JP2022051610A - Motor control device - Google Patents

Abstract

To provide a motor drive device capable of appropriately applying current to a three-phase motor even when one hall sensor fails.SOLUTION: CPU 11a drive-controls a three-phase motor 30 based on current-application pattern information and sensor signals of two normal sensors whose no failures are detected, when detecting failure of one hall sensor. The CPU 11a predicts a lapse time between switching timings of the current-application pattern. Then, the CPU 11a switches the current-application pattern at a timing when the sensor signals of the normal sensors change, in a case where the sensor signals of the normal sensors change with a change of a rotor according to the current-application pattern. Further, the CPU 11a switches the current-application pattern at a timing when the lapse time is elapsed from the switching timings of the current-application pattern, in a case where no sensor signals of the normal sensors change with the change at the rotor position according to the current-application pattern.SELECTED DRAWING: Figure 3

Description

The present disclosure relates to a motor control device.

As an example of the motor control device, there is a slide door control device disclosed in Patent Document 1. The sliding door is opened and closed by a brushless motor. The brushless motor is provided with three Hall sensors as rotor position sensors.

The sliding door control device includes a door ECU and a motor drive circuit for driving a brushless motor. The door ECU includes a speed control unit and a sensor failure detection unit that detects a failure of the position sensor. The speed control unit opens and closes the slide door at high speed by driving the brushless motor at the first maximum speed in the normal time when the position sensor is not out of order. Further, the speed control unit opens and closes the slide door at a low speed by driving the brushless motor at a second maximum speed smaller than the first maximum speed when the position sensor fails.

Japanese Unexamined Patent Publication No. 2014-181544

However, if the Hall sensor fails, the sliding door control device cannot correctly recognize the rotor position, and there is a possibility that the motor will be erroneously energized.

One object disclosed is to provide a motor drive that can adequately energize a three-phase motor even if one Hall sensor fails.

The motor control device disclosed here is
A motor control device that drives and controls a three-phase motor by inputting sensor signals from three Hall sensors for detecting the position of the rotor in the three-phase motor and switching the energization pattern to the three-phase motor.
A storage unit (11b) in which each combination of the three sensor signals and a plurality of energization patterns store energization pattern information associated with each rotor position, and
It has a processing unit (11a) that switches the energization pattern to the three-phase motor based on the sensor signal and the energization pattern information to drive and control the three-phase motor.
The processing unit
Failure determination units (S10, S11) that determine the failure of the Hall sensor, and
Signal detection units (S21a to S21c, S40a to S40c) that detect sensor signals, and
When a failure of only one Hall sensor is detected, a failure drive unit that drives and controls the three-phase motor based on the sensor signal of the normal sensor, which is two Hall sensors for which no failure is detected, and the energization pattern information ( S13 to S15) and
The processing unit includes a time prediction unit (S22, S28) that predicts the elapsed time between the switching timings of the energization pattern.
In the event of a failure, the drive unit
When the sensor signal of the normal sensor changes with respect to the change in the position of the rotor in the energization pattern information, the energization pattern is switched at the timing when the sensor signal of the normal sensor detected by the signal detection unit changes.
If the sensor signal of the normal sensor does not change in response to the change in the rotor position in the energization pattern information, the energization pattern is switched at the timing when the elapsed time has elapsed from the previous energization pattern switching timing.

As described above, the motor control device includes a failure drive unit that drives and controls the three-phase motor when a failure of only one Hall sensor is detected. Therefore, the motor control device can appropriately energize the three-phase motor even if one Hall sensor fails.

The plurality of aspects disclosed herein employ different technical means to achieve their respective objectives. The claims and the reference numerals in parentheses described in this section exemplify the correspondence with the parts of the embodiments described later, and are not intended to limit the technical scope. The objectives, features, and effects disclosed herein will be further clarified by reference to the subsequent detailed description and accompanying drawings.

It is a block diagram which shows the schematic structure of the motor control device in an embodiment. It is a flowchart which shows the processing operation of the motor control device in embodiment. It is a flowchart which shows the processing operation of the motor control device at the time of the U-phase Hall sensor failure in embodiment. It is a flowchart which shows the processing operation of the motor control device at the time of occurrence of a compare match interrupt in an embodiment. It is a figure which shows the commutation timing of a motor control device at the time of a U-phase Hall sensor failure in an embodiment. It is a flowchart which shows the processing operation of the motor control device at the time of V-phase Hall sensor failure in embodiment. It is a flowchart which shows the processing operation of the motor control device at the time of occurrence of a compare match interrupt in an embodiment. It is a figure which shows the commutation timing of a motor control device at the time of a V-phase Hall sensor failure in an embodiment. It is a flowchart which shows the processing operation of the motor control device at the time of the W phase Hall sensor failure in embodiment. It is a flowchart which shows the processing operation of the motor control device at the time of occurrence of a compare match interrupt in an embodiment. It is a figure which shows the commutation timing of the motor control device at the time of the W phase Hall sensor failure in embodiment.

Hereinafter, embodiments for carrying out the present disclosure will be described with reference to the drawings. In this embodiment, an example in which the motor control device is applied to the ECU 10 is adopted. The ECU 10 is configured to be mounted on a vehicle, for example. ECU is an abbreviation for Electronic Control Unit.

<Structure>
The configuration of the ECU 10 will be described with reference to FIG. The ECU 10 is electrically connected to the three-phase motor 30 (M) mounted on the vehicle. Then, the ECU 10 drives and controls the three-phase motor 30.

