Motor control device and motor control method

Abstract

A motor control apparatus includes a first storage unit that stores characteristic data related to drive control of a vehicle motor, a second storage unit that stores a vehicle type parameter related to a predetermined vehicle type, a processor that performs an arithmetic process related to drive control corresponding to the predetermined vehicle type based on the vehicle type parameter and the characteristic data, and a drive circuit that performs a drive process of the vehicle motor of the predetermined vehicle type based on a result of the arithmetic process, wherein when an abnormality has occurred in the processor, the drive circuit reads out the characteristic data from the first storage unit and reads out the vehicle type parameter from the second storage unit, and performs the arithmetic process related to the drive control corresponding to the predetermined vehicle type based on the vehicle type parameter and the characteristic data.

Description

Technical Field

[0001] This invention relates to motor control equipment and motor control methods. Background Technology

[0002] For example, electrified vehicles such as hybrid vehicles and electric vehicles are equipped with multiple motors, such as motors for driving the front or rear wheels and motors for generating electricity. The control device for each motor performs control processing by assigning a load to each motor by multiple microcontrollers, for example, having a built-in processor such as a central processing unit (CPU) (e.g., Japanese Unexamined Patent Application Publication No. 2018-109551 (JP 2018-109551 A)).

[0003] When an anomaly occurs in another microcontroller, one microcontroller performs control processing on behalf of the other to operate the motor normally. This achieves a fail-safe function.

[0004] Document JP 6777623 B2 discloses a device for correcting the operating commands of a work vehicle.

[0005] US2016 / 0373051 A1 discloses a motor bridge driver integrated circuit.

[0006] US2013 / 0116876 A1 discloses an electric vehicle and a method for controlling the electric vehicle in an emergency. Summary of the Invention

[0007] When the control processing of multiple motors is integrated into a single microcontroller, the load on the processor built into that microcontroller increases. Therefore, it is conceivable that a portion of the control processing is shared with, for example, an application-specific integrated circuit (ASIC). In this case, if an anomaly occurs in the microcontroller, the ASIC performs fail-safe functions by executing the microcontroller's control processing.

[0008] Furthermore, in order to enable the microcontroller to be installed on vehicles of various types, the microcontroller performs control processing by switching characteristic data related to motor drive control via software, in response to the vehicle type of the target vehicle. However, to reduce device costs, the ASIC does not have built-in memory that pre-stores characteristic data corresponding to the various vehicle types, thus the ASIC can only perform control processing based on the characteristics of a specific vehicle type.

[0009] Therefore, when an ASIC is used for a vehicle type that the ASIC does not support, the control device cannot properly drive and control the motor according to the characteristics of the vehicle type on which the control device is installed when an anomaly occurs in the microcontroller, so that the fail-safe function cannot be properly implemented.

[0010] In this regard, the present invention provides a motor control device that can suppress the increase in equipment cost and appropriately implement fail-safe functions in response to vehicle type.

[0011] A first aspect of the present invention relates to a motor control device, comprising a first storage unit, a second storage unit, a processor, and a drive circuit. The first storage unit is configured to store feature data related to drive control of a vehicle's motor. The second storage unit is configured to store vehicle type parameters related to a predetermined vehicle type. The processor is configured to perform arithmetic processing related to drive control corresponding to the predetermined vehicle type based on the vehicle type parameters and the feature data. The drive circuit is configured to perform drive processing of the vehicle's motor for the predetermined vehicle type based on the result of the arithmetic processing. The drive circuit is configured to: when an exception occurs in the processor, read the feature data from the first storage unit and the vehicle type parameters from the second storage unit, and perform arithmetic processing related to drive control corresponding to the predetermined vehicle type based on the vehicle type parameters and the feature data.

[0012] In the motor control device according to the first aspect, the first storage unit can be configured to store feature data corresponding to a vehicle type other than a predetermined vehicle type. The drive circuit can be configured to: when an exception occurs in the processor, correct the feature data based on the vehicle type parameter so that the feature data corresponds to the predetermined vehicle type, and use the corrected feature data for computational processing.

