zero is acquired, and the demagnetization determining unit is configured to transmit the power between the rotating machine and the driving wheel by the driving wheel side blocking unit. The presence or absence of a decrease in the magnetic flux of the permanent magnet is determined based on an actual torque parameter.

  In the said invention, the actual torque of a rotary machine can be grasped | ascertained easily by setting it as the state from which a load torque is not provided to a rotary machine from the drive wheel side.

  The invention according to claim 3 is the invention according to claim 2, wherein the vehicle on which the control device is mounted includes an internal combustion engine as an in-vehicle main machine in addition to the rotary machine, and the rotary machine and the internal combustion engine Engine-side shut-off means for shutting off the transmission of power between them, and the load torque acquisition means operates the engine-side shut-off means to shut off the power transmission between the rotating machine and the internal combustion engine. The information indicating that the load torque applied to the rotating machine is zero from the internal combustion engine side is obtained, and the demagnetization determining means is configured such that the engine-side blocking means causes the rotating machine and the internal combustion engine to The presence or absence of a decrease in the magnetic flux of the permanent magnet is determined based on a parameter relating to the actual torque in a state where the transmission of power between the permanent magnets is interrupted.

  In the above invention, the actual torque of the rotating machine can be easily grasped by setting the load torque to be not applied to the rotating machine from the internal combustion engine side.

  According to a fourth aspect of the invention, in the invention according to any one of the first to third aspects, the parameter relating to the actual torque of the rotating machine is a value of the torque of the rotating machine.

  According to a fifth aspect of the present invention, in the fourth aspect of the invention, the demagnetizing determination unit further includes torque estimation means for estimating the torque of the rotating machine by using information on a change in the rotation angle of the rotating machine as an input. The torque estimated by the torque estimating means is used as a parameter relating to the actual torque of the rotating machine.

  Torque is a factor that causes angular acceleration. For this reason, the torque can be dynamically estimated by using the change in the rotation angle. In the above invention, in view of this point, the input parameter of the torque estimating means is selected.

  According to a sixth aspect of the present invention, in the fifth aspect of the present invention, the torque estimating means multiplies the rotation axis of the rotating machine and the moment of inertia of the rotating body rotating in conjunction with the rotation acceleration of the rotating machine. It is a dynamic model having the terms described above.

  In the above invention, by using the dynamic model, the torque estimation means can be configured only by acquiring the value of the moment of inertia or the like of the member connected to the rotating machine, so that the construction of the torque estimation means is facilitated. .

  The invention according to claim 7 is the invention according to claim 4, wherein the parameter relating to the actual torque of the rotating machine is an output of a torque detector for detecting the torque of the rotating machine.

  In the said invention, the calculation load concerning acquisition of the parameter regarding actual torque can be reduced by acquiring the output of a torque detector.

  The invention according to claim 8 is the invention according to any one of claims 1 to 3, wherein the parameter relating to the actual torque of the rotating machine relates to a changing speed of the rotating speed of the rotating machine. Features.

  Torque is a factor that causes angular acceleration. For this reason, the changing speed of the rotational speed can be information on the actual torque.

  The invention according to claim 9 is the invention according to claim 8, wherein the parameter relating to the actual torque of the rotating machine is an angular acceleration of the rotating machine.

  According to a tenth aspect of the present invention, in the eighth aspect of the invention, the parameter relating to the actual torque of the rotating machine is the rotational speed of the rotating machine when a predetermined time has elapsed from the start of the torque control by the torque control means. It is characterized by being.

  In the above invention, by using the rotation speed at the time when the predetermined time has elapsed, it is possible to acquire information corresponding to the angular acceleration while avoiding the differential calculation processing for calculating the angular acceleration.

  According to an eleventh aspect of the present invention, in the invention according to the eighth aspect, the parameter relating to the actual torque of the rotating machine is such that the rotational speed of the rotating machine is equal to a specified speed after the torque control means starts controlling the torque. It is the time required to become.

  In the above invention, by using the time required for the rotational speed to reach the specified speed, it is possible to acquire information corresponding to the angular acceleration while avoiding the differential operation processing for calculating the angular acceleration.

  A twelfth aspect of the invention is the invention according to any one of the eighth to eleventh aspects, wherein the parameter relating to the actual torque of the rotating machine is an output of a rotation angle detector of the rotating machine or the rotation angle. The output of the estimator is used.

  A thirteenth aspect of the present invention is the method according to any one of the first to twelfth aspects, further comprising setting means for setting a determination value corresponding to a torque command value for the rotating machine with respect to the torque-related parameter. And the demagnetization determining means determines whether or not there is a decrease in the magnetic flux of the permanent magnet based on a comparison between a parameter relating to the actual torque and the determination value.

  According to a fourteenth aspect of the present invention, in the invention according to the thirteenth aspect, the setting means is responsive to a temperature of the rotating machine when a parameter relating to the actual torque used for the determination by the demagnetization determining means is acquired. The determination value used by the demagnetization determination means is variably set.

  The magnetic flux of the permanent magnet can change depending on the temperature. In view of this point, the above invention can improve the accuracy of determining whether or not there is a decrease in magnetic flux by variably setting the determination value according to the temperature.

  According to a fifteenth aspect of the present invention, in the invention according to the thirteenth or fourteenth aspect, the setting means is a parameter relating to the actual torque when the torque control means is controlled during initial use of the rotating machine. The determination value is set based on this.

