JP7415863B2 - motor control device - Google Patents

Description

The present disclosure relates to a motor control device.

As an example of a motor control device, there is a sliding door control device disclosed in Patent Document 1. The sliding door is driven to open and close 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 that drives a brushless motor. The door ECU includes a speed control section and a sensor failure detection section that detects a failure of the position sensor. The speed control section opens and closes the sliding door at high speed by driving the brushless motor at a first maximum speed during normal times when the position sensor is not out of order. Further, when a failure of the position sensor is detected, the speed control section opens and closes the sliding door at a low speed by driving the brushless motor at a second maximum speed that is smaller than the first maximum speed.

Japanese Patent Application Publication No. 2014-181544

However, if the Hall sensor fails, the sliding door control device may not be able to correctly recognize the rotor position and may erroneously energize the motor.

One object of the disclosure is to provide a motor drive device that can appropriately energize a three-phase motor even when one Hall sensor fails.

The motor control device disclosed herein is
A motor control device that receives sensor signals from three Hall sensors for detecting the position of a rotor in a three-phase motor, and controls the drive of the three-phase motor by switching an energization pattern to the three-phase motor,
a storage unit (11b) storing energization pattern information in which each combination of the three sensor signals and a plurality of energization patterns are associated with each rotor position;
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 section is
A failure determination unit (S10, S11) that determines failure of the Hall sensor;
a signal detection unit (S21a to S21c, S40a to S40c) that detects sensor signals;
When a failure of only one Hall sensor is detected, a failure drive unit (which controls the drive of the three-phase motor based on the sensor signals and energization pattern information of the two normal Hall sensors for which no failure has been detected) is activated. S13-S15) and
The processing unit includes a time prediction unit (S22, S28) that predicts the elapsed time between switching timings of the energization pattern,
At the time of failure, the drive unit is
In the energization pattern information, if the sensor signal of the normal sensor changes in response to a change in the rotor position, the energization pattern is switched at the timing when the sensor signal of the normal sensor detected by the signal detection section changes,
If the sensor signal of the normal sensor does not change with respect to a change in the position of the rotor in the energization pattern information, the energization pattern is switched at a timing when an elapsed time has elapsed since the previous energization pattern switching timing.

In this manner, the motor control device includes a failure drive unit that controls the drive of 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 multiple embodiments disclosed in this specification employ different technical means to achieve their respective objectives. The claims and the reference numerals in parentheses described in this section exemplarily indicate correspondence with parts of the embodiment described later, and are not intended to limit the technical scope. The objects, features, and advantages disclosed in this specification will become more apparent by reference to the subsequent detailed description and accompanying drawings.

FIG. 1 is a block diagram showing a schematic configuration of a motor control device in an embodiment. It is a flowchart which shows processing operation of a motor control device in an embodiment. It is a flowchart which shows the processing operation of a motor control device when a U-phase Hall sensor fails in an embodiment. It is a flowchart showing the processing operation of the motor control device when a compare match interrupt occurs in the embodiment. It is a drawing showing the commutation timing of the motor control device when a U-phase Hall sensor fails in the embodiment. It is a flowchart which shows the processing operation of a motor control device when a V-phase Hall sensor fails in an embodiment. It is a flowchart showing the processing operation of the motor control device when a compare match interrupt occurs in the embodiment. It is a drawing showing the commutation timing of the motor control device when a V-phase Hall sensor fails in the embodiment. It is a flowchart which shows the processing operation of the motor control device when the W-phase Hall sensor fails in the embodiment. It is a flowchart showing the processing operation of the motor control device when a compare match interrupt occurs in the embodiment. It is a drawing showing the commutation timing of the motor control device when a W-phase Hall sensor fails in the embodiment.

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

<Configuration>
The configuration of the ECU 10 will be explained using FIG. 1. The ECU 10 is electrically connected to a three-phase motor 30 (M) mounted on the vehicle. Then, the ECU 10 drives and controls the three-phase motor 30.

Three-phase motor 30 is a brushless motor. The three-phase motor 30 is drive-controlled by the ECU 10 and drives, 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, for example, three Y-connected coils: a U-phase coil, a V-phase coil, and a W-phase coil. For example, two-pole permanent magnets are attached to the rotor. Furthermore, the three-phase motor 30 includes three Hall sensors 21 to 23 as position detection means for detecting the rotational position (position, magnetic pole position) of the rotor.

