Motor control device

Abstract

A motor control device (40) controls driving of a motor (10) having a motor winding (11), and includes an angle calculation section (51), a drive control section (53), and an abnormality diagnosis section (58). The angle calculation section (51) acquires a detection value from a rotation angle sensor (13) that detects a rotation angle of the motor (10), and calculates a motor rotation angle. The drive control section (53) controls driving of the motor (10) based on the motor rotation angle. The abnormality diagnosis section (58) performs abnormality diagnosis of an energization system while maintaining an energization state, in a case where an abnormality of the motor rotation angle is detected during driving of the motor (10).

Description

[0001] Cross-references to related applications

[0002] This application is based on Japanese Patent Application No. 2020-008475, filed on January 22, 2020, the contents of which are incorporated herein by reference. Technical Field

[0003] This disclosure relates to motor control devices. Background Technology

[0004] Currently, gear shifting devices that switch gears by controlling the drive of an actuator are known. For example, in Patent Document 1, a disconnection diagnosis is performed by performing an initial check before shifting the gear.

[0005] Existing technical documents

[0006] Patent documents

[0007] Patent Document 1: Japanese Patent Application Publication No. 2019-71726 Summary of the Invention

[0008] In Patent Document 1, faults such as the disconnection of switching elements, which cannot be detected without power, occur when the motor is not driven. Therefore, even if the fault has been recovered from temporarily, it cannot be diagnosed. The object of this disclosure is to provide a motor control device capable of appropriately detecting abnormalities.

[0009] The motor control device disclosed herein controls the drive of a motor having motor windings and includes an angle calculation unit, a drive control unit, and an anomaly diagnosis unit. The angle calculation unit acquires a detection value from a rotation angle sensor that detects the motor's rotation angle and calculates the motor's rotation angle. The drive control unit controls the motor's drive based on the motor's rotation angle. If an anomaly in the motor's rotation angle is detected during motor drive, the anomaly diagnosis unit performs an anomaly diagnosis of the power supply system while maintaining the energized state. Therefore, it is possible to appropriately distinguish whether the anomaly in the motor's rotation angle during motor drive is caused by an anomaly in the rotation angle sensor or by an anomaly in the power supply system. Attached Figure Description

[0010] The foregoing and other objects, features, and advantages of this disclosure will become more apparent from the accompanying drawings and from the detailed description below. The drawings are as follows:

[0011] Figure 1 This is a perspective view showing the shift-by-wire system of the first embodiment;

[0012] Figure 2 This is a schematic structural diagram of the shift-by-wire system according to the first embodiment;

[0013] Figure 3 This is a circuit diagram illustrating the ECU of the first embodiment;

[0014] Figure 4 This is a flowchart illustrating the anomaly detection process of the first embodiment;

[0015] Figure 5 This is a flowchart illustrating the drive mode selection process of the first embodiment;

[0016] Figure 6 This is a timing diagram illustrating the motor drive control of the first embodiment;

[0017] Figure 7 This is a timing diagram illustrating the motor drive control of the first embodiment;

[0018] Figure 8 This is a flowchart illustrating the drive mode selection process of the second embodiment;

[0019] Figure 9 This is a timing diagram illustrating the motor drive control of the second embodiment. Detailed Implementation

[0020] <First Implementation Method>

[0021] The motor control device will now be described based on the accompanying drawings. In several embodiments, the same reference numerals will be used to denote substantially the same structures, and descriptions will be omitted. Figures 1 to 7 This refers to the motor control device of the first embodiment. For example... Figure 1 and Figure 2 As shown, the drive-by-wire shift system 1 includes a motor 10, a shift gear switching mechanism 20, a parking lock mechanism 30, and an ECU 40 as a motor control device.

[0022] The motor 10 is powered by a battery (not shown) installed in the vehicle, and functions as a drive source for the gear shifting mechanism 20. In this embodiment, the motor 10 is a switched reluctance motor, having a motor winding 11 wound around a stator (not shown). The motor winding 11 has a U-phase winding 111, a V-phase winding 112, and a W-phase winding 113, which are connected together via a terminal block 115 (see reference). Figure 3 ).