  In the above invention, the man-hour required for setting the judgment value can be reduced by setting the judgment value based on the parameter relating to the actual torque when it is assumed that the magnetic flux is not reduced.

  The invention according to claim 16 is the invention according to any one of claims 1 to 12, wherein the demagnetization determining means is configured to reduce the magnetic flux of the permanent magnet based on a change speed of a parameter relating to the actual torque. It is characterized by judging.

  A situation in which the magnetic flux of the permanent magnet decreases at a level that cannot be ignored usually occurs abruptly when the control of the rotating machine fails. In view of this point, the above invention uses the change speed of the parameter relating to the actual torque.

  The invention according to claim 17 is the invention according to any one of claims 1 to 16, wherein the rotating machine is an in-vehicle main machine, and the rotating machine receives power from a power supply source via a power conversion circuit. A relay is connected between the power conversion circuit and the power supply source, and the torque is controlled by the torque control means in a state in which the relay is connected. The presence or absence of a decrease in the magnetic flux of the permanent magnet is determined on the basis of a parameter relating to the actual torque during the operation.

  In the state where the relay is connected, the output of the rotating machine can be easily increased, so that the torque generated in the rotating machine can be increased. For this reason, the determination accuracy of the presence or absence of a decrease in magnetic flux can be improved.

  The invention according to claim 18 is the invention according to any one of claims 1 to 17, wherein the rotating machine has saliency, and the torque control means commands a current of the rotating machine. The torque of the rotating machine is controlled to its command value by controlling to a value, and the current command value of the current is zero in the d-axis direction.

  In the case of a rotating machine having saliency, reluctance torque is generated in addition to magnet torque, and in order to detect a decrease in magnet torque with high accuracy, it is necessary to grasp reluctance torque with high accuracy. In the above invention, in view of this point, the demagnetization determination process can be performed while the reluctance torque is set to zero by setting the current in the d-axis direction to zero.

1 is a system configuration diagram according to a first embodiment. FIG. The block diagram regarding the demagnetization judgment process of the embodiment. The flowchart which shows the procedure of the said demagnetization judgment process. The block diagram regarding the demagnetization judgment process concerning 2nd Embodiment. The flowchart which shows the procedure of the demagnetization judgment process concerning 3rd Embodiment. The flowchart which shows the procedure of the demagnetization judgment process concerning 4th Embodiment. The flowchart which shows the procedure of the demagnetization judgment process concerning 5th Embodiment. The flowchart which shows the procedure of the demagnetization judgment process concerning 6th Embodiment. The flowchart which shows the procedure of the demagnetization judgment process concerning 7th Embodiment. The system block diagram concerning the modification of each said embodiment.

<First Embodiment>
Hereinafter, a first 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. That is, the rotating shaft 10 a of the motor generator 10 is mechanically connected to the drive wheels 14 via the electronically controlled clutch C 1 and the 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 clutch C1 is a wet type and the clutch C2 is a dry type. The clutches C1 and C2 and the transmission 12 are supplied with lubricating oil (oil) by an oil pump 18. The oil pump 18 uses the power of the rotating shaft 10a of the motor generator 10 as a drive source.

  The control device 30 operates these to control the control amount of the engine 16, the control amount of the motor generator 10, and further the control amount of the transmission 12. Specifically, the power control unit 20 is operated to control the control amount of the motor generator 10. Further, the control device 30 performs the engagement operation and the release operation of the clutches C1 and C2.

  FIG. 2 shows the motor generator 10 and the power control unit 20 and part of the processing performed by the control device 30.

  Each phase of the illustrated motor generator 10 is connected to a capacitor 22 via an inverter IV, and a secondary battery (high voltage) as a DC power source is connected via the inverter IV and relays SMR1, SMR2, and SMR3. It is connected to a voltage battery 24). Here, the high voltage battery 24 has a terminal voltage of, for example, 100 V or more.

  The inverter IV 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, V, Each is connected to the W phase. In the present embodiment, insulated gate bipolar transistors (IGBTs) are used as the switching elements S * p and S * n. A diode D * # is connected in antiparallel to each of the switching elements S * # (# = p, n).

  In the present embodiment, the following are provided as means for detecting (estimating) the state of the motor generator 10 and the inverter IV. First, a voltage sensor 25 for detecting a voltage between input terminals of the inverter IV is provided. Further, a current sensor 26 that detects currents iu, iv, and iw flowing through the phases of the motor generator 10 is provided. Further, a temperature sensor 27 for detecting the temperature of the permanent magnet provided in the motor generator 10 is provided.

  Furthermore, an angle information output unit 28 is provided as means for acquiring information related to the electrical angle (rotation angle θ) of the motor generator 10. The angle information output unit 28 may be a rotation angle detector such as a resolver, for example. Further, for example, a rotation angle estimator that estimates the rotation angle based on the electrical state quantity of the motor generator 10 may be used. This estimator is described in, for example, “Extended induced voltage observer for sensorless control of salient pole type brushless DC motor No. 1026 in 1999 National Institute of Electrical Engineers of Japan” in the high rotation speed region of the motor generator 10. It may be an observer. Further, in the low rotation speed region of the motor generator 10, for example, as described in Japanese Patent Application Laid-Open No. 2009-148017, the rotation angle is estimated based on the current response when a harmonic signal higher than the electrical angular frequency is superimposed. It may be a means to do.