Specifically, the three-phase motor 30 is provided with three Hall sensors 21 to 23 corresponding to each phase: U phase, V phase, and W phase. Reference numeral 21 indicates 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).

Each of the Hall sensors 21 to 23 can employ, for example, an integrated circuit (Hall IC) incorporating a Hall element. 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 a 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. Furthermore, the microcomputer 11 includes a compare match timer 11c (CMT).

The microcomputer 11 is electrically connected to each Hall sensor 21-23. Therefore, the microcomputer 11 receives 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 section. The CPU 11a performs various calculation processes by executing programs 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), and time measurement. Hereinafter, the Hall sensor level will also be referred to as a sensor level.

The CPU 11a detects a Hi sticking failure of each of the Hall sensors 21 to 23 as failure detection of each 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) to determine the sensor level. Note that 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 the W-phase level.

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

To measure time, the CPU 11a measures the time required for the electrical angle to advance by 60 degrees using, for example, a timer. In other words, the CPU 11a acquires the time measured by the timer. This time is set as a compare match value.

In this embodiment, as an example, commutation timing is controlled so that the rotor position sequentially moves through six sections. Each section has an electrical angle of 60 degrees. Note that the processing operation of the microcomputer 11 will be explained in detail later.

The memory device 11b corresponds to a storage section. The memory device 11b may be provided by a semiconductor memory, a magnetic disk, or the like as a storage medium. Furthermore, the memory device 11b includes volatile memory and nonvolatile memory. The memory device 11b stores energization pattern information.

In the energization pattern information, as shown in FIG. 5, each combination of three sensor signals and a plurality of energization patterns are associated with each rotor position. To be more specific, in the energization pattern information, each combination of the levels of the three sensor signals is associated with an energization pattern. Note that FIG. 5 shows an example in which the U-phase Hall sensor 21 is stuck in Hi state. Furthermore, the level (L) in parentheses in FIG. 5 is the 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. In the second period (2 sec), the sensor level combination HLH and the second energization pattern (2EP) are associated. In the third section (3 sec), the sensor level combination LLH and the third energization pattern (3EP) are associated. In the fourth section (4 sec), the sensor level combination LHH and the fourth energization pattern (4EP) are associated. In the fifth section (5 sec), the sensor level combination LHL and the fifth energization pattern (5EP) are associated. In the sixth section (6 sec), the sensor level combination HHL and the sixth energization pattern (6EP) are associated.

The compare match timer 11c measures time by counting a clock or the like. Then, the compare match timer 11c compares the measured time (count value) and a set value, and generates an interrupt if they match. Specifically, the compare match timer 11c starts measuring 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 explained in detail later.

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

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

The drive instruction is input from the operating device to the ECU 10 by, for example, a user operating the operating device. However, the drive instruction may be input to the ECU 10 from another ECU without depending on the user's operation.

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 section). The CPU 11a determines the failure of the three Hall sensors 21-23. For example, the CPU 11a determines that a failure has occurred when each sensor level does not change for a certain period of time. In other words, the CPU 11a determines that among the three Hall sensors 21 to 23, the Hall sensor whose sensor level does not change for a certain period of time is faulty.

If the CPU 11a determines that all three Hall sensors 21 to 23 are not faulty, it considers all phases to be normal and proceeds to step S12. When the CPU 11a determines that only the U-phase Hall sensor 21 is malfunctioning, the process proceeds to step S13. If the CPU 11a determines that only the V-phase Hall sensor 22 is in failure, the CPU 11a proceeds to step S14. When the CPU 11a determines that only the W-phase Hall sensor 23 is malfunctioning, the process proceeds to step S15. If the CPU 11a determines that the plurality of Hall sensors are out of order, the CPU 11a proceeds to step S16.

In step S12, commutation timing control is performed from three sensor levels (normal drive section). If no failure is detected in the three Hall sensors 21 to 23, the CPU 11a performs commutation timing control from the U-phase level, V-phase level, and 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.