[0023] like Figure 2 As shown, encoder 13, acting as a rotation angle sensor, detects the rotational position of the rotor (not shown) of motor 10. Encoder 13 is, for example, a magnetic rotary encoder, consisting of a magnet that rotates integrally with the rotor and a Hall IC for magnetic detection. Encoder 13 outputs pulse signals, i.e., encoder signals, at predetermined angles in sync with the rotation of the rotor.

[0024] The speed reducer 14 is disposed between the motor shaft and the output shaft 15 of the motor 10, reducing the rotation speed of the motor 10 and outputting the speed reduction to the output shaft 15. Thus, the rotation speed of the motor 10 is transmitted to the gear shifting mechanism 20. An output shaft sensor 16 is disposed on the output shaft 15 to detect the angle of the output shaft 15. The output shaft sensor 16 is, for example, a potentiometer.

[0025] like Figure 1 As shown, the gear shifting mechanism 20 has a stop plate 21, a stop spring 25 and a stop roller 26, etc., which transmit the rotational driving force output from the reducer 14 to the manual valve 28 and the parking locking mechanism 30.

[0026] A stop plate 21 is fixed to the output shaft 15 and driven by a motor 10. A pin 24 protruding parallel to the output shaft 15 is provided on the stop plate 21. The pin 24 is connected to a manual valve 28. The manual valve 28 reciprocates axially by driving the stop plate 21 with the motor 10. That is, the gear shifting mechanism 20 converts the rotational motion of the motor 10 into linear motion and transmits it to the manual valve 28. The manual valve 28 is located on the valve body 29. By causing the manual valve 28 to reciprocate axially, the hydraulic supply path connected to a hydraulic clutch (not shown) is switched, and the gear position is changed by switching the engagement state of the hydraulic clutch.

[0027] On the side of the stop spring 25 of the stop plate 21, four valleys 22 are formed corresponding to the gear positions P (parking), R (reverse), N (neutral), and D (drive).

[0028] The stop spring 25 is an elastically deformable plate-shaped component with a stop roller 26 at its front end. The stop spring 25 applies force to the stop roller 26 towards the rotation center of the stop plate 21. If a rotational force greater than a specified magnitude is applied to the stop plate 21, the stop spring 25 elastically deforms, and the stop roller 26 moves between the valleys 22. By engaging the stop roller 26 in either of the valleys 22, the swing of the stop plate 21 is restricted, the axial position of the manual valve 28 and the state of the parking lock mechanism 30 are determined, and the shift gear of the automatic transmission 5 is fixed.

[0029] The parking locking mechanism 30 includes a parking lever 31, a cone 32, a parking locking pawl 33, a shaft 34, and a parking gear 35. The parking lever 31 is generally L-shaped, with one end 311 fixed to the stop plate 21. A cone 32 is provided at the other end 312 of the parking lever 31. The cone 32 is formed such that its diameter decreases as it approaches the other end 312.

[0030] The parking lock pawl 33 abuts against the conical surface of the cone 32 and is configured to swing about the shaft 34. A protrusion 331 is provided on the parking gear 35 side of the parking lock pawl 33, capable of engaging with the parking gear 35. If the cone 32 moves in the P direction due to the rotation of the stop plate 21, the parking lock pawl 33 is pushed upwards, and the protrusion 331 engages with the parking gear 35. Conversely, if the cone 32 moves in a direction other than P, the engagement between the protrusion 331 and the parking gear 35 is disengaged.

[0031] The parking gear 35 is mounted on an axle (not shown) and is configured to engage with the protrusion 331 of the parking lock pawl 33. When the parking gear 35 engages with the protrusion 331, rotation of the axle is restricted. When the gear is in a position other than P (Park), the parking gear 35 is not locked by the parking lock pawl 33, and rotation of the axle is not hindered by the parking lock mechanism 30. However, when the gear is in P, the parking gear 35 is locked by the parking lock pawl 33, and rotation of the axle is restricted.

[0032] like Figure 2 and Figure 3 As shown, the ECU40 includes a drive circuit 41, a voltage detection unit 43, a current detection unit 45, and a control unit 50. Figure 2 The description of the voltage detection unit 43 and the current detection unit 45 is omitted. For example... Figure 3 As shown, the drive circuit 41 has three switching elements 411 to 413 to switch the energization of windings 111 to 113. In this embodiment, the switching elements 411 to 413 are MOSFETs, which are disposed between the windings 111 to 113 of each phase and the ground wire.