  Next, processing relating to control of the control amount of the motor generator 10 performed by the control device 30 will be described.

  The dq converter 31 converts each phase current iu, iv, iw detected by the current sensor 26 into a d-axis current id and a q-axis current iq, which are currents in the rotating coordinate system. The command current setting unit 32 sets a command current idr on the d axis and a command current iqr on the q axis in the rotational coordinate system (dq coordinate system) based on the required torque Tr. Here, it is desirable that the command currents idr and iqr are for performing the minimum current and maximum torque control for realizing the maximum torque with the minimum current.

  The feedback control unit 34 calculates the d-axis command voltage vdr as an operation amount for performing feedback control of the d-axis current id to the command current idr by the proportional controller and the integral controller. On the other hand, the feedback control unit 36 calculates the q-axis command voltage vqr as an operation amount for performing feedback control of the q-axis current iq to the command current iqr by the proportional controller and the integral controller.

  The three-phase conversion unit 38 converts the command voltages vdr and vqr to the U-phase command voltages Vur and V-phase, which are the command voltages in the three-phase fixed coordinate system, based on the rotation angle θ output by the angle information output unit 28. Are converted into a command voltage Vwr of W and a command voltage Vwr of the W phase. The PWM modulation unit 40 generates a PWM signal for setting the three-phase output voltage of the inverter IV to a voltage that simulates the command voltages Vur, Vvr, and Vwr. Here, for example, the result of comparing the command voltages Vur, Vvr, Vwr with the input voltage of the inverter IV detected by the voltage sensor 25 and the triangular wave carrier may be used as the PWM signal. The PWM signal generated thereby is an operation signal g * # for operating the switching element S * # (* = u, v, w; # = p, n) of the inverter IV.

  In the command current setting unit 32, command currents idr and iqr are set so as to satisfy the required torque Tr. Here, when the torque T of the IPMSM uses a d-axis inductance Ld, a q-axis inductance Lq, a d-axis current id, a q-axis current iq, an armature flux linkage constant φ and a pole pair number P, the following formula ( c1) is used.

T = P {φiq + (Ld−Lq) id · iq} (c1)
However, when so-called demagnetization occurs in which the magnetic flux of the permanent magnet is reduced, the armature flux linkage constant φ is reduced from that assumed in the setting of the command current setting unit 32. For this reason, even if the current flowing through the motor generator 10 can be controlled to the command currents idr and iqr, the actual torque of the motor generator 10 becomes smaller than the required torque Tr. When the actual torque decrease is significant, various problems such as a reduction in the efficiency of the motor generator 10 occur. Therefore, in the present embodiment, as shown in the figure, a demagnetization determining unit 52 is provided, and when it is determined that the magnetic flux of the permanent magnet of the motor generator 10 is decreased, this is notified to the outside. Specifically, in the demagnetization determination unit 52, the rotation speed ω calculated by the speed calculation unit 50 based on the rotation angle θ output from the angle information output unit 28 and the temperature TH detected by the temperature sensor 27 are input. Determine the presence or absence of demagnetization.

  FIG. 3 shows a procedure of processing performed by the demagnetization determination unit 52. This process is repeatedly executed at a predetermined cycle, for example.

  In this series of processes, first, in step S10, it is determined whether or not the start switch of the vehicle has been switched to the on state. Here, the activation switch may be any means that indicates an intention indication that the user permits and prohibits the vehicle from traveling, and may not necessarily be manually operated by the user. That is, for example, it may be determined that the activation switch is turned off when the distance between the portable wireless device and the vehicle is equal to or greater than a predetermined distance.

  When an affirmative determination is made in step S10, in step S12, the relays SMR1 and SMR2 are closed and the capacitor 22 is charged while continuing the released state of the clutches C1 and C2 shown in FIG. When charging of the capacitor 22 is completed (step S14: YES), the relay SMR2 is opened and the relay SMR3 is closed, and the process proceeds to step S16. In step S16, the current flowing through motor generator 10 is feedback controlled to command currents idr and iqr to control the torque of motor generator 10 to the required torque Tr. However, at this time, the d-axis command current idr is set to zero. This is a setting for specifying the cause of deviation of the torque actually generated in the motor generator 10 from the required torque Tr to demagnetization of the permanent magnet. That is, since IPMSM is used as the motor generator 10 in the present embodiment, the torque generated in this can include the reluctance torque shown in the second term on the right side of the above formula (c1). Since the reluctance torque is determined according to the d-axis inductance Ld and the q-axis inductance Lq of the motor generator 10, when these values deviate from the values assumed by the control device 30, this is the motor generator. The actual torque of 10 deviates from the required torque Tr. Therefore, the d-axis command current idr is set to zero so that the reluctance torque of the motor generator 10 is zero.

  In the subsequent step S18, the rotational speed ω is acquired. In step S20, torque Tm of motor generator 10 is estimated. Here, the dynamic model shown in the following formula (c2) is used.

Tm = (Jl + Jm) (dω / dt) + Tl (c2)
In the above formula (c2), the inertia moment Jl of the member on the clutch C1, C2 side that rotates together with the rotary shaft 10a when the clutch C1, C2 is released, the inertia moment Jm of the rotary shaft 10a, the oil pump 18, etc. The load Tl applied to the rotating shaft 10a is used.