[0013] In the motor control device according to the first aspect, the first storage unit can be configured to store feature data corresponding to multiple vehicle types. The drive circuit can be configured to read feature data corresponding to a predetermined vehicle type among the multiple vehicle types from the first storage unit based on vehicle type parameters and use the feature data for computational processing.

[0014] In the motor control device according to the first aspect, the feature data may include the correlation between the motor's rotational speed and torque.

[0015] In the motor control device according to the first aspect, the feature data may include the correlation between the motor's torque and current values.

[0016] In the motor control device according to the first aspect, the vehicle type parameter may be the reduction ratio of the differential gear connected to the motor.

[0017] In the motor control device according to the first aspect, the drive circuit can be configured to receive a notification regarding the normality of the processor. The drive circuit can be configured to determine, based on the notification, whether an abnormality has occurred in the processor.

[0018] A second aspect of the present invention relates to a motor control method. The motor control method includes: a drive circuit determining, based on vehicle type parameters related to the drive control of a vehicle's motor and feature data related to a predetermined vehicle type, whether an anomaly has occurred in a processor, wherein the processor is configured to perform arithmetic processing related to the drive control corresponding to the predetermined vehicle type; when the drive circuit determines that an anomaly has occurred in the processor, the drive circuit reads feature data from a first storage unit and reads vehicle type parameters from a second storage unit, wherein the first storage unit is configured to store the feature data and the second storage unit is configured to store the vehicle type parameters; and the drive circuit performing arithmetic processing related to the drive control corresponding to the predetermined vehicle type based on the vehicle type parameters and the feature data.

[0019] According to the above aspects of the present invention, it is possible to suppress the increase in equipment costs and to appropriately implement fail-safe functions in response to vehicle type. Attached Figure Description

[0020] The features, advantages, and technical and industrial significance of exemplary embodiments of the present invention will now be described with reference to the accompanying drawings, wherein like reference numerals denote like elements, and wherein:

[0021] Figure 1 This is a configuration diagram showing an example of a motor control device;

[0022] Figure 2 This is a diagram illustrating an example of rotational speed-torque mapping data corresponding to multiple reduction ratios of the differential gear, which differ from one another for each vehicle type;

[0023] Figure 3 This is a graph showing an example of torque-current mapping data corresponding to the reduction ratios of the differential gears, which are different for each vehicle type;

[0024] Figure 4 This is a diagram illustrating an example of a method for obtaining rotational speed-torque mapping data and torque-current mapping data corresponding to the vehicle type on which the motor control device is installed.

[0025] Figure 5 This is a diagram illustrating another example of a method for obtaining rotational speed-torque mapping data and torque-current mapping data;

[0026] Figure 6This is a flowchart illustrating an example of CPU operation; and

[0027] Figure 7 This is a flowchart illustrating an example of ASIC operation. Detailed Implementation

[0028] Configuration example of motor control device

[0029] Figure 1 This is a configuration diagram illustrating an example of a motor control device 90. The motor control device 90 includes a microcontroller 1, an ASIC 2, an electronic control unit (ECU) 3, an accelerometer sensor 30, and a brake sensor 31, and is installed on an electrified vehicle (hereinafter referred to as "vehicle") such as a hybrid vehicle or an electric vehicle.

[0030] Motor control device 90 controls inverter circuits 40 and 41 connected to motors 50 and 51, respectively. Each of the inverter circuits 40 and 41 has, for example, multiple insulated-gate bipolar transistors (IGBTs) corresponding to the upper and lower arms of a three-phase circuit. On / off control is performed on each IGBT by pulse width modulation (PWM) signals received as input from ASIC 2.

[0031] Inverter circuits 40 and 41 generate three-phase AC current based on the PWM signal and output the three-phase AC current to motors 50 and 51 respectively. Inverter circuits 40 and 41 can have other types of transistors instead of IGBTs.