[0033] The windings 111 to 113 of the motor winding 11 are connected together via a terminal 115. Power is supplied from the battery to the terminal 115 via a power line. A relay section 46 (see reference) is provided on the power line. Figure 2 When the relay section 46 is turned on, it supplies power to the wiring section 115.

[0034] The voltage detection unit 43 includes a U-phase terminal voltage detection unit 431, a V-phase terminal voltage detection unit 432, and a W-phase terminal voltage detection unit 433. The U-phase terminal voltage detection unit 431 detects the U-phase terminal voltage Vu, the V-phase terminal voltage detection unit 432 detects the V-phase terminal voltage Vv, and the W-phase terminal voltage detection unit 433 detects the W-phase terminal voltage Vw. The current detection unit 45 detects the current energized to the motor winding 11. In this embodiment, the current detection unit 45 is a shunt resistor.

[0035] The control unit 50 is mainly composed of a microcomputer or the like, and internally includes a CPU, ROM, RAM, I / O, and bus lines connecting these structures (not shown). The processing in the control unit 50 can be either software processing, which is implemented by the CPU executing programs pre-stored in a physical storage device such as ROM (i.e., reading non-temporary tangible recording media), or hardware processing, which is implemented by dedicated electronic circuits.

[0036] The control unit 50 includes an angle calculation unit 51, a target angle setting unit 52, a drive control unit 53, a voltage acquisition unit 56, a current acquisition unit 57, and an abnormality diagnosis unit 58. The angle calculation unit 51 counts the pulse edges of each phase of the encoder signal output from the encoder 13 and calculates the encoder count value θen. The encoder count value θen is a value corresponding to the rotational position of the motor 10 and corresponds to the "motor angle".

[0037] The target angle setting unit 52 sets a target count value θcmd, which is the target position that stops the motor 10. When switching gears, the target count value θcmd is set to cause the stop roller 26 to engage with the valley 22 corresponding to the target gear.

[0038] The drive control unit 53 controls the drive of the motor 10 to change the encoder count value θen to the target count value θcmd. Specifically, the drive control unit 53 controls the on / off operation of the switching elements 411 to 413 by generating phase indications and outputting them to the drive circuit 41.

[0039] The voltage acquisition unit 56 acquires the terminal voltages Vu, Vv, and Vw from the voltage detection unit 43. The current acquisition unit 57 acquires the voltage on the drive circuit 41 side of the current detection unit 45 as a detection value related to the motor current Im.

[0040] In this embodiment, switching elements 411-413 are located on the ground side of windings 111-113. Therefore, the U-phase terminal voltage Vu is the battery voltage Vb when switching element 411 is open, and the ground potential Vg when switching element 411 is closed. The same applies to the V-phase and W-phase; the terminal voltages Vv and Vw are the battery voltage Vb when switching elements 412 and 413 are open, and the ground potential Vg when they are closed. Hereinafter, it is assumed that the ground potential Vg is 0.

[0041] The fault diagnosis unit 58 diagnoses faults in the shift-by-wire system 1. Faults in the shift-by-wire system 1 include faults in the encoder 13 (i.e., encoder malfunction) and faults in the power supply system. In this embodiment, as a fault in the power supply system, a non-conducting fault caused by an open-circuit fault in the switching elements 411-413 will be described. Furthermore, non-conducting faults are not limited to faults in the switching elements 411-413 themselves, but also include signal faults, battery short circuits in the windings 111-113 of each phase, etc. Hereinafter, the fault determination of phase U will be the focus of the explanation.

[0042] However, for anomalies like the inability to conduct, which cannot be detected without power, the anomaly cannot be detected in real time when the drive motor 10 is not needed. Therefore, incorrect judgments may be made regarding situations where the system temporarily returns to normal. In addition, if the encoder count value θen stagnates during gear shifting, it cannot be determined whether the anomaly is due to an encoder 13 malfunction or an inability to conduct, and therefore it cannot be determined whether gear shifting can proceed.