The three-phase motor 30 is a brushless motor. The three-phase motor 30 is driven and controlled by the ECU 10 to drive, for example, a sliding door, an electric fan for cooling, an electric pump, and the like. However, the driving target is not limited to this.

The three-phase motor 30 includes a stator and a rotor. The stator has three coils, for example, a Y-connected U-phase coil, a V-phase coil, and a W-phase coil. The rotor is equipped with, for example, a two-pole permanent magnet. Further, the three-phase motor 30 includes three Hall sensors 21 to 23 as position detecting means for detecting the rotation position (position, magnetic pole position) of the rotor.

More specifically, the three-phase motor 30 is provided with three Hall sensors 21 to 23 corresponding to each of the U-phase, V-phase, and W-phase. Reference numeral 21 is a U-phase Hall sensor (1HS) corresponding to the U-phase. Reference numeral 22 is a V-phase Hall sensor (2HS). Reference numeral 23 is a W-phase Hall sensor (3HS).

For each Hall sensor 21 to 23, for example, an integrated circuit (Hall IC) in which a Hall element is incorporated can be adopted. Each Hall sensor 21 to 23 is electrically connected to the ECU 10. Each Hall sensor 21 to 23 individually outputs a sensor signal (HSS). That is, the U-phase Hall sensor outputs the U-phase sensor signal. The V-phase Hall sensor outputs a V-phase sensor signal. The W-phase Hall sensor outputs a W-phase sensor signal.

The ECU 10 includes a microcomputer 11 (MC), a driver circuit 12 (DC), and the like. The microcomputer 11 includes at least one CPU 11a and at least one memory device 11b. Further, the microcomputer 11 includes a compare match timer 11c (CMT).

The microcomputer 11 is electrically connected to each of the hall sensors 21 to 23. Therefore, the microcomputer 11 is input with the three sensor signals output from each of the three Hall sensors 21 to 23. Further, the microcomputer 11 is electrically connected to the driver circuit 12.

The CPU 11a corresponds to a processing unit. The CPU 11a performs various arithmetic processes by executing a program stored in the memory device 11b. By performing arithmetic processing, the CPU 11a executes, for example, failure detection of each Hall sensor 21 to 23, determination of Hall sensor level (HSL), commutation timing control (CTC), time measurement, and the like. Hereinafter, the hall sensor level is also referred to as a sensor level.

The CPU 11a detects a Hi sticking failure of the Hall sensors 21 to 23 as a failure detection of the Hall sensors 21 to 23. However, the CPU 11a may detect a Lo sticking failure or the like.

The CPU 11a determines whether each sensor signal is H (high level) or L (low level) as a sensor level determination. The sensor level of the sensor signal of the U-phase Hall sensor 21 is referred to as a U-phase level. The sensor level of the sensor signal of the V-phase Hall sensor 22 is referred to as a V-phase level. The sensor level of the sensor signal of the W-phase Hall sensor 23 is referred to as a W-phase level.

The CPU 11a controls the switching of the energization pattern for the three-phase motor 30 and the switching timing as the commutation timing control. The CPU 11a outputs a control signal indicating an energization pattern to the driver circuit 12 at the timing when each sensor level changes. In this way, the CPU 11a controls the commutation timing. That is, the microcomputer 11 controls the drive of the three-phase motor 30 by controlling the commutation timing by the CPU 11a.

The CPU 11a measures the time required for the electric angle to advance by 60 ° by using, for example, a timer or the like. In other words, the CPU 11a acquires the time measured by the timer. This time is set as a compare match value.

In the present embodiment, as an example, an example of controlling the commutation timing so that the position of the rotor moves in six sections in order is adopted. Each section has an electrical angle of 60 °. The processing operation of the microcomputer 11 will be described in detail later.

The memory device 11b corresponds to a storage unit. The memory device 11b may be provided as a storage medium by a semiconductor memory, a magnetic disk, or the like. Further, the memory device 11b has a volatile memory and a non-volatile memory. The memory device 11b stores the energization pattern information.

As shown in FIG. 5, the energization pattern information is associated with each combination of the three sensor signals and a plurality of energization patterns for each rotor position. More specifically, the energization pattern information is associated with each combination of three sensor signal levels and the energization pattern. Note that FIG. 5 shows an example in which the U-phase Hall sensor 21 has a Hi sticking failure. The level (L) in parentheses in FIG. 5 is a level that should be recognized when the U-phase Hall sensor 21 is normal.

In the first section (1 sec), the sensor level combination HLL and the first energization pattern (1EP) are associated with each other. In the second section (2 sec), the sensor level combination HLH and the second energization pattern (2EP) are associated with each other. In the third section (3 sec), the sensor level combination LLH and the third energization pattern (3EP) are associated with each other. In the fourth section (4 sec), the sensor level combination LHH and the fourth energization pattern (4EP) are associated with each other. In the fifth section (5 sec), the sensor level combination LHL and the fifth energization pattern (5EP) are associated with each other. In the sixth section (6 sec), the sensor level combination HHL and the sixth energization pattern (6EP) are associated with each other.

The compare match timer 11c measures the time by counting the clock or the like. Then, the compare match timer 11c compares the measured time (count value) with the set value, and if they match, an interrupt is generated. Specifically, the compare match timer 11c starts measuring the time when the compare match value is set. Then, the compare match timer 11c generates an interrupt to the CPU 11a when the measured time and the compare match value match. The compare match value will be described in detail later.