[0032] Under the control of motor control device 90, motors 50 and 51 are driven by three-phase alternating current. Current sensors 60 and 61, which detect the current value of each phase of the three-phase alternating current, are respectively installed between inverter circuits 40 and 41 and motors 50 and 51. Current sensors 60 and 61 notify the microcontroller 1 and ASIC 2 of the current value.

[0033] As an example, motor 50 is used to drive the wheels (front or rear wheels) 53, 54 of the vehicle. Motor 50 is connected to differential gear 52 via drive shaft 55. Differential gear 52 transmits the torque of motor 50 to wheels 53, 54 as a driving force corresponding to a reduction ratio specific to the vehicle type. Additionally, motor 51 is used, for example, to generate electricity. Note that the number of motors installed in a vehicle is not limited.

[0034] Accelerator sensor 30 detects the amount of operation of the vehicle's accelerator pedal and outputs the detection value to ECU 3. Brake sensor 31 detects the amount of operation of the vehicle's brake pedal and outputs the detection value to ECU 3.

[0035] ECU 3 is the computer device that typically controls the vehicle. ECU 3 calculates the driving force requested by the vehicle (hereinafter referred to as "requested driving force") based on factors such as the amount of input to the accelerator pedal and the brake pedal. ECU 3 then notifies microcontroller 1 of the requested driving force.

[0036] The microcontroller 1 includes a CPU 10 (as an example of a processor), a read-only memory (ROM) 11, a random access memory (RAM) 12, memories 13 and 14, a communication port 15, and a hardware interface unit (HW-INF) 16. The CPU 10 is electrically connected to the ROM 11, RAM 12, memories 13 and 14, communication port 15, and HW-INF 16 via a bus 19, allowing signals to be input to and output from each other.

[0037] ROM 11 stores the program used to drive CPU 10. RAM 12 functions as the working memory of CPU 10. Communication port 15 is used to communicate with ASIC 2. HW-INF 16 receives the current values ​​of the three-phase AC current from current sensors 60 and 61. HW-INF 16 notifies ASIC 2 of the current values ​​via CPU 10 or communication port 15.

[0038] Memory 13 is an example of a second storage unit, and stores parameters (hereinafter referred to as "vehicle type parameters") 130 related to the vehicle type of the vehicle on which the motor control device 90 is installed. Examples of vehicle type parameters 130 include the reduction ratio of the differential gear 52 connected to the motor 50 or values ​​related to the output performance of the motors 50, 51. As described above, vehicle type parameters 130 are parameters specific to the vehicle type of the vehicle on which the motor control device 90 is installed.

[0039] Memory 14 is an example of a first storage unit and stores feature mapping data 140 related to the drive control of each of the motors 50, 51. Feature mapping data 140 is an example of feature data. Feature mapping data 140 includes, for example, rotational speed-torque mapping data indicating the correlation between the requested rotational speed and torque (hereinafter referred to as "requested rotational speed" and "requested torque") of the motors 50, 51, and torque-current mapping data indicating the correlation between the requested torque and the current command value of the three-phase current.

[0040] Memory 13 and 14 are non-volatile memories such as flash memory. When manufacturing the motor control device 90, a vehicle type parameter 130, determined by the vehicle type of the vehicle to which the motor control device 90 is installed, is written to memory 13, and feature mapping data 140 corresponding to one or more vehicle types is written to memory 14.

[0041] The CPU 10 reads the program from the ROM 11 and operates according to the program. The CPU 10 receives the requested driving force from the ECU 3 and performs calculations related to the drive control of the motors 50, 51 corresponding to the type of vehicle on which the motor control device 90 is installed, based on the vehicle type parameter 130 and the feature mapping data 140, so that the requested driving force is satisfied.