[0043] Therefore, in this embodiment, if the encoder count value θen stagnates during gear shifting, it is determined whether the problem is due to an encoder malfunction or a failure to conduct. Specifically, if the power-on indicator phase is phase U when the encoder count value θen stagnates, and the voltage Vu at the U-phase terminal is 0, then the power-on system is normal, and the problem is determined to be an encoder malfunction. In this case, since the power-on system is normal, the encoder count value θen is not used; instead, the motor 10 is driven by switching the open-circuit drive of the power-on phase at predetermined intervals to continue gear shifting.

[0044] Furthermore, if the energized phase is phase U when the encoder count value θen stops, and if the voltage Vu at the U-phase terminal is equal to the battery voltage Vb, it is determined that phase U is not conducting properly, and the power supply to motor 10 is disconnected. By disconnecting the power supply to motor 10, the stop roller 26 falls into the nearest valley 22 due to the load torque. The following explanation uses the cases where the faulty phase is phase U and the normal phases are phases V and W as examples.

[0045] based on Figure 4 The flowchart below illustrates the anomaly detection processing of this embodiment. When the drive mode is feedback mode, the anomaly diagnosis unit 58 performs this processing at a predetermined cycle (e.g., 1 [ms]). Hereinafter, the "step" in step S501 will be omitted and simply labeled as the symbol "S". The other steps are the same.

[0046] In S501, the anomaly diagnosis unit 58 determines whether the encoder 13 is stopped. Here, if the encoder count value θen does not change within the determination time or determination number, it is determined that the encoder 13 is stopped. If it is determined that the encoder 13 is not stopped (S501: No), the processing after S502 is skipped. If it is determined that the encoder 13 is stopped (S501: Yes), the process proceeds to S502.

[0047] In S502, the abnormality diagnosis unit 58 determines whether the terminal voltage V# of the energized indicator phase is above the voltage determination threshold Vth. If the energized indicator phase is phase U, then the terminal voltage V# is the U-phase terminal voltage Vu. In this case, "#" refers to the energized indicator phase. Similar to S501, if the state of the terminal voltage V# of the energized indicator phase being above the voltage determination threshold Vth continues for a determination time or a determination number of times, a positive determination is made. The determination time and determination number can be the same as or different from those in S501.

[0048] The voltage judgment threshold Vth is a value between the ground potential Vg and the battery voltage Vb, set to any value capable of distinguishing between a non-conducting abnormality and an encoder abnormality. If the terminal voltage V# of the energizing indicator phase is determined to be above the voltage judgment threshold Vth (S502: Yes), proceed to S503 to determine a non-conducting abnormality in the energizing indicator phase. If the terminal voltage V# of the energizing indicator phase is determined to be below the voltage judgment threshold Vth (S502: No), proceed to S504 to determine an encoder abnormality.

[0049] based on Figure 5 The flowchart below explains the drive mode selection process of this embodiment. When the vehicle's start switch, such as the ignition switch, is turned on, the control unit 50 performs this process at a predetermined interval (e.g., 1 ms). The failure modes in this embodiment include a "failure (power off) mode" that cuts off the power supply, a "failure (open circuit) mode" that drives the motor 10 by open circuit drive, and a "failure (stop) mode" that stops the motor 10.

[0050] In S101, the control unit 50 determines the current drive mode. If the drive mode is standby mode, it proceeds to S102; if the drive mode is feedback mode, it proceeds to S104; if the drive mode is stop mode, it proceeds to S110; if the drive mode is failure (open circuit) mode, it proceeds to S112; and if the drive mode is failure (stop) mode, it proceeds to S114. Furthermore, if the drive mode is failure (power-off) mode, the processing after S102 is skipped.

[0051] In step S102, when the drive mode is in standby mode, the control unit 50 determines whether the target shift gear has changed. If it determines that the target shift gear has not changed (S102: No), it continues in standby mode. If it determines that the target shift gear has changed (S102: Yes), it enters step S103 and switches the drive mode to feedback mode. In feedback mode, the drive of the motor 10 is controlled by feedback to change the encoder count value θen to the target count value θcmd. In the figure, the feedback is appropriately recorded as "F / B".