The driver circuit 12 includes an inverter circuit having a switching element. The driver circuit 12 switches the energization of each phase of the three-phase motor 30 according to the control signal from the microcomputer 11 (CPU 11a). The driver circuit 12 outputs a drive signal DS for each phase coil of the three-phase motor 30.

<Processing operation>
The processing operation of the ECU 10 will be described with reference to FIGS. 2 to 11. When the drive instruction of the three-phase motor 30 is input, the ECU 10 starts the process shown in the flowchart of FIG. The process of the ECU 10 is mainly a process executed by the CPU 11a.

The drive instruction is input to the ECU 10 from the operating device, for example, by the user operating the operating device. However, the drive instruction may be input to the ECU 10 from another ECU regardless of the operation by the user.

In step S10, the failure state of each Hall sensor is acquired (failure determination unit). The CPU 11a acquires each sensor level as a failure state. That is, the CPU 11a acquires each sensor level as information for determining the failure state.

In step S11, a failure of each Hall sensor is determined (failure determination unit). The CPU 11a determines the failure of the three Hall sensors 21 to 23. The CPU 11a determines, for example, a failure when each sensor level does not change for a certain period of time. In other words, among the three hall sensors 21 to 23, the CPU 11a determines that the hall sensor whose sensor level does not change for a certain period of time is a failure.

If the CPU 11a determines that all of the three Hall sensors 21 to 23 are not faulty, the CPU 11a considers all phases to be normal and proceeds to step S12. If the CPU 11a determines that only the U-phase Hall sensor 21 has failed, the process proceeds to step S13. If the CPU 11a determines that only the V-phase Hall sensor 22 has failed, the process proceeds to step S14. If the CPU 11a determines that only the W-phase Hall sensor 23 has failed, the process proceeds to step S15. Then, when the CPU 11a determines that the plurality of Hall sensors have failed, the CPU 11a proceeds to step S16.

In step S12, commutation timing control is performed from three sensor levels (normal drive unit). When the failure of the three Hall sensors 21 to 23 is not detected, the CPU 11a controls the commutation timing from the U-phase level, the V-phase level, and the W-phase level. That is, the CPU 11a drives and controls the three-phase motor 30 based on the sensor signals of the three Hall sensors 21 to 23 and the energization pattern information at the timing when the sensor signals of the three Hall sensors 21 to 23 change.

More specifically, the CPU 11a determines three sensor levels. When the three sensor levels change, the CPU 11a refers to the energization pattern information stored in the memory device 11b. That is, the CPU 11a refers to the energization pattern information when at least one of the three sensor levels changes. It can be said that the CPU 11a estimates the position of the rotor in the three-phase motor 30 based on the three sensor levels.

The CPU 11a acquires the energization pattern associated with the three changed sensor levels. That is, the CPU 11a acquires information indicating the energization pattern. Then, the CPU 11a outputs a control signal indicating the acquired energization pattern to the driver circuit 12. The driver circuit 12 switches the energization of each phase of the three-phase motor 30 according to the control signal from the CPU 11a. In this way, the CPU 11a controls the commutation timing. In other words, the microcomputer 11 controls the drive of the three-phase motor 30 by controlling the commutation timing by the CPU 11a.

For example, when the sensor level combination changes from HLL to HLH, the CPU 11a acquires a second energization pattern associated with the sensor level combination HLH. Then, the CPU 11a outputs a control signal indicating the acquired second energization pattern to the driver circuit 12. The driver circuit 12 switches the energization of each phase of the three-phase motor 30 so as to have a second energization pattern according to the control signal from the CPU 11a. In this way, the CPU 11a switches the energization pattern to the three-phase motor 30 from the first energization pattern to the second energization pattern at the timing when the sensor level combination changes from HLL to HLH.

Similarly, the CPU 11a switches from the second energization pattern to the third energization pattern at the timing when the sensor level combination changes from HLH to LLH. The CPU 11a switches to the fourth energization pattern at the timing when the combination of sensor levels changes from LLH to LHH. The CPU 11a switches to the timing fifth energization pattern in which the combination of sensor levels changes from LHH to LHL. The CPU 11a switches to the timing sixth energization pattern in which the combination of sensor levels changes from LHL to HHL. The CPU 11a switches to the timing first energization pattern in which the combination of sensor levels changes from HHL to HLL.

In step S13, commutation timing control is performed from two sensor levels, V-phase level and W-phase level (drive unit at the time of failure). In this case, the V-phase Hall sensor 22 and the W-phase Hall sensor 23 correspond to normal sensors. A normal sensor is a hall sensor for which no failure has been detected.

In step S14, commutation timing control is performed from two sensor levels, the U phase level and the W phase level (drive unit at the time of failure). In this case, the U-phase hall sensor 21 and the W-phase hall sensor 23 correspond to normal sensors.

In step S15, commutation timing control is performed from two sensor levels, the U-phase level and the V-phase level (drive unit at the time of failure). In this case, the U-phase Hall sensor 21 and the V-phase Hall sensor 22 correspond to normal sensors.

As described above, when the failure of only one Hall sensor is detected, the CPU 11a controls the commutation timing by using the sensor signal (sensor level) of the normal sensor. That is, the CPU 11a drives and controls the three-phase motor 30 based on the sensor level of the normal sensor, the energization pattern information, and the like. The commutation timing control in steps S13 to S15 will be described in detail later.