[0042] In the computational processing, CPU 10 calculates the current command value for each of motors 50 and 51 based on vehicle type parameter 130 and feature mapping data 140 according to the requested driving force, and calculates the voltage command value for each of motors 50 and 51 based on the current command value and the current values ​​obtained from current sensors 60 and 61. Furthermore, CPU 10 calculates the on / off timing (hereinafter referred to as "on / off timing") to determine the duty cycle of the PWM signal based on the voltage command value. CPU 10 notifies ASIC 2 of the on / off timing via communication port 15. The on / off timing is an example of the result of the computational processing. Details of the computational processing will be described later.

[0043] ASIC 2 is an example of a drive circuit and includes a monitoring unit 20, an arithmetic unit 21, and an output unit 22. The output unit 22 executes drive processing for each of the motors 50 and 51 based on the results of the arithmetic processing by the CPU 10. The output unit 22 receives on / off timing notifications from the CPU 10 via communication port 15. The output unit 22 generates PWM signals according to the on / off timings and outputs the PWM signals to the inverter circuits 40 and 41.

[0044] The monitoring unit 20 receives notifications from the ECU 3 regarding the normality of the CPU 10. The ECU 3 monitors whether the CPU 10 is operating normally. For example, when the CPU 10 is operating normally, the monitoring unit 20 generates a pulse signal with a predetermined frequency as input from the clock signal received from the oscillator (not shown) and sends the pulse signal to the ECU 3. The ECU 3 determines the normality of the pulse signal received from the CPU 10. When the ECU 3 detects, for example, a stop in the pulse signal or an abnormality in the frequency of the pulse signal, the ECU 3 determines that an abnormality has occurred in the CPU 10.

[0045] The monitoring unit 20 determines whether an anomaly has occurred in the CPU 10 based on the notification. When the monitoring unit 20 determines that an anomaly has occurred in the CPU 10, the monitoring unit 20's instruction processing unit 21 and output unit 22 execute fail-safe operations.

[0046] When the arithmetic unit 21 receives a fail-safe operation instruction from the monitoring unit 20, the arithmetic unit 21 performs the aforementioned arithmetic processing on behalf of the CPU 10. In this case, the arithmetic unit 21 retrieves the vehicle type parameter 130 and feature mapping data 140 from the memories 13 and 14, respectively. At this time, the arithmetic unit 21 accesses the memories 13 and 14 via the communication port 15 and reads the vehicle type parameter 130 and feature mapping data 140 from the memories 13 and 14, respectively. In addition, the arithmetic unit 21 obtains the current value of each phase of the three-phase AC current from the current sensors 60 and 61.

[0047] The arithmetic unit 21 performs arithmetic processing related to the drive control of the vehicle type corresponding to the vehicle on which the motor control device 90 is installed, in the same manner as the CPU 10 under normal conditions, based on the vehicle type parameter 130 obtained from the memory 13 and the feature mapping data 140 obtained from the memory 14.

[0048] Output unit 22 receives on / off timing notifications from arithmetic unit 21, which represents CPU 10. Output unit 22 generates a PWM signal based on the on / off timing and outputs the PWM signal to inverter circuits 40 and 41, just as it would be under normal CPU 10 conditions. This implements a fail-safe function in case of an abnormality occurring in CPU 10.

[0049] In this example, memories 13 and 14 are located internally to microcontroller 1, but they could also be located externally to microcontroller 1 and ASIC 2. In this case, CPU 10 and ASIC 2 could access memories 13 and 14 via, for example, a separate bus. Furthermore, vehicle type parameters 130 and feature mapping data 140 could be stored in a common non-volatile memory. In this case, the storage areas for feature mapping data 140 and vehicle type parameters 130 in the memory are examples of the first and second storage units, respectively.