[0052] In S104, when the drive mode is in feedback mode, the control unit 50 determines whether the encoder is malfunctioning. If the encoder is malfunctioning (S104: Yes), the control unit proceeds to S105 and switches the drive mode to failure (open circuit) mode. If the encoder is not malfunctioning (S104: No), the control unit proceeds to S106.

[0053] In S106, the control unit 50 determines whether the malfunction is due to a non-conductivity issue in the energizing indicator phase. If the malfunction is confirmed (S106: Yes), the process proceeds to S107, disabling the drive mode (power off) and disconnecting power to the motor 10. If the malfunction is not confirmed (S106: No), the process proceeds to S108.

[0054] In S108, the control unit 50 determines whether the motor 10 has reached the target angle. Here, if the encoder count value θen is within a specified range including the target count value θcmd (e.g., ±2 counts), it is determined that the motor 10 has reached the target angle. If it is determined that the motor 10 has not reached the target angle (S108: No), the feedback mode continues. If it is determined that the motor 10 has reached the target angle (S108: Yes), the process proceeds to S109, switching the drive mode to a stop mode. In the stop mode, the motor 10 is stopped by energizing the two fixed phases corresponding to the encoder count value θen.

[0055] In S110, when the drive mode is in stop mode, the control unit 50 determines whether the fixed phase has been energized. If the fixed phase energization time is longer than a predetermined time, it is determined that the fixed phase energization has been completed. The predetermined time for continuous fixed phase energization is set based on the time required to stop the motor 10. If it is determined that the fixed phase energization has not been completed (S110: No), the stop mode continues. If it is determined that the fixed phase energization has been completed (S110: Yes), the system enters S111 and switches the drive mode to standby mode.

[0056] In S112, when the drive mode is in fail (open circuit) mode, the control unit 50 determines whether the motor 10 has reached the target angle. In fail (open circuit) mode, the encoder count value θen cannot be used; therefore, the number of switching of energized phases is counted to determine this. If it is determined that the motor 10 has not reached the target angle (S112: No), the fail (open circuit) mode continues. If it is determined that the motor 10 has reached the target angle (S112: Yes), the system enters S113 and switches the drive mode to fail (stop) mode. In fail (stop) mode, the motor 10 is stopped by energizing the two stationary phases.

[0057] In S114, when the drive mode is in fail (stop) mode, the control unit 50, similar to S110, determines whether the fixed phase has been energized. If it is determined that the fixed phase has not been energized (S114: No), the fail (stop) mode continues. If it is determined that the fixed phase has been energized (S114: Yes), the system enters S115, switches the drive mode to fail (power off), and cuts off the power supply to the motor 10.

[0058] based on Figure 6 and Figure 7 The timing diagram illustrates the motor drive control of this embodiment. Figure 6 and Figure 7 In the diagram, starting from the top, the information is sequentially displayed as follows: drive mode, motor angle, power-on indication for each phase, terminal voltage for each phase, encoder malfunction status, and non-conducting malfunction status. For the motor angle, the corresponding shift gear is indicated by parentheses. (More details later.) Figure 9 It is the same.

[0059] based on Figure 6 The following describes the situations that caused encoder errors. For example... Figure 6 As shown, at time x10, if the target gear shift changes from P to R, the drive mode switches from standby mode to feedback mode. Furthermore, a target count value θcmd is set so that the stop roller 26 engages with the valley 22 corresponding to the R gear, and the motor 10 is driven by feedback control to change the encoder count value θen to the target count value θcmd. Specifically, the energized phase is switched by changing the energization indication according to the encoder count value θen. In this embodiment, under normal conditions, the terminal voltage of the phase with the energization indication on is 0, and the terminal voltage of the phase with the energization indication off is the battery voltage Vb.

[0060] At time x11, the encoder count θen stops. At this time, the energizing phase is phase U, and the voltage Vu at the U-phase terminal is 0. The motor current Im ≠ 0, and current flows through the motor winding 11. That is, no abnormality has occurred in the energizing system. Therefore, at time x12, after a determination time Xa has elapsed since the encoder count θen stopped, it is determined that the encoder is malfunctioning. Here, the determination of encoder 13 stopping and the determination of energizing status are made simultaneously. However, for example, encoder stopping could be determined at the first determination time, and energizing status could be determined at the second determination time.