In step S16, the commutation timing control is not performed. The CPU 11a cannot accurately estimate the position of the rotor when a plurality of Hall sensors 21 to 23 are out of order. Therefore, the CPU 11a does not control the commutation timing. That is, the CPU 11a stops the drive control of the three-phase motor 30. It should be noted that the plurality of Hall sensors 21 to 23 that are out of order are at least two in the plurality of Hall sensors 21 to 23.

The CPU 11a may notify that the plurality of Hall sensors 21 to 23 are out of order. In this case, the CPU 11a outputs an instruction signal to an indicator, a display device, a voice output device, or the like provided in the vehicle, and notifies the user via these devices. That is, the CPU 11a notifies the user that the plurality of Hall sensors 21 to 23 are out of order. As a result, the ECU 10 can urge the user to repair or replace the Hall sensors 21 to 23 and the three-phase motor 30.

Further, the CPU 11a may notify that the plurality of Hall sensors 21 to 23 are out of order via the wireless communication device. That is, the CPU 11a notifies a worker outside the vehicle that the plurality of Hall sensors 21 to 23 are out of order. In this case, the CPU 11a transmits the failure information to the center device via the wireless communication device. As a result, the ECU 10 can notify the operator of the center that the plurality of Hall sensors 21 to 23 and the three-phase motor 30 are out of order.

The center device is a device installed in a center provided outside the vehicle. The center device is a computer equipped with a CPU, a memory device, and the like. The failure information is information indicating that a plurality of Hall sensors 21 to 23 are out of order.

Further, the CPU 11a may store the failure information in the memory device 11b. In this case, the memory device 11b makes it possible to read the stored contents from the outside of the ECU 10. Therefore, the failure information stored in the memory device 11b is read by a reading device in a factory, a dealer, or the like. As a result, the ECU 10 can notify workers such as factories and dealers that the plurality of Hall sensors 21 to 23 and the three-phase motor 30 are out of order.

<When U-phase Hall sensor fails>
Here, the commutation timing control in step S13 will be described with reference to FIGS. 3, 4, and 5. When the ECU 10 determines that only the U-phase Hall sensor 21 has failed, the ECU 10 starts the process shown in the flowchart of FIG.

In step S20, it is determined whether or not the three-phase motor is stopped. When the CPU 11a outputs a control signal, the CPU 11a proceeds to step S21a without determining that the three-phase motor 30 is stopped. When the CPU 11a does not output the control signal, the CPU 11a determines that the three-phase motor 30 is stopped and proceeds to step S34.

In step S21a, the V-phase level and the W-phase level are determined (signal detection unit). The CPU 11a determines whether the V phase level is the H level or the L level. Further, the CPU 11a determines whether the W phase level is the H level or the L level. In other words, the CPU 11a detects the sensor signal.

When the CPU 11a determines that the V phase level is the L level and the W phase level is the L level, the CPU 11a proceeds to step S22. When the CPU 11a determines that the V phase level is the L level and the W phase level is the H level, the CPU 11a proceeds to step S24. When the CPU 11a determines that the V phase level is the H level and the W phase level is the H level, the CPU 11a proceeds to step S28. When the CPU 11a determines that the V phase level is the H level and the W phase level is the L level, the CPU 11a proceeds to step S30.

In step S22, the measurement of the electric angle of 60 ° is started (time prediction unit). The CPU 11a measures the time required for the electric angle to advance by 60 °. The CPU 11a measures the time in order to determine the switching timing of the section in which the sensor level of the normal sensor does not change with respect to the actual change in the rotor position.

The CPU 11a measures the time required for the electric angle to advance by 60 ° in order to predict the elapsed time between the switching timings of the energization pattern. That is, the CPU 11a measures the elapsed time until the energization pattern is actually switched and then the energization pattern is switched. The time required for the electric angle to advance by 60 ° is a value set as a compare match value.

Further, as described above, the CPU 11a controls the commutation timing so that the position of the rotor moves in order in the section where the electric angle is 60 °. Therefore, it can be said that the CPU 11a predicts the elapsed time between the switching timings of the energization pattern. Further, it can be said that the CPU 11a performs section measurement.

However, the present disclosure is not limited to this. The CPU 11a may predict the elapsed time by measuring the time between the switching timings a plurality of times and calculating the average value of the measured times. As a result, the CPU 11a can more accurately determine the switching timing of the section in which the sensor level of the normal sensor does not change.

In step S23a, the first energization pattern is used (drive unit at the time of failure). The CPU 11a acquires (determines) an energization pattern from the sensor level of the normal sensor and the energization pattern information. In this case, since the V phase level is the L level and the W phase level is the L level, the CPU 11a acquires the first energization pattern. The CPU 11a outputs a control signal instructing the first energization pattern to the driver circuit 12 at the timing when the V phase level changes to the L level and the W phase level changes to the L level. As a result, the CPU 11a controls the commutation timing in the same manner as described above.

The CPU 11a temporarily stores, for example, a current sensor level or a value that correlates with the current sensor level in the memory device 11b. This is because the energization pattern is switched according to the change in the sensor level. The CPU 11a may store the current energization pattern and the current section instead of the sensor level. In this case, the CPU 11a determines the current sensor level from the current energization pattern and the current section.