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. Note that it can also 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 patterns 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 instructing the acquired energization pattern to the driver circuit 12. The driver circuit 12 switches energization to each phase of the three-phase motor 30 in response to a control signal from the CPU 11a. In this way, the CPU 11a performs commutation timing control. In other words, the microcomputer 11 performs drive control of the three-phase motor 30 by the CPU 11a performing commutation timing control.

For example, when the sensor level combination changes from HLL to HLH, the CPU 11a acquires the second energization pattern associated with the sensor level combination HLH. Then, the CPU 11a outputs a control signal instructing the acquired second energization pattern to the driver circuit 12. The driver circuit 12 switches the energization to each phase of the three-phase motor 30 in accordance with the control signal from the CPU 11a so as to adopt the second energization pattern. 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 combination of sensor levels 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 combination of sensor levels 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 fifth energization pattern at the timing when the combination of sensor levels changes from LHH to LHL. The CPU 11a switches to the sixth energization pattern at the timing when the combination of sensor levels changes from LHL to HHL. The CPU 11a switches to the first energization pattern at the timing when the combination of sensor levels changes from HHL to HLL.

In step S13, commutation timing control is performed from two sensor levels, the V-phase level and the W-phase level (fault drive section). 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 in 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 (failure drive unit). 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 (failure drive unit). In this case, the U-phase Hall sensor 21 and the V-phase Hall sensor 22 correspond to normal sensors.

In this way, when a failure of only one Hall sensor is detected, the CPU 11a performs commutation timing control 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, energization pattern information, and the like. Note that the commutation timing control in steps S13 to S15 will be explained in detail later.

In step S16, commutation timing control is not performed. If the plurality of Hall sensors 21 to 23 are out of order, the CPU 11a cannot accurately estimate the position of the rotor. Therefore, the CPU 11a does not perform commutation timing control. In other words, the CPU 11a stops controlling the drive of the three-phase motor 30. Note that at least two of the plurality of Hall sensors 21 to 23 are out of order.

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, an audio output device, etc. provided in the vehicle, and provides notification via these devices. In other words, the CPU 11a notifies the user that the plurality of Hall sensors 21 to 23 are out of order. Thereby, the ECU 10 can prompt the user to repair or replace the Hall sensors 21 to 23 and the three-phase motor 30.

Further, the CPU 11a may notify via the wireless communication device that the plurality of Hall sensors 21 to 23 are out of order. In other words, 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. Thereby, the ECU 10 can notify the center worker that the plurality of Hall sensors 21 to 23 and the three-phase motor 30 are out of order.

Note that the center device is a device installed at 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 the plurality of Hall sensors 21 to 23 are out of order.

Furthermore, the CPU 11a may store the failure information in the memory device 11b. In this case, the memory device 11b is such that the stored contents can be read from outside the ECU 10. Therefore, the failure information stored in the memory device 11b is read by a reading device at a factory, a dealer, or the like. Thereby, the ECU 10 can notify workers at factories, dealers, etc. 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, commutation timing control in step S13 will be explained using FIGS. 3, 4, and 5. When the ECU 10 determines that only the U-phase Hall sensor 21 is in failure, the ECU 10 starts the process shown in the flowchart of FIG. 3 .

In step S20, it is determined whether the three-phase motor is stopped. If the CPU 11a is outputting the control signal, the CPU 11a does not determine that the three-phase motor 30 is stopped and proceeds to step S21a. If no control signal is being output, 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 section). The CPU 11a determines whether the V phase level is an H level or an 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 process proceeds to step S22. When the CPU 11a determines that the V phase level is L level and the W phase level is H level, the process 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 process 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 process proceeds to step S30.

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

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

Further, as described above, the CPU 11a controls the commutation timing so that the rotor position sequentially moves through an electrical angle of 60 degrees. Therefore, it can be said that the CPU 11a predicts the elapsed time between switching timings of the energization pattern. Furthermore, it can be said that the CPU 11a performs interval measurement.

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

In step S23a, the first energization pattern is used (failure drive unit). The CPU 11a acquires (determines) the energization pattern from the sensor level of the normal sensor and the energization pattern information. In this case, the CPU 11a acquires the first energization pattern because the V phase level is the L level and the W phase level is the L level. 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 L level and the W phase level changes to L level. Thereby, the CPU 11a performs commutation timing control in the same manner as described above.