[0061] If an encoder malfunction is detected at time x12, the drive mode is set to failure (open circuit) mode, and motor 10 is driven via open circuit drive to continue gear switching. At time x13, if it is determined based on the number of switching of the energized phase that motor 10 has reached the target angle, the drive mode is switched to failure (stop) mode, and motor 10 is stopped by energizing the fixed phase. Figure 6 In the example, phases U and V are energized. At moment x14, when the energization of the fixed phase is completed, the drive mode is set to failure (energization cut-off) mode, and the energization to motor 10 is stopped.

[0062] based on Figure 7 The following explains the situation where the U phase fails to conduct. Figure 7 The processing from time x20 to time x21 in the middle and Figure 6 The processing from time x10 to time x11 is the same. At time x21, the encoder count value θen stops, the energized indicator phase is phase U, but the voltage Vu at the U-phase terminal is the battery voltage Vb, the motor current Im = 0, and no current flows in the motor winding 11. That is, it can be detected that the U-phase winding 111 has a non-conducting abnormality and cannot be energized.

[0063] At time x22, after the determination time Xa has elapsed from time x21, it is determined that there is a failure to conduct, and the drive mode is switched to failure (power off) mode. If the power supply to motor 10 is stopped, motor 10 reverses due to the load torque, and at time x23, stop roller 26 returns to the valley 22 corresponding to P gear.

[0064] In this embodiment, when an encoder stalls, the energized state is maintained, and the voltage at the terminal of the energized indicator phase is used to distinguish in real time whether the problem is an encoder malfunction or a failure to conduct. Therefore, if the encoder is malfunctioning, an open-circuit drive is performed; if the failure to conduct is not occurring, the energized state is cut off. In this case, appropriate measures can be taken in accordance with the specific malfunction.

[0065] As explained above, the ECU 40 of this embodiment controls the drive of the motor 10 having the motor winding 11, and includes an angle calculation unit 51, a drive control unit 53, and an anomaly diagnosis unit 58. The angle calculation unit 51 obtains the detected value from the encoder 13 that detects the rotation angle of the motor 10, and calculates the encoder count value θen. The drive control unit 53 controls the drive of the motor 10 based on the encoder count value θen. If the anomaly of the encoder count value θen is detected during the drive of the motor 10, the anomaly diagnosis unit 58 performs an anomaly diagnosis of the power supply system while maintaining the power-on state.

[0066] Therefore, it is possible to appropriately distinguish whether the abnormal encoder count value θen generated during motor drive is due to an encoder 13 malfunction or a power supply system malfunction. Furthermore, appropriate subsequent control can be implemented based on the abnormal state. For example, when applied to the drive-by-wire system 1, compared to determining the abnormality after gear shifting is completed, abnormality diagnosis can be performed more quickly.

[0067] The anomaly diagnosis unit 58 determines, based on the terminal voltages Vu, Vv, and Vw of the motor winding 11, whether the detected abnormal encoder count value θen is caused by an abnormality in the encoder 13 or by an abnormality in the power supply system. Thus, the anomaly can be appropriately identified.

[0068] If the abnormality of the encoder count value θen is caused by a malfunction in encoder 13, the drive control unit 53 switches to control without using the encoder count value θen and continues to drive the motor 10. Therefore, if the power supply system is normal, the motor 10 can continue to be driven without using the encoder count value θen. Furthermore, in the online gear shifting system 1, gear switching can be performed appropriately.

[0069] If the abnormal encoder count value θen is caused by a power supply system malfunction, the drive control unit 53 cuts off the power supply to the motor 10. This allows for a rapid halt to the drive of the motor 10. Furthermore, in the wired shifting system 1, the system can return to the gear position before the malfunction occurred by applying load torque.

[0070] When an abnormality is detected in the encoder count value θen, if the terminal voltage of the phase indicating power supply (i.e., the power-on indicator phase) is different from the normal value, the abnormality in the encoder count value θen is caused by an abnormality in the power supply system. The abnormality diagnosis unit 58 identifies the power-on indicator phase as the faulty phase. Thus, the abnormal location can be appropriately determined.