In step S24, it is determined whether or not the section is being measured. The CPU 11a determines in step S22 whether or not the section is being measured. If the CPU 11a determines that the section is being measured, the process proceeds to step S25, and if it is not determined that the section is being measured, the CPU 11a proceeds to step S27a.

In step S25, the electric angle of 60 ° time is acquired. The CPU 11a acquires the time of the electric angle of 60 ° at which the measurement is started in step S22.

In step S26, the compare match value is set. The CPU 11a sets the time of the electric angle of 60 ° acquired in step S25 as the compare match value. At this time, the compare match timer 11c starts measuring the time.

In step S27a, the second energization pattern is used (drive unit at the time of failure). The CPU 11a acquires an energization pattern from the sensor level of the normal sensor and the energization pattern information. That is, the CPU 11a acquires the energization pattern from the change in the sensor level of the normal sensor and the energization pattern information.

In this case, the CPU 11a acquires the second energization pattern because the V phase level is the L level and the W phase level is changing from the L level to the H level. The CPU 11a outputs a control signal indicating the second energization pattern to the driver circuit 12 at the timing when the W phase level changes from the L level to the H level. As a result, the CPU 11a controls the commutation timing in the same manner as described above. As described above, when the sensor signal of the normal sensor changes with respect to the change in the position of the rotor in the energization pattern information, the CPU 11a switches the energization pattern at the timing when the sensor signal of the normal sensor detected in step S21a changes.

Step S28 is the same as step S22.

In step S29a, the fourth energization pattern is used (drive unit at the time of failure). Similar to step S23a, the CPU 11a acquires an energization pattern from the sensor level of the normal sensor and the energization pattern information. In this case, since the V phase level is the H level and the W phase level is the H level, the CPU 11a acquires the fourth energization pattern. The CPU 11a outputs a control signal indicating the fourth energization pattern to the driver circuit 12. As a result, the CPU 11a controls the commutation timing in the same manner as described above.

Note that the CPU 11a executes step S41a with a compare match interrupt, which will be described later, before executing step S29a. That is, the CPU 11a executes the commutation timing control in the third energization pattern before executing the commutation timing control in the fourth energization pattern. Therefore, it can be said that the CPU 11a acquires the fourth energization pattern because the V phase level changes from the L level to the H level and the W phase level is the H level. Further, the CPU 11a outputs a control signal instructing the fourth energization pattern at the timing when the V phase level changes from the L level to the H level. The compare match interrupt will be described in detail later.

Steps S30 to S32 are the same as steps S24 to S26.

In step S33a, the fifth energization pattern is used (drive unit at the time of failure). Similar to step S27a, the CPU 11a acquires an energization pattern from the change in the sensor level of the normal sensor and the energization pattern information.

In this case, the CPU 11a acquires the fifth energization pattern because the V phase level is the H level and the W phase level is changing from the H level to the L level. The CPU 11a outputs a control signal indicating the fifth energization pattern to the driver circuit 12 at the timing when the W phase level changes from the H level to the L level. As a result, the CPU 11a controls the commutation timing in the same manner as described above. In this way, the CPU 11a switches the energization pattern at the timing when the sensor signal of the normal sensor detected in step S21a changes, as in step S27a.

In step S34, the start sequence of the three-phase motor is executed (forced drive unit). The CPU 11a forcibly rotates the three-phase motor 30 in order to detect (determine) the failure of the hall sensors 21 to 23. As a result, the ECU 10 can drive the three-phase motor 30 to determine the failure of the hall sensors 21 to 23 even when the three-phase motor 30 is stopped.

The compare match interrupt processing will be described with reference to FIG. The compare match timer 11c starts measuring the time when the compare match value is set in steps S26 and S32. Then, the compare match timer 11c generates an interrupt to the CPU 11a when the measured time and the compare match value match. Therefore, when the compare match interrupt occurs while only the U-phase Hall sensor is determined to be faulty, the ECU 10 starts the process shown in the flowchart of FIG.

By the way, the compare match value is the elapsed time from the switching of the energization pattern to the next switching of the energization pattern as described above. When the compare match value is set in step S26, the CPU 11a sets the energization pattern as the second energization pattern. In this case, a compare match interrupt will occur at the timing of switching to the third energization pattern. Further, when the compare match value is set in step S32, the CPU 11a sets the energization pattern as the fifth energization pattern. In this case, a compare match interrupt will occur at the timing of switching to the sixth energization pattern.

Step S40a is the same as step S21a.

In step S41a, the third energization pattern is used (drive unit at the time of failure). Similar to step S23a, the CPU 11a acquires an energization pattern from the sensor level of the normal sensor and the energization pattern information. In this case, the CPU 11a acquires the third energization pattern because the compare match interrupt occurs, the V phase level is the L level, and the W phase level is the H level. The CPU 11a outputs a control signal instructing the third energization pattern to the driver circuit 12 at the timing when the compare match interrupt occurs.

In step S42a, the sixth energization pattern is used (drive unit at the time of failure). Similar to step S23a, the CPU 11a acquires an energization pattern from the sensor level of the normal sensor and the energization pattern information. In this case, the CPU 11a acquires the sixth energization pattern because the compare match interrupt occurs, the V phase level is the H level, and the W phase level is the L level. The CPU 11a outputs a control signal instructing the sixth energization pattern to the driver circuit 12 at the timing when the compare match interrupt occurs.