  In the subsequent step S22, it is determined whether or not the amount by which the estimated torque Tm is lower than the reference torque Ts is larger than the absolute value of the threshold value Tth (<0). This process is for determining the presence or absence of demagnetization. Here, the reference torque Ts may basically be the required torque Tr. However, in view of the fact that the magnetic flux of the permanent magnet of the motor generator 10 changes according to the temperature of the permanent magnet, here, the reference torque Ts is variable according to the temperature TH so as to decrease as the temperature TH of the permanent magnet increases. It is set. The threshold value Tth is set based on an individual difference of the motor generator 10, an allowable range as a secular change, and an estimation error of the torque Tm. That is, it is possible to determine whether or not the actual torque of the motor generator 10 is insufficient at the time of control to the required torque Tr even by subtracting the estimation error of the torque Tm and further subtracting the influence of allowable individual differences and aging. Is set to

  If an affirmative determination is made in step S22, it is determined in step S24 that demagnetization that reduces the magnetic flux of the permanent magnet of motor generator 10 has occurred. In step S26, the fact is notified to the outside (user). Here, for example, a warning lamp that can be visually recognized by the user may be turned on.

  When a negative determination is made in steps S10, S14, and S22 described above, or when the process of step S26 is completed, this series of processes is temporarily terminated.

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

  (1) In feedback control to the command currents idr and iqr performed to control the torque of the motor generator 10 to the required torque Tr, the amount by which the actual torque of the motor generator 10 falls below the reference torque Ts is a threshold Tth (<0 When the absolute value is larger than the absolute value of), it is determined that demagnetization occurs in the motor generator 10. Thereby, the presence or absence of demagnetization can be judged suitably.

  (2) Whether or not the magnetic flux of the permanent magnet of the motor generator 10 has decreased in the state where the clutch C1 is released is determined. As a result, it is only necessary to grasp the actual torque of the motor generator 10 in a state where the load torque is not applied to the rotating shaft 10a of the motor generator 10 from the driving wheel 14 side.

  (3) Whether or not the magnetic flux of the permanent magnet of the motor generator 10 has decreased in a state where the clutch C2 is released is determined. As a result, it is only necessary to grasp the actual torque of the motor generator 10 in a state where no load torque is applied to the rotating shaft 10a of the motor generator 10 from the engine 16 side, and therefore it becomes easy to grasp the actual torque.

  (4) The torque Tm was estimated by a dynamic model. As a result, the torque estimating means can be configured only by acquiring values such as moments of inertia for members mechanically connected to the motor generator 10, so that the construction of the torque estimating means is facilitated.

  (5) The reference torque Ts is variably set according to the temperature TH of the permanent magnet of the motor generator 10. Thereby, the determination precision of the presence or absence of the reduction | decrease of magnetic flux can be improved.

  (6) The presence or absence of demagnetization is determined based on the torque actually generated in the motor generator 10 when the torque of the motor generator 10 is controlled with the relays SMR1 and SMR3 connected. Thereby, since the torque of motor generator 10 can be increased, it is possible to improve the accuracy of determining whether or not there is a decrease in magnetic flux.

(7) The presence or absence of demagnetization is determined based on the torque actually generated in the motor generator 10 when the torque of the motor generator 10 is controlled while setting the d-axis command current idr to zero. As a result, the demagnetization determination process can be performed while setting the reluctance torque to zero, and as a result, the accuracy of determining the presence or absence of demagnetization can be improved.
<Second Embodiment>
Hereinafter, the second embodiment will be described with reference to the drawings with a focus on differences from the first embodiment.

  FIG. 4 shows the motor generator 10 and the power control unit 20 according to the present embodiment and part of the processing performed by the control device 30. In FIG. 4, members and processes corresponding to the processes shown in FIG. 2 are given the same reference numerals for convenience.

  As shown in the figure, in this embodiment, a torque detector 60 that detects the torque of the motor generator 10 is provided, and the presence or absence of demagnetization is determined using the torque detected thereby. Here, the torque detector 60 is adjusted in advance so that an appropriate torque can be detected in a state where the clutches C1 and C2 are released.

  According to this embodiment described above, in addition to the effects (1) to (3) and (5) to (7) of the first embodiment, the following effects can be obtained. Become.

(8) By using the torque detected by the torque detector 60, it is possible to reduce the calculation load of processing for determining the presence or absence of demagnetization.
<Third Embodiment>
Hereinafter, the third embodiment will be described with reference to the drawings with a focus on differences from the first embodiment.

  In the present embodiment, a parameter having a correlation with the actual torque is used instead of estimating the actual torque of the motor generator 10.

  FIG. 5 shows a procedure of processing performed by the demagnetization determination unit 52 according to the present embodiment. This process is repeatedly executed at a predetermined cycle, for example. In FIG. 5, processes corresponding to the processes shown in FIG. 3 are given the same step numbers for convenience.

  As illustrated, in the present embodiment, after the process of step S18, angular acceleration (dω / dt) is calculated as a parameter having a correlation with torque in step S20a. Here, the angular acceleration is a first-order differential value of the rotational speed ω. However, in practice, it may be calculated by a difference calculation of the rotational speed ω.

  In the subsequent step S22a, it is determined whether or not the amount by which the angular acceleration (dω / dt) is lower than the reference acceleration As is greater than the absolute value of the threshold value Ath (<0). This process is for determining the presence or absence of demagnetization using the fact that there is a positive correlation between the two such that the greater the actual torque of the motor generator 10, the greater the angular acceleration. Here, the reference acceleration As is set to a smaller value as the temperature TH of the motor generator 10 is higher.