[0071] <Second Implementation Method>

[0072] Figure 8 and Figure 9This represents the second implementation method. In this implementation method, if a non-conduction anomaly is determined, the motor 10 is driven by using the remaining two phases of the two-phase drive to switch gears. In addition to the failure modes described in the above implementation methods, this implementation method also includes a failure (two-phase drive) mode.

[0073] based on Figure 8 The flowchart below explains the drive mode selection process of this embodiment. In S201, the control unit 50 determines the drive mode. If the drive mode is standby mode, it proceeds to S201; if the drive mode is feedback mode, it proceeds to S204; if the drive mode is stop mode, it proceeds to S210; if the drive mode is failure (open circuit) mode or failure (two-phase drive) mode, it proceeds to S212; and if the drive mode is failure stop mode, it proceeds to S214. Furthermore, if the drive mode is failure (power-off) mode, the processing after S202 is skipped.

[0074] The processing of S202~S206 and Figure 5 The processing of S102 to S106 is the same. If it is determined by S206 that there is a failure to conduct (S206: Yes), proceed to S207 and switch the drive mode to failure (two-phase drive). For example, if a failure to conduct occurs in phase U, drive motor 10 by using the feedback control of the normal phases V and W to switch the shift gear.

[0075] The processing of S208~S211 and Figure 5 The processing in S108 to S111 is the same. In S212, which is entered when the drive mode is in failure (open circuit) or failure (two-phase drive) mode, the control unit 50 determines whether the motor 10 has reached the target angle. In the case of two-phase drive, the encoder 13 is normal, so, as in S108, the determination can be made based on the encoder count value θen. If it is determined that the motor 10 has not reached the target angle (S212: No), the current drive mode continues; if it is determined that the target angle has been reached (S212: Yes), it enters S213.

[0076] In S213, the control unit 50 switches the drive mode to failure (stop) mode and stops the motor 10 by energizing the two stationary phases. If the drive mode before entering failure (stop) mode was failure (two-phase drive) mode, the two stationary phases are energized normally. In failure (open circuit) mode, the processing of S212 and S213 is the same as that of S112 and S113. The processing of S214 and S215 is the same as that of S114 and S115.

[0077] based on Figure 9 The timing diagram illustrates the motor control processing when a non-conducting anomaly occurs in phase U. The processing from time x30 to time x32 is... Figure 7 The processing from time x20 to time x22 is the same. At time x32, if it is determined that the U phase is not conducting, the drive mode is switched to failure (two-phase drive) mode, and the motor 10 is driven by using the two-phase drive of the V phase and W phase.

[0078] At time x33, if the encoder count value θen reaches the target count value θcmd, the drive mode is switched to failure (stop) mode, and motor 10 is stopped by continuing to energize the fixed phases that energize phases V and W. The processing at time x34 is the same as... Figure 6 The processing of time x14 is the same.

[0079] In this embodiment, the drive control unit 53 switches to control the motor 10 by using a normal phase other than the determined faulty phase, thus continuing to drive the motor 10. Therefore, even if an abnormality occurs in the power supply system, the drive of the motor 10 can continue appropriately. Furthermore, in the wired shifting system 1, gear switching can be performed appropriately. In addition, the same effects as in the embodiment described above are achieved.

[0080] In the implementation, ECU40 corresponds to "motor control device", encoder 13 corresponds to "rotation angle sensor", and encoder count value θen corresponds to "motor rotation angle".

[0081] <Other Implementation Methods>

[0082] In the above embodiment, the switching element of the drive circuit is disposed between the winding of each phase and the ground wire. In other embodiments, the switching element can be disposed on the high-potential side of the winding of each phase, or on both the high-potential side and the ground side. In addition, the voltage determination threshold Vth, its magnitude, etc., can be appropriately changed according to the placement of the switching element.

[0083] In the above embodiment, an encoder is used as the rotation angle sensor. In other embodiments, the rotation angle sensor can be any device capable of detecting the rotational position of the rotor, such as a linear sensor like a resolver. In the above embodiment, a potentiometer is exemplified as the output shaft sensor. In other embodiments, sensors other than a potentiometer can be used as the output shaft sensor, or the output shaft sensor can be omitted.