As described above, when the sensor signal of the normal sensor does not change with respect to the change in the position of the rotor in the energization pattern information, the CPU 11a switches the energization pattern at the timing when the elapsed time has elapsed from the switching timing of the previous energization pattern. That is, when the sensor signal of the normal sensor does not change with respect to the change in the position of the rotor in the energization pattern information, the CPU 11a forcibly switches the energization pattern based on the elapsed time.

In the present embodiment, the energization pattern is acquired by using the common energization pattern information regardless of whether the Hall sensors 21 to 23 are normal or have a failure. However, the present disclosure is not limited to this. In the present disclosure, the energization pattern may be acquired by using the normal pattern information and the failure pattern information as the energization pattern information.

The memory device 11b stores the normal pattern information and the failure pattern information. The normal pattern information is the energization pattern information used when the three Hall sensors 21 to 23 are normal. The normal pattern information is the same as the above-mentioned energization pattern information.

The failure pattern information is energization pattern information used when only one of the three Hall sensors 21 to 23 fails. The failure pattern information is associated with the combination of sensor signals of the normal sensor and the energization pattern. That is, the failure pattern information is obtained by removing the sensor signal of the failing Hall sensor from the normal pattern information. Therefore, the memory device 11b has three failures, one for when the U-phase hall sensor 21 is broken, one for when the V-phase hall sensor 22 is broken, and one for when the W-phase hall sensor 23 is broken. Stores pattern information.

In this case, when the three Hall sensors 21 to 23 are normal, the CPU 11a acquires an energization pattern using the normal pattern information. When the U-phase Hall sensor 21 is out of order, the CPU 11a acquires an energization pattern by using the failure time pattern information for when the U-phase Hall sensor 21 is out of order. When the V-phase Hall sensor 22 is out of order, the CPU 11a acquires an energization pattern by using the failure time pattern information for when the V-phase Hall sensor 22 is out of order. When the W-phase Hall sensor 23 is out of order, the CPU 11a acquires an energization pattern by using the failure-time pattern information for when the W-phase Hall sensor 23 is out of order. As a result, the ECU 10 can determine the energization pattern more easily than using the common energization pattern information when only one Hall sensor fails.

<When V-phase Hall sensor fails>
Next, the commutation timing control in step S14 will be described with reference to FIGS. 6, 7, and 8. When the ECU 10 determines that only the V-phase Hall sensor has failed, the ECU 10 starts the process shown in the flowchart of FIG. In the flowchart of FIG. 6, the same step number is assigned to the same process as that of the flowchart of FIG. Here, processing different from the flowchart of FIG. 3 will be described.

FIG. 8 shows an example in which the V-phase Hall sensor 22 has a Hi sticking failure. Further, the level (L) in parentheses in FIG. 8 is a level to be recognized when the V-phase Hall sensor 22 is normal.

In step S21b, the U-phase level and the W-phase level are determined (signal detection unit). The CPU 11a determines whether the U phase level is the H level or the L level. Further, the CPU 11a determines whether the W phase level is the H level or the L level. In other words, the CPU 11a detects the sensor signal.

When the CPU 11a determines that the U phase level is the H level and the W phase level is the H level, the CPU 11a proceeds to step S22. When the CPU 11a determines that the U phase level is the L level and the W phase level is the H level, the CPU 11a proceeds to step S24. When the CPU 11a determines that the U phase level is the L level and the W phase level is the L level, the CPU 11a proceeds to step S28. When the CPU 11a determines that the U phase level is the H level and the W phase level is the L level, the CPU 11a proceeds to step S30.

Steps S23b, S27b, S29b, and S33b are similar to steps S23a, S27a, S29a, and S33a of the above embodiment. However, in steps S23b, S27b, S29b, and S33b, the energization pattern to be acquired is different from that of the above embodiment.

In step S23b, the second energization pattern is used (drive unit at the time of failure). Since the U-phase level is the H level and the W-phase level is the H level, the CPU 11a acquires the second energization pattern. Further, the CPU 11a performs the commutation timing in the first energization pattern before controlling the commutation timing in the second energization pattern. Therefore, since the W phase level changes from the L level to the H level, the CPU 11a acquires the second energization pattern. The CPU 11a outputs a control signal indicating the second energization pattern to the driver circuit 12 at the timing when the W phase level changes from the L level to the H level.

In step S27b, the third energization pattern is used (drive unit at the time of failure). The CPU 11a acquires the third energization pattern because the U phase level changes from the H level to the L level and the W phase level is the H level. The CPU 11a outputs a control signal indicating the third energization pattern to the driver circuit 12 at the timing when the U phase level changes from the H level to the L level.

In step S29b, the fifth energization pattern is used (drive unit at the time of failure). Since the U-phase level is the L level and the W-phase level is the L level, the CPU 11a acquires the fifth energization pattern.

Note that the CPU 11a executes step S41b with a compare match interrupt before executing step S29b. That is, the CPU 11a executes the commutation timing control in the fourth energization pattern before executing the commutation timing control in the fifth energization pattern.

Therefore, it can be said that the CPU 11a acquires the fifth energization pattern because the U phase level is the L level and the W phase level changes from the H level to the L level. Further, the CPU 11a outputs a control signal indicating the fifth energization pattern to the driver circuit 12 at the timing when the W phase level changes from the H level to the L level.