According to the present embodiment described above, it is possible to obtain an effect according to the first embodiment.
<Fourth Embodiment>
Hereinafter, the fourth embodiment will be described with reference to the drawings with a focus on differences from the first embodiment.

  In the present embodiment, a parameter having a correlation with the actual torque is used instead of estimating the actual torque of the motor generator 10.

  FIG. 6 shows a procedure of processing performed by the demagnetization determination unit 52 according to the present embodiment. This process is repeatedly executed at a predetermined cycle, for example. In FIG. 6, processes corresponding to the processes shown in FIG. 3 are given the same step numbers for convenience.

  As shown in the figure, in the present embodiment, after the torque control is started by the process of step S16, a time measuring operation is started (step S28), and a predetermined time is waited (step S30). Then, when the predetermined time has elapsed (step S30: YES), the rotational speed ω is acquired in step S18, and in step S22b, the amount by which the rotational speed ω falls below the reference speed ωs is greater than the absolute value of the threshold ωth (<0). Judge whether it is large or not. In this process, since there is a positive correlation between the actual torque of the motor generator 10 and the angular acceleration, the presence or absence of demagnetization is determined by utilizing the fact that the rotational speed ω after a predetermined time elapses increases as the torque increases. It is for judging. Here, reference speed ωs is set to a smaller value as temperature TH of motor generator 10 is higher.

  According to this embodiment described above, in addition to the effects (1) to (3) and (5) to (7) of the first embodiment, the following effects can be obtained. Become.

(9) By using the rotational speed ω of the motor generator 10 when a predetermined time has elapsed from the start of torque control, information equivalent to angular acceleration is acquired while avoiding differential calculation processing for calculating angular acceleration. can do.
<Fifth Embodiment>
Hereinafter, a fifth embodiment will be described with reference to the drawings, focusing on differences from the first embodiment.

  In the present embodiment, a parameter having a correlation with the actual torque is used instead of estimating the actual torque of the motor generator 10.

  FIG. 7 shows a procedure of processing performed by the demagnetization determination unit 52 according to the present embodiment. This process is repeatedly executed at a predetermined cycle, for example. In FIG. 7, processes corresponding to the processes shown in FIG. 3 are given the same step numbers for convenience.

  As shown in the figure, in the present embodiment, after the torque control is started by the process of step S16, the time counting operation is started (step S28), and the process waits until the rotational speed ω of the motor generator 10 reaches the specified speed ω0 (step S28). S32). When the specified speed ω0 is reached (step S32: YES), in step S22c, it is determined whether or not the amount of elapsed time from the start of torque control exceeds the reference time is greater than the threshold time (> 0). In this process, since there is a positive correlation between the actual torque and the angular acceleration of the motor generator 10, the time required to reach the specified speed ω0 becomes shorter as the torque becomes larger. It is for judging the presence or absence. Here, the reference time is set to a larger value as temperature TH of motor generator 10 is higher.

  According to this embodiment described above, in addition to the effects (1) to (3) and (5) to (7) of the first embodiment, the following effects can be obtained. Become.

(10) By using the time required from the start of torque control until the rotational speed ω of the motor generator 10 reaches the specified speed ω0, while avoiding differential calculation processing for calculating angular acceleration, etc. Information equivalent to angular acceleration can be acquired.
<Sixth Embodiment>
Hereinafter, the sixth embodiment will be described with reference to the drawings with a focus on differences from the first embodiment.

  In the present embodiment, it is determined that demagnetization has occurred when the rate of decrease in the magnetic flux of the permanent magnet of motor generator 10 is large. This is intended to determine the presence or absence of demagnetization with high accuracy. That is, the demagnetization usually occurs when the control of the motor generator 10 fails. For this reason, the abnormal reduction | decrease which makes it the detection object about the magnetic flux of a permanent magnet will arise abruptly. Here, as exemplified in the first embodiment, when determining the presence or absence of demagnetization based on the comparison with the reference value (reference torque Ts), as described above, the estimation error of the torque Tm and the individual motor generator 10 The reference torque Ts and the threshold value Tth are set so that it can be determined that the magnetic flux has decreased even after subtracting the difference or the influence of aging. However, if the reference torque Ts and the threshold value Tth are set in consideration of the allowable maximum value of the decrease in the magnetic flux of the permanent magnet due to secular change, for example, it is detected by the control failure of the motor generator 10 when the decrease of the magnetic flux due to secular change can be ignored. Even if a decrease in the magnetic flux to occur occurs, there is a concern that the accuracy of detecting this will decrease.

  FIG. 8 shows a procedure of processing performed by the demagnetization determination unit 52 according to the present embodiment. This process is repeatedly executed at a predetermined cycle, for example. In FIG. 8, processes corresponding to the processes shown in FIG. 3 are given the same step numbers for convenience.

  As shown in the drawing, in the present embodiment, after completion of the process of step S20, it is determined in step S22d whether the amount by which the estimated torque Tm is less than the reference torque Ts is greater than a threshold value Tth (<0). To do. If a negative determination is made in step S22d, it is determined that no demagnetization has occurred, so in step S34, the reference torque Ts is set to the torque Tm estimated this time. As a result, in the next step S22d, the reference torque Ts updated in the current step S34 is used.