Note that the CPU 11a temporarily stores, for example, the current sensor level or a value correlated to the current sensor level in the memory device 11b. This is because the energization pattern is switched depending on the change in the sensor level. The CPU 11a may store the current energization pattern or 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 section measurement is in progress. In step S22, the CPU 11a determines whether section measurement is in progress. If the CPU 11a determines that the section is being measured, the process proceeds to step S25, and if the CPU 11a does not determine that the section is being measured, the process proceeds to step S27a.

In step S25, the electrical angle 60° time is obtained. The CPU 11a acquires the time of 60 degrees of electrical angle for which measurement is started in step S22.

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

In step S27a, the second energization pattern is used (failure drive unit). The CPU 11a acquires the 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 obtains 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 instructing 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. Thereby, the CPU 11a performs commutation timing control in the same manner as described above. In this way, when the sensor signal of the normal sensor changes in response to a 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 similar to step S22.

In step S29a, the fourth energization pattern is used (failure drive unit). Similarly to step S23a, the CPU 11a obtains the energization pattern from the sensor level of the normal sensor and the energization pattern information. In this case, the CPU 11a acquires the fourth energization pattern because the V phase level is the H level and the W phase level is the H level. The CPU 11a outputs a control signal instructing the fourth energization pattern to the driver circuit 12. Thereby, the CPU 11a performs commutation timing control in the same manner as described above.

Note that, before executing step S29a, the CPU 11a executes step S41a using a compare match interrupt, which will be described later. That is, the CPU 11a executes commutation timing control in the third energization pattern before executing 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 has changed 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 explained in detail later.

Steps S30 to S32 are similar to steps S24 to S26.

In step S33a, the fifth energization pattern is used (failure drive section). Similarly to step S27a, the CPU 11a obtains 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 obtains 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 instructing 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. Thereby, the CPU 11a performs commutation timing control in the same manner as described above. In this way, as in step S27a, the CPU 11a switches the energization pattern at the timing when the sensor signal of the normal sensor detected in step S21a changes.

In step S34, a three-phase motor starting sequence is performed (forced drive unit). The CPU 11a forcibly rotates the three-phase motor 30 in order to detect (determine) a failure of the Hall sensors 21 to 23. Thereby, the ECU 10 can drive the three-phase motor 30 and 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 explained using FIG. 4. The compare match timer 11c starts measuring 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 a compare match interrupt occurs when only the U-phase Hall sensor is determined to be faulty, the ECU 10 starts the process shown in the flowchart of FIG. 4.

By the way, as described above, the compare match value is the elapsed time from when the energization pattern is switched until the next energization pattern is switched. When the compare match value is set in step S26, the CPU 11a sets the energization pattern to 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 to 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 similar to step S21a.

In step S41a, the third energization pattern is used (failure drive unit). Similarly to step S23a, the CPU 11a obtains the 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 a compare match interrupt occurs and the V phase level is at L level and the W phase level is at 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 (failure drive unit). Similarly to step S23a, the CPU 11a obtains the 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 a compare match interrupt occurs, the V phase level is H level, and the W phase level is 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.

In this manner, if the sensor signal of the normal sensor does not change with respect to a change in the rotor position in the energization pattern information, the CPU 11a switches the energization pattern at the timing when the elapsed time has elapsed since the previous energization pattern switching timing. That is, if the sensor signal of the normal sensor does not change with respect to a 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 this embodiment, whether the Hall sensors 21 to 23 are normal or malfunctioning, common energization pattern information is used to obtain the energization pattern. However, the present disclosure is not limited thereto. In the present disclosure, the energization pattern may be acquired using normal pattern information and failure pattern information as the energization pattern information.

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

The failure pattern information is energization pattern information used when only one of the three Hall sensors 21 to 23 is out of order. In the failure pattern information, a combination of sensor signals of normal sensors and an energization pattern are associated. In other words, the failure pattern information is the normal pattern information minus the sensor signal of the failed Hall sensor. Therefore, the memory device 11b can be used in three failure situations: when the U-phase Hall sensor 21 is out of order, when the V-phase Hall sensor 22 is out of order, and when the W-phase Hall sensor 23 is out of order. Stores pattern information.