[0084] In the above embodiment, the motor is a switched reluctance motor. In other embodiments, the motor may be a motor other than a switched reluctance motor, such as a DC brushless motor. In the above embodiment, four valleys are provided on the stop plate. In other embodiments, the number of valleys is not limited to four; any number is acceptable. For example, the stop plate may have two valleys to switch between P and non-P gears. Furthermore, the gear shifting mechanism, parking lock mechanism, etc., may differ from those in the above embodiment. Additionally, in the above embodiment, the motor control device is applied to the gear shifting system. In other embodiments, the motor control device may be applied to an on-board system other than the gear shifting system or a motor drive system other than an on-board system.

[0085] In the above embodiments, a speed reducer is provided between the motor shaft and the output shaft. Details of the speed reducer are not mentioned in the above embodiments, but it can have various structures, such as a speed reducer using cycloidal gears, planetary gears, spur gears that transmit torque from a reduction mechanism approximately coaxial with the motor shaft to the drive shaft, or a speed reducer using a combination of these. Furthermore, in other embodiments, the speed reducer between the motor shaft and the output shaft may be omitted, or a mechanism other than a speed reducer may be provided.

[0086] The control unit and methods described in this disclosure can also be implemented using a dedicated computer configured with a processor and memory programmed to perform one or more functions embodied in a computer program. Alternatively, the control unit and methods described in this disclosure can also be implemented using a dedicated computer configured with a processor using one or more dedicated hardware logic circuits. Alternatively, the control unit and methods described in this disclosure can also be implemented using one or more dedicated computers configured with a combination of a processor and memory programmed to perform one or more functions and a processor containing one or more hardware logic circuits. Furthermore, the computer program can also be stored as instructions to be executed by a computer on a computer-readable non-transitional tangible recording medium. As described above, this disclosure is not limited to the above embodiments and can be implemented in various ways without departing from its spirit.

[0087] This disclosure is described based on embodiments. However, this disclosure is not limited to these embodiments and structures. This disclosure also includes various modifications and equivalent variations. In addition, various combinations and methods, as well as other combinations and methods that include only one element, more elements, or fewer elements, also fall within the scope and spirit of this disclosure.

Claims

1. A motor control device for controlling the drive of a motor having motor windings, characterized in that, have: A drive circuit having switching elements; and The control unit includes an angle calculation unit, a drive control unit, and an anomaly diagnosis unit. The angle calculation unit obtains the detected value from the rotation angle sensor that detects the rotation angle of the motor, and calculates the motor rotation angle. The drive control unit controls the drive of the motor based on the motor rotation angle. When the abnormality diagnosis unit detects an abnormality in the motor rotation angle during the driving process of the motor, it performs abnormality diagnosis of the power supply system while maintaining the power supply state. The abnormality in the power supply system is a failure to conduct due to an open-circuit fault in the switching element. When the abnormality diagnosis unit detects an abnormality in the motor rotation angle during the driving process of the motor, before entering the control state where the motor rotation angle is not used, while maintaining the energized state when the abnormality was detected, it determines, based on the terminal voltage of the motor winding, whether the detected abnormality in the motor rotation angle is caused by an abnormality of the rotation angle sensor or by an open circuit fault of the switching element that causes a failure to conduct.

2. The motor control device according to claim 1, characterized in that, If the abnormality in the motor rotation angle is caused by a malfunction in the rotation angle sensor, the drive control unit switches to not using the motor rotation angle control and continues to drive the motor.

3. The motor control device according to claim 1 or 2, characterized in that, If the abnormality in the motor rotation angle is caused by a malfunction in the power supply system, the drive control unit cuts off the power supply to the motor.

4. The motor control device according to claim 1 or 2, characterized in that, When an abnormality in the motor rotation angle is detected, if the terminal voltage of the phase indicating power supply, i.e. the power supply indicator phase, is different from the normal value, the abnormality in the motor rotation angle is caused by an abnormality in the power supply system, and the abnormality diagnosis unit determines the power supply indicator phase as a faulty phase.

5. The motor control device according to claim 4, characterized in that, The drive control unit switches to using the normal phase (other than the faulty phase) to drive the motor instead of the faulty phase, and continues to drive the motor.

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