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

(11) Based on the estimated change rate of the torque Tm, the presence or absence of a decrease in the magnetic flux of the permanent magnet of the motor generator 10 was determined. As a result, it is possible to improve the determination accuracy of the presence or absence of abnormal magnetic flux reduction caused by control failure of the motor generator 10 or the like.
<Seventh Embodiment>
Hereinafter, the seventh embodiment will be described with reference to the drawings with a focus on differences from the first embodiment.

  In this embodiment, before the control device 30 is mounted on the system shown in FIG. 1, the reference torque Ts is set based on the torque Tm estimated at the beginning of mounting without having information on the reference torque Ts. To do.

  FIG. 9 shows a processing procedure regarding the setting of the reference torque Ts according to the present embodiment. This process is repeatedly executed by the control device 30 at a predetermined cycle, for example. In FIG. 9, processes corresponding to the processes shown in FIG. 3 are given the same step numbers for convenience.

  In this series of processing, first, in step S40, it is determined whether or not the reference value acquisition flag is on. This reference value acquisition flag indicates that the reference torque Ts has been acquired when it is on, and indicates that the reference torque Ts has not yet been acquired when it is off. If a negative determination is made in step S40, the processes of steps S10 to S20 shown in FIG. 3 are performed. When the process of step S20 is completed, in step S42, the torque Tm just estimated is set as the reference torque Ts, and the reference value acquisition flag is turned on.

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

(12) The reference torque Ts is set based on the torque Tm estimated when the motor generator 10 is initially used. Thereby, the man-hour required for setting the reference torque Ts can be reduced.
<Other embodiments>
Each of the above embodiments may be modified as follows.

"Torque control means"
The current feedback control means is not limited to that illustrated in FIG. For example, it may further have a feedforward term such as a known non-interference term or an induced voltage compensation term. Moreover, it is not restricted to what performs PWM control, For example, you may perform instantaneous electric current value control and model prediction control.

  The torque control means is not limited to a means for controlling the command currents idr and iqr according to the required torque Tr, but for example, a torque feedback control means for performing feedback control of the torque estimated from the actual currents id and iq to the required torque Tr. There may be. Even in this case, the torque estimator based on the actual currents id and iq estimates the torque on the assumption that the armature linkage flux constant of the permanent magnet is the initial value (before demagnetization). When the magnetism is generated, the actual torque of the motor generator 10 is reduced. For this reason, the presence or absence of demagnetization can be determined by estimating the actual torque. As the torque feedback control means, for example, there is a known technique such as a rectangular wave control means.

  Incidentally, in all of the above-described contents, the electric state quantity of the motor generator 10 as an input parameter of the torque control means becomes a current, but may be a magnetic flux on the stator side. Even in this case, since the assumed value for the magnetic flux of the permanent magnet is premised upon the control to the required torque Tr, it is possible to determine the presence or absence of demagnetization in the above manner.

"Torque estimation means"
The dynamic model is not limited to that exemplified in the first embodiment. For example, when estimating the torque when a member (torque converter or the like) having a damper action is mechanically connected to the motor generator 10 or the like, a model in which a damper term D · ω (D: constant) is added is used. Also good. If the oil pump 18 is not mechanically connected, a model in which the term of the load Tl is deleted may be used. However, the load Tl can be deleted from the dynamic model by reflecting the load Tl on the reference torque Ts. That is, for example, when a value obtained by subtracting the load Tl from the required torque Tr is used as the reference torque Ts or the like, the torque to be compared with this is not the actual torque of the motor generator 10, but the load Tl may be deleted therefrom. Is appropriate.

  The ability to estimate the torque from the dynamic model means that a map can be constructed in which the rotational speed ω and the angular acceleration dω / dt are input parameters and the estimated torque value is an output parameter. For this reason, not only a dynamic model but a map may be provided and a torque estimation means may be comprised. Here, the map is storage means in which the value of the output parameter is stored for each of a plurality of discrete values for the input parameter.

"Load torque acquisition means"
The load torque acquisition means is not limited to the one that performs the process of releasing the mechanical connection between the drive wheels 14 and the engine 16 and the rotating shaft 10a of the motor generator 10. For example, information relating to load torque during traveling of the vehicle, that is, in a state where the drive wheels 14 and the motor generator 10 are mechanically coupled may be acquired. This information includes, for example, the weight of the vehicle, the inclination angle of the traveling road surface, the friction coefficient of the traveling road surface, the surrounding wind speed and direction. That is, it is possible to estimate the load torque applied to the drive wheels 14 based on these pieces of information, and thus it is possible to estimate the load torque applied to the rotating shaft 10a of the motor generator 10. Further, for example, load torque information when the clutch C2 is in the engaged state may be acquired. This can be realized, for example, by providing means for storing information relating to the average value of the load torque accompanying the rotation of the crankshaft when the combustion control of the engine 16 is stopped.

"Drive wheel side blocking means"
The drive wheel side blocking means is not limited to a wet electronically controlled clutch, and may be a dry electronically controlled clutch, for example.

"Engine side blocking means"
The engine side shut-off means is not limited to a dry electronically controlled clutch, and may be a wet electronically controlled clutch, for example. Moreover, it is not restricted to the fastening means which can control a pair of rotating shaft to a fastening state and a cancellation | release state by electronic control. For example, a one-way transmission mechanism such as a one-way clutch or a one-way bearing that transmits power as long as the rotation speed on the output side does not become larger than the rotation speed on the input side may be used. When this one-way transmission mechanism is applied to the system shown in FIG. 1, the motor generator 10 side may be the output side.