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

<When V-phase Hall sensor fails>
Next, commutation timing control in step S14 will be explained using FIGS. 6, 7, and 8. When the ECU 10 determines that only the V-phase Hall sensor is malfunctioning, it starts the process shown in the flowchart of FIG. 6 . Note that in the flowchart of FIG. 6, the same step numbers are assigned to the same processes as in the flowchart of FIG. Here, processing different from the flowchart in FIG. 3 will be explained.

FIG. 8 shows an example in which the V-phase Hall sensor 22 is stuck in Hi state. Furthermore, the level (L) in parentheses in FIG. 8 is the level that should 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 section). The CPU 11a determines whether the U phase level is an H level or an 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 H level and the W phase level is H level, the process proceeds to step S22. When the CPU 11a determines that the U phase level is L level and the W phase level is H level, the process proceeds to step S24. If the CPU 11a determines that the U phase level is the L level and the W phase level is the L level, the process proceeds to step S28. When the CPU 11a determines that the U phase level is H level and the W phase level is L level, the process 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 patterns to be acquired are different from those in the above embodiment.

In step S23b, the second energization pattern is used (failure drive unit). Since the U phase level is H level and the W phase level is H level, the CPU 11a acquires the second energization pattern. Moreover, before the CPU 11a controls commutation timing using the second energization pattern, the CPU 11a performs commutation timing using the first energization pattern. Therefore, since the W phase level has changed from the L level to the H 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 W-phase level changes from the L level to the H level.

In step S27b, the third energization pattern is used (failure drive unit). Since the U phase level has changed from the H level to the L level and the W phase level is the H level, the CPU 11a acquires the third energization pattern. The CPU 11a outputs a control signal instructing 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 (failure drive unit). 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, before executing step S29b, the CPU 11a executes step S41b using a compare match interrupt. That is, the CPU 11a executes commutation timing control in the fourth energization pattern before executing 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 is changing from the H level to the L level. Further, the CPU 11a outputs a control signal instructing 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 (failure drive section). Since the U phase level has changed from the L level to the H level and the W phase level is the L level, the CPU 11a acquires the sixth energization pattern. The CPU 11a outputs a control signal instructing 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 explained using FIG. 7. If a compare match interrupt occurs when 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, similarly to step S21b, the U-phase level and the W-phase level are determined (signal detection section). If the CPU 11a determines that the U phase level is the L level and the W phase level is the H level, the process proceeds to step S41b. When the CPU 11a determines that the U phase level is H level and the W phase level is L level, the process 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 the above embodiment.

In step S41b, the fourth energization pattern is used (failure drive unit). The CPU 11a acquires the fourth energization pattern because a compare match interrupt has occurred and the U phase level is at L level and the W phase level is at H level. 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 (failure drive unit). The CPU 11a acquires the first energization pattern because a compare match interrupt has occurred and the U phase level is H level and the W phase level is L level. 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 W-phase Hall sensor fails>
Next, commutation timing control in step S15 will be explained using FIGS. 9, 10, and 11. When the ECU 10 determines that only the W-phase Hall sensor is in failure, the ECU 10 starts the process shown in the flowchart of FIG. 9 . Note that in the flowchart of FIG. 9, the same step numbers are assigned to the same processes as in the flowchart of FIG. Here, processing different from the flowchart in FIG. 3 will be explained.

FIG. 11 shows an example in which the W-phase Hall sensor 23 is stuck in Hi state. Further, the level (L) in parentheses in FIG. 11 is the 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 section). The CPU 11a determines whether the U phase level is an H level or an L level. Further, the CPU 11a determines whether the V phase level is an H level or an 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. If the CPU 11a determines that the U-phase level is the L level and the V-phase level is the H level, the process proceeds to step S24. When the CPU 11a determines that the U phase level is H level and the V phase level is H level, the process proceeds to step S28. When the CPU 11a determines that the U phase level is H level and the V phase level is L level, the process 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 patterns to be acquired are different from those in the above embodiment.

In step S23c, the third energization pattern is used (failure drive unit). Since the U-phase level is L level and the V-phase level is L level, the CPU 11a acquires the third energization pattern. Furthermore, before the CPU 11a controls commutation timing using the third energization pattern, the CPU 11a performs commutation timing using the second energization pattern. Therefore, since the U-phase level has changed from the H level to the L level, the CPU 11a acquires the third energization pattern. The CPU 11a outputs a control signal instructing 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 (failure drive unit). Since the V-phase level has changed 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 instructing 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 (failure drive unit). Since the U phase level is H level and the V phase level is H level, the CPU 11a acquires the sixth energization pattern.