In step S33b, the sixth energization pattern is used (drive unit at the time of failure). The CPU 11a acquires the sixth energization pattern because the U phase level changes from the L level to the H level and the W phase level is the L level. The CPU 11a outputs a control signal indicating the sixth energization pattern to the driver circuit 12 at the timing when the U phase level changes from the L level to the H level.

Next, the compare match interrupt processing will be described with reference to FIG. 7. When the compare match interrupt occurs while only the V-phase Hall sensor is determined to be faulty, the ECU 10 starts the process shown in the flowchart of FIG. 7.

In step S40b, as in step S21b, the U-phase level and the W-phase level are determined (signal detection unit). When the CPU 11a determines that the U phase level is the L level and the W phase level is the H level, the CPU 11a proceeds to step S41b. When the CPU 11a determines that the U phase level is the H level and the W phase level is the L level, the CPU 11a proceeds to step S42b.

Steps S41b and S42b are similar to steps S41a and S42a of the above embodiment. However, in steps S41b and S42b, the energization pattern to be acquired is different from that of the above embodiment.

In step S41b, the fourth energization pattern is used (drive unit at the time of failure). Since the compare match interrupt occurs and the U phase level is the L level and the W phase level is the H level, the CPU 11a acquires the fourth energization pattern. The CPU 11a outputs a control signal instructing the fourth energization pattern to the driver circuit 12 at the timing when the compare match interrupt occurs.

In step S42b, the first energization pattern is used (drive unit at the time of failure). Since the compare match interrupt occurs and the U phase level is the H level and the W phase level is the L level, the CPU 11a acquires the first energization pattern. The CPU 11a outputs a control signal instructing the first energization pattern to the driver circuit 12 at the timing when the compare match interrupt occurs.

<When the W-phase Hall sensor fails>
Next, the commutation timing control in step S15 will be described with reference to FIGS. 9, 10 and 11. When the ECU 10 determines that only the W-phase Hall sensor has failed, the ECU 10 starts the process shown in the flowchart of FIG. In the flowchart of FIG. 9, the same step number is assigned to the same process as that of the flowchart of FIG. Here, processing different from the flowchart of FIG. 3 will be described.

FIG. 11 shows an example in which the W-phase Hall sensor 23 has a Hi sticking failure. The level (L) in parentheses in FIG. 11 is a level that should be recognized when the W-phase Hall sensor 23 is normal.

In step S21c, the U-phase level and the V-phase level are determined (signal detection unit). The CPU 11a determines whether the U phase level is the H level or the L level. Further, the CPU 11a determines whether the V phase level is the H level or the L level. In other words, the CPU 11a detects the sensor signal.

When the CPU 11a determines that the U-phase level is the L level and the V-phase level is the L level, the CPU 11a proceeds to step S22. When the CPU 11a determines that the U phase level is the L level and the V phase level is the H level, the CPU 11a proceeds to step S24. When the CPU 11a determines that the U-phase level is the H level and the V-phase level is the H level, the CPU 11a proceeds to step S28. When the CPU 11a determines that the U phase level is the H level and the V phase level is the L level, the CPU 11a proceeds to step S30.

Steps S23c, S27c, S29c, and S33c are similar to steps S23a, S27a, S29a, and S33a of the above embodiment. However, in steps S23c, S27c, S29c, and S33c, the energization pattern to be acquired is different from that of the above embodiment.

In step S23c, the third energization pattern is used (drive unit at the time of failure). Since the U-phase level is the L level and the V-phase level is the L level, the CPU 11a acquires the third energization pattern. Further, the CPU 11a performs the commutation timing in the second energization pattern before controlling the commutation timing in the third energization pattern. Therefore, since the U phase level changes from the H level to the L level, the CPU 11a acquires the third energization pattern. The CPU 11a outputs a control signal indicating the third energization pattern to the driver circuit 12 at the timing when the U phase level changes from the H level to the L level.

In step S27c, the fourth energization pattern is used (drive unit at the time of failure). Since the V-phase level changes from the L level to the H level and the U-phase level is the L level, the CPU 11a acquires the fourth energization pattern. The CPU 11a outputs a control signal indicating the fourth energization pattern to the driver circuit 12 at the timing when the V phase level changes from the L level to the H level.

In step S29c, the sixth energization pattern is used (drive unit at the time of failure). Since the U-phase level is the H level and the V-phase level is the H level, the CPU 11a acquires the sixth energization pattern.

Note that the CPU 11a executes step S41c with a compare match interrupt before executing step S29c. That is, the CPU 11a executes the commutation timing control in the fifth energization pattern before executing the commutation timing control in the sixth energization pattern.

Therefore, it can be said that the CPU 11a acquires the sixth energization pattern because the U phase level changes from the L level to the H level and the V phase level is the H level. Further, the CPU 11a outputs a control signal indicating the sixth energization pattern to the driver circuit 12 at the timing when the V phase level changes from the L level to the H level.

In step S33c, the first energization pattern is used (drive unit at the time of failure). Since the V-phase level changes from the H level to the L level and the U-phase level is the H level, the CPU 11a acquires the first energization pattern. The CPU 11a outputs a control signal indicating the first energization pattern to the driver circuit 12 at the timing when the V phase level changes from the H level to the L level.

Next, the compare match interrupt processing will be described with reference to FIG. When the compare match interrupt occurs while only the W phase Hall sensor is determined to be faulty, the ECU 10 starts the process shown in the flowchart of FIG.