"Setting method"
In the first to fifth embodiments, the reference value may be a fixed value without being variably set according to the temperature. However, in this case, it is desirable to provide a sufficient margin for the condition for determining demagnetization. This margin setting method can be performed, for example, by adjusting the setting value of the threshold value Tth or by setting the reference torque Ts itself at a high temperature as regards the processing in step S22 of FIG. .

  In the sixth embodiment, the reference torque Ts and the threshold value Tth may be variable according to the temperature.

  Further, in the seventh embodiment, after the reference torque Ts is acquired, this is corrected and used according to the temperature difference of the motor generator 10 at the time of demagnetization determination processing and at the time of acquisition of the reference torque Ts. Also good.

  Note that the reference value can include an amount related to the load torque such as the load Tl as described in the section “Regarding the torque estimation means”.

  For example, if the second term on the left side of step S22 in FIG. 3 is moved to the right side, “Tm <Ts + Tth” is obtained, which is equivalent to determining whether the torque Tm is smaller than the determination value (Ts + Tth). Become. For this reason, the reference value and the threshold value may be unified as the determination value, and the subtraction process between the torque Tm and the reference torque Ts may not be actually performed.

"Demagnetization judgment based on actual torque parameter change rate"
As in the sixth embodiment, the reference torque Ts is not necessarily updated by the torque Tm estimated each time. For example, the reference torque Ts is updated every time the vehicle starts a predetermined number of times. May be.

  Further, not only the reference value (reference torque Ts) is updated, but the estimated torque Tm for each time is stored, and the absolute value of the difference between the estimated torque Tm between the current time and the previous time is the estimated torque Tm of the past two times. The demagnetization may be determined when the absolute value of the difference is a specified number (> 2) times or more.

  The parameter for which the change speed is to be quantified is not limited to the estimated torque Tm, and may be, for example, angular acceleration.

“Requested torque Tr”
In each of the above embodiments, the presence / absence of demagnetization is determined during the power running operation of the motor generator 10 by making the required torque Tr larger than zero. However, the present invention is not limited to this. For example, the presence or absence of demagnetization may be determined during the regenerative operation of the motor generator 10 by making the required torque Tr negative. This can be performed, for example, when the start switch is turned off in the system shown in FIG. That is, in the case of the system shown in FIG. 1, the motor generator 10 is in a state where the clutches C1 and C2 are released to supply oil to the clutches C1 and C2 and the transmission 12 even when the drive wheels 14 are stopped. Is driven. For this reason, since the motor generator 10 is rotating immediately after the start switch is turned off, whether or not demagnetization is determined based on the estimation of the torque Tm (<0) or the like when the regeneration is controlled. Good. However, even if it is not such a system, if the driving wheel side blocking means for blocking the transmission of power to and from the driving wheel 14 is provided, the motor generator 10 is power-running immediately after the start switch is turned off or immediately after being turned on. The presence or absence of demagnetization can also be determined based on a parameter relating to torque during regenerative operation.

  Incidentally, if the regenerative operation is used, the absolute value of the torque can be increased even if the relays SMR1 to SMR3 are open.

"Execution conditions for determining whether or not demagnetization is present"
What is not limited to immediately after the start switch is turned on is as described in the column “About load torque acquisition means” and “About required torque Tr”.

About the system
The parallel hybrid system is not limited to the one illustrated in FIG. 1, but may be, for example, that illustrated in FIG. In FIG. 10, members corresponding to those shown in FIG. 1 are given the same reference numerals for convenience. In FIG. 10, transmissions 12a and 12b are provided in parallel, and a so-called dual clutch transmission (DCT) in which each of them and a rotating shaft 10a of the motor generator 10 are engaged and released by clutches C1a and C1b, respectively. ). In this case, it is desirable to perform the demagnetization determination process by setting both clutches C1a and C1b to the released state.

  The hybrid system is not limited to a parallel hybrid system, and may be a series hybrid system or a parallel series hybrid system, for example.

  Further, the present invention is not limited to a hybrid system, and may be an electric vehicle or the like that includes only a rotating machine as an in-vehicle main unit without including an internal combustion engine.

  In any case, it is desirable to perform the demagnetization determination process in a state where the drive wheel side blocking means is provided and the transmission of power between the drive wheel and the rotating machine is blocked. Further, in a parallel series hybrid system or the like, it is desirable to perform demagnetization determination processing in a state in which engine-side cutoff means is provided and power transmission between the internal combustion engine and the rotating machine is cut off.

"others"
-The rotating machine having saliency is not limited to a salient pole machine, and may be, for example, a reverse salient pole machine. Moreover, as a rotary machine provided with a permanent magnet, it is not restricted to what has a saliency, For example, a surface magnet synchronous machine (SPM) etc. may be sufficient.

  -The command current for the demagnetization determination process is not limited to that at which the d-axis current becomes zero. For example, when targeting SPM or the like, it is considered that a decrease in demagnetization determination accuracy caused by flowing a d-axis current is unlikely to occur as compared with IPMSM. However, the absolute value of the d-axis current may be larger than zero even when a rotating machine having saliency such as IPMSM is targeted.

  The power supply source is not limited to the high voltage battery 24 (secondary battery) but may be a fuel cell.