Note that, before executing step S29c, the CPU 11a executes step S41c using a compare match interrupt. That is, the CPU 11a executes commutation timing control in the fifth energization pattern before executing 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 has changed 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 instructing 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 (failure drive unit). Since the V phase level has changed 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 instructing 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 explained using FIG. 10. If a compare match interrupt occurs when only the W-phase Hall sensor is determined to be faulty, the ECU 10 starts the process shown in the flowchart of FIG. 10 .

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

Steps S41c and S42c are similar to steps S41a and S42a of the above embodiment. However, steps S41c and S42c differ in the energization pattern to be obtained from the above embodiment.

In step S41c, the fifth energization pattern is used (failure drive unit). The CPU 11a obtains the fifth energization pattern because a compare match interrupt has occurred and the U phase level is at the L level and the V phase level is at the H level. 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 (failure drive section). The CPU 11a obtains the second energization pattern because a compare match interrupt has occurred and the U phase level is H level and the V phase level is L level. 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>
In this way, when a failure of only one Hall sensor is detected, the ECU 10 controls the drive of 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 in response to a 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, if the sensor signal of the normal sensor does not change with respect to a change in the position of the rotor in the energization pattern information, the ECU 10 switches the energization pattern at a timing when an elapsed time has elapsed from the previous switching timing of the energization pattern. Therefore, the ECU 10 can appropriately energize the three-phase motor 30 even if only one Hall sensor fails.

Furthermore, some three-phase motors 30 are such that stopping the three-phase motor 30 is directly connected to stopping 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 embodiments, and various modifications can be made without departing from the spirit of the present disclosure.

Although the present disclosure has been described based on examples, it is understood that the present disclosure is not limited to the examples or structures. The present disclosure also includes various modifications and equivalent modifications. In addition, although various combinations and configurations are shown in this disclosure, other combinations and configurations including only one element, more, or fewer elements are also within the scope and spirit of this disclosure. It is something that can be entered.

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 that receives sensor signals from three Hall sensors for detecting the position of a rotor in a three-phase motor, and controls the drive of the three-phase motor by switching an energization pattern to the three-phase motor,
a storage unit (11b) storing energization pattern information in which each combination of the three sensor signals and the plurality of energization patterns are associated with each position of the rotor;
a processing unit (11a) that controls drive of the three-phase motor by switching the energization pattern to the three-phase motor based on the sensor signal and the energization pattern information;
The processing unit includes:
a failure determination unit (S10, S11) that determines failure of the Hall sensor;
a signal detection unit (S21a to S21c, S40a to S40c) that detects the sensor signal;
When a failure of only one Hall sensor is detected, drive control of the three-phase motor is performed based on the sensor signals of the two normal Hall sensors in which no failure has been detected and the energization pattern information. A failure drive unit (S13 to S15),
The processing unit includes a time prediction unit (S22, S28) that predicts the elapsed time between switching timings of the energization pattern,
The failure drive unit is
In the energization pattern information, when the sensor signal of the normal sensor changes with respect to a change in the position of the rotor, the energization pattern is changed at the timing when the sensor signal of the normal sensor detected by the signal detection section changes. switching,
If the sensor signal of the normal sensor does not change with respect to a change in the position of the rotor in the energization pattern information, the motor control switches the energization pattern at a 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 predicts the elapsed time by measuring the time between the switching timings multiple times and calculating an average value of the times measured multiple times. If a failure of the Hall sensors is not detected, the three-phase motor is activated 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 section (S12) that performs drive control. The storage unit stores, as the energization pattern information, normal pattern information when the three Hall sensors are normal, and failure pattern information when only one Hall sensor is malfunctioning;
The normal drive unit uses the normal pattern information as the energization pattern information,
5. The motor control device according to claim 4, wherein the failure drive unit uses the failure pattern information as the energization pattern information. A forced drive unit (S34) for forcibly controlling the drive of the three-phase motor in order for the failure determination unit to determine a failure of the Hall sensor when the three-phase motor is stopped. The motor control device according to any one of items 1 to 5.

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