In step S40c, as in step S21c, the U-phase level and the V-phase level are determined (signal detection unit). When the CPU 11a determines that the U phase level is the L level and the V phase level is the H level, the CPU 11a proceeds to step S41c. When the CPU 11a determines that the U phase level is the H level and the V phase level is the L level, the CPU 11a proceeds to step S42c.

Steps S41c and S42c are similar to steps S41a and S42a of the above embodiment. However, in steps S41c and S42c, the energization pattern to be acquired is different from that of the above embodiment.

In step S41c, the fifth energization pattern is used (drive unit at the time of failure). Since the compare match interrupt occurs and the U phase level is the L level and the V phase level is the H level, the CPU 11a acquires the fifth energization pattern. The CPU 11a outputs a control signal instructing the fifth energization pattern to the driver circuit 12 at the timing when the compare match interrupt occurs.

In step S42c, the second energization pattern is used (drive unit at the time of failure). Since the compare match interrupt occurs and the U phase level is the H level and the V phase level is the L level, the CPU 11a acquires the second energization pattern. The CPU 11a outputs a control signal instructing the second energization pattern to the driver circuit 12 at the timing when the compare match interrupt occurs.

<Effect>
As described above, when the failure of only one Hall sensor is detected, the ECU 10 drives and controls the three-phase motor 30 based on the sensor signal of the normal sensor and the energization pattern information. That is, when the sensor signal of the normal sensor changes with respect to the change in the position of the rotor in the energization pattern information, the ECU 10 switches the energization pattern at the timing when the sensor signal of the normal sensor changes. Further, when the sensor signal of the normal sensor does not change with respect to the change in the position of the rotor in the energization pattern information, the ECU 10 switches the energization pattern at the timing when the elapsed time has elapsed from the switching timing of the previous energization pattern. Therefore, the ECU 10 can appropriately energize the three-phase motor 30 even if only one Hall sensor fails.

Further, in some three-phase motors 30, the stoppage of the three-phase motor 30 is directly linked to the stoppage of the vehicle. However, the ECU 10 can drive and control the three-phase motor 30 even if only one of the hall sensors fails. Therefore, the ECU 10 can prevent the vehicle from stopping even if only one of the hall sensors fails.

The preferred embodiments of the present disclosure have been described above. However, the present disclosure is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present disclosure.

The present disclosure has been described in accordance with the examples, but it is understood that the present disclosure is not limited to the examples and structures. The present disclosure also includes various variations and variations within a uniform range. In addition, although various combinations and forms are shown in this disclosure, other combinations and forms, including only one element, more, or less, are also within the scope and scope of this disclosure. It is something to enter.

10 ... ECU, 11 ... microcomputer, 11a ... CPU, 11b ... memory device, 11c ... compare match timer, 12 ... driver circuit, 21 ... U-phase hall sensor, 22 ... V-phase hall sensor, 23 ... W-phase hall sensor, 30 … Three-phase motor

Claims (6)

A motor control device in which sensor signals are input from three Hall sensors for detecting the position of a rotor in a three-phase motor, and the energization pattern for the three-phase motor is switched to drive and control the three-phase motor.
A storage unit (11b) in which each combination of the three sensor signals and the plurality of energization patterns store energization pattern information associated with each position of the rotor, and
It has a processing unit (11a) that switches the energization pattern to the three-phase motor based on the sensor signal and the energization pattern information to drive and control the three-phase motor.
The processing unit
A failure determination unit (S10, S11) for determining a failure of the Hall sensor, and
A signal detection unit (S21a to S21c, S40a to S40c) for detecting the sensor signal, and
When a failure of only one Hall sensor is detected, the three-phase motor is driven and controlled based on the sensor signal of the normal sensor which is the two Hall sensors for which the failure is not detected and the energization pattern information. When a failure occurs, the drive unit (S13 to S15) and
The processing unit includes a time prediction unit (S22, S28) that predicts the elapsed time between the switching timings of the energization pattern.
The drive unit at the time of failure
When the sensor signal of the normal sensor changes with respect to a change in the position of the rotor in the energization pattern information, the energization pattern is applied at the timing when the sensor signal of the normal sensor detected by the signal detection unit changes. switching,
When the sensor signal of the normal sensor does not change with respect to the change in the position of the rotor in the energization pattern information, the motor control for switching the energization pattern at the timing when the elapsed time has elapsed from the previous switching timing of the energization pattern. Device. The motor control device according to claim 1, wherein the time prediction unit predicts the elapsed time by measuring the time between the switching timings. The motor control device according to claim 1, wherein the time prediction unit measures the time between the switching timings a plurality of times and calculates an average value of the times measured a plurality of times to predict the elapsed time. When the failure of the Hall sensor is not detected, the three-phase motor is driven based on the sensor signals of the three Hall sensors and the energization pattern information at the timing when the sensor signals of the three Hall sensors change. The motor control device according to any one of claims 1 to 3, further comprising a normal drive unit (S12) for drive control. The storage unit stores, as the energization pattern information, normal pattern information when three Hall sensors are normal and failure pattern information when only one Hall sensor fails.
The normal drive unit uses the normal pattern information as the energization pattern information.
The motor control device according to claim 4, wherein the failure drive unit uses the failure pattern information as the energization pattern information. A claim that the failure determination unit includes a forced drive unit (S34) for forcibly driving and controlling the three-phase motor in order to determine the failure of the Hall sensor when the three-phase motor is stopped. The motor control device according to any one of 1 to 5.

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