  DESCRIPTION OF SYMBOLS 10 ... Motor generator, 52 ... Demagnetization judgment part, IV ... Inverter.

Claims (18)

In a control device for a rotating machine that controls a control amount of a rotating machine including a permanent magnet,
Torque control means for controlling the torque of the rotating machine to a command value having an absolute value greater than zero;
Load torque acquisition means for acquiring information on load torque applied to the rotating machine;
Demagnetization determination means for determining whether or not there is a decrease in the magnetic flux of the permanent magnet based on a parameter relating to the actual torque of the rotating machine at the time of control by the torque control means. A control device for a rotating machine comprising: The rotating machine is an in-vehicle main machine,
Drive wheel side blocking means for blocking power transmission between the rotating machine and the drive wheel,
The load torque acquisition means is a load torque applied to the rotating machine from the driving wheel side by operating the driving wheel side blocking means to cut off transmission of power between the rotating machine and the driving wheel. To get information that is zero,
The demagnetization determining unit is configured to reduce the magnetic flux of the permanent magnet based on a parameter relating to the actual torque in a state where transmission of power between the rotating machine and the driving wheel is blocked by the driving wheel side blocking unit. The control device for a rotating machine according to claim 1, wherein presence or absence is determined. The vehicle on which the control device is mounted includes an internal combustion engine as an in-vehicle main machine in addition to the rotating machine, and includes an engine-side blocking unit that blocks transmission of power between the rotating machine and the internal combustion engine.
The load torque acquisition means operates the engine side shut-off means to shut off transmission of power between the rotating machine and the internal combustion engine, so that load torque applied to the rotating machine from the internal combustion engine side is obtained. To obtain information that it is zero,
The demagnetization determining means is the presence or absence of a decrease in the magnetic flux of the permanent magnet based on the parameter relating to the actual torque in a state where the transmission of power between the rotating machine and the internal combustion engine is interrupted by the engine side interruption means. The control device for a rotating machine according to claim 2, wherein:   The control device for a rotating machine according to any one of claims 1 to 3, wherein the parameter relating to the actual torque of the rotating machine is a value of the torque of the rotating machine. Torque estimation means for estimating the torque of the rotating machine as input with information on the change in the rotation angle of the rotating machine;
5. The control apparatus for a rotating machine according to claim 4, wherein the demagnetization determining means uses the torque estimated by the torque estimating means as a parameter relating to an actual torque of the rotating machine.   6. The dynamic estimation model according to claim 5, wherein the torque estimation means is a dynamic model having a term obtained by multiplying a rotation axis of the rotating machine and an inertia moment of a rotating body rotating in conjunction with the rotation acceleration of the rotating machine. The control apparatus of the described rotating machine.   5. The control device for a rotating machine according to claim 4, wherein the parameter relating to the actual torque of the rotating machine is an output of a torque detector that detects the torque of the rotating machine.   The control device for a rotating machine according to any one of claims 1 to 3, wherein the parameter relating to the actual torque of the rotating machine is related to a changing speed of the rotating speed of the rotating machine.   The control device for a rotating machine according to claim 8, wherein the parameter relating to the actual torque of the rotating machine is an angular acceleration of the rotating machine.   9. The control of the rotating machine according to claim 8, wherein the parameter relating to the actual torque of the rotating machine is a rotational speed of the rotating machine when a predetermined time has elapsed from the start of the torque control by the torque control means. apparatus.   9. The parameter relating to the actual torque of the rotating machine is a time required for the rotational speed of the rotating machine to reach a specified speed after the start of the torque control by the torque control means. Rotating machine control device.   12. The parameter relating to the actual torque of the rotating machine uses the output of the rotation angle detector of the rotating machine or the output of the rotation angle estimator. The control device for a rotating machine according to Item 1. For the parameter relating to the torque, further comprising setting means for setting a determination value according to a torque command value for the rotating machine,
The demagnetization determining means determines whether or not there is a decrease in the magnetic flux of the permanent magnet, based on a comparison between the parameter regarding the actual torque and the determination value. The control apparatus of the rotary machine as described in the paragraph.   The setting unit variably sets the determination value used by the demagnetization determination unit according to the temperature of the rotating machine when the parameter regarding the actual torque used for the determination by the demagnetization determination unit is acquired. The rotating machine control device according to claim 13.   The said setting means sets the said judgment value based on the parameter regarding the said actual torque at the time of control by the said torque control means at the time of the initial use of the said rotary machine. Rotating machine control device.   13. The rotating machine according to claim 1, wherein the demagnetization determining unit determines a decrease in magnetic flux of the permanent magnet based on a change speed of a parameter related to the actual torque. Control device. The rotating machine is an in-vehicle main machine,
The rotating machine receives power from a power supply source via a power conversion circuit,
A relay is connected between the power conversion circuit and the power supply source,
The demagnetization determining means determines whether or not there is a decrease in the magnetic flux of the permanent magnet based on a parameter relating to the actual torque when the torque is controlled by the torque control means with the relay connected. The control device for a rotating machine according to claim 1, wherein the control device is a rotary machine. The rotating machine has saliency,
The torque control means controls the torque of the rotating machine to the command value by controlling the current of the rotating machine to a command value, and the command value of the current is a current value in the d-axis direction. The control device for a rotating machine according to any one of claims 1 to 17, characterized in that is zero.

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