[0050] Examples of vehicle type parameters and feature mapping data

[0051] Next, the vehicle type parameter 130 and feature mapping data 140 will be described. The rotational speed-torque mapping data and torque-current mapping data applicable to the drive control of motors 50 and 51 differ according to the specifications of each vehicle type. Therefore, the CPU 10 and the arithmetic unit 21 obtain the rotational speed-torque mapping data and torque-current mapping data corresponding to the vehicle type of the vehicle on which the motor control device 90 is mounted, based on the vehicle type parameter 130, from the feature mapping data 140, and use the obtained mapping data for computational processing. The rotational speed-torque mapping data and torque-current mapping data when the vehicle type parameter 130 is the reduction ratio of the differential gear 52 will be described as an example below.

[0052] Figure 2 This is a diagram illustrating example rotational speed-torque mapping data Pa, Pb, Pc corresponding to multiple reduction ratios Ka, Kb, Kc of differential gear 52, respectively. The reduction ratios differ for each vehicle type. The rotational speed-torque mapping data Pa, Pb, Pc indicate the correlation between the rotational speed and torque of motors 50, 51. The rotational speed-torque mapping data Pa, Pb, Pc may differ for each of motors 50, 51, or they may be common to motors 50, 51.

[0053] For example, based on the ratios of reduction ratios Ka, Kb, and Kc, the rotational speed-torque mapping data Pa, Pb, and Pc have similar relationships. For a given rotational speed, in the rotational speed-torque mapping data Pa, corresponding to reduction ratio Ka, the rotational speed-torque mapping data Pa shows the highest torque, and the rotational speed-torque mapping data Pc corresponding to reduction ratio Kc shows the lowest torque.

[0054] The CPU 10 and the arithmetic unit 21 perform calculations using the rotational speed-torque mapping data Pa, Pb, and Pc corresponding to the reduction ratios Ka, Kb, and Kc indicated by the vehicle type parameter 130. For example, when the vehicle type parameter 130 indicates a reduction ratio Kc, the CPU 10 and the arithmetic unit 21 perform calculations using the rotational speed-torque mapping data Pc corresponding to the reduction ratio Kc. In this case, when the rotational speed satisfying the request for driving force from the ECU 3 to the CPU 10 and the arithmetic unit 21 is N, the CPU 10 and the arithmetic unit 21 calculate the requested torque T corresponding to the rotational speed N based on the rotational speed-torque mapping data Pc.

[0055] Figure 3This is a diagram illustrating example torque-current mapping data Qa, Qb, Qc corresponding to reduction ratios Ka, Kb, Kc of differential gear 52, respectively. The reduction ratios differ for each vehicle type. The torque-current mapping data Qa, Qb, Qc indicate the correlation between the current command value and the requested torque of motors 50, 51. The torque-current mapping data Qa, Qb, Qc may be different for each of motors 50, 51, or they may be common to motors 50, 51.

[0056] For example, based on the ratios of reduction ratios Ka, Kb, and Kc, the torque-current mapping data Qa, Qb, and Qc have similar relationships with each other. For a given requested torque, in the torque-current mapping data Qa, Qb, and Qc, the torque-current mapping data Qc corresponding to reduction ratio Kc displays the highest current command value, and the torque-current mapping data Qa corresponding to reduction ratio Ka displays the lowest current command value.

[0057] The CPU 10 and the arithmetic unit 21 perform calculations using torque-current mapping data Qa, Qb, and Qc corresponding to the reduction ratios Ka, Kb, and Kc indicated by the vehicle type parameter 130. For example, when the vehicle type parameter 130 indicates a reduction ratio Kc, the CPU 10 and the arithmetic unit 21 perform calculations using the torque-current mapping data Qc corresponding to the reduction ratio Kc. In this case, when the requested torque is T, the CPU 10 and the arithmetic unit 21 calculate the current command value I corresponding to the requested torque T based on the torque-current mapping data Qc.

[0058] Next, a method for obtaining rotational speed-torque mapping data and torque-current mapping data corresponding to the vehicle type of the vehicle on which the motor control device 90 is installed will be described.

[0059] Figure 4 This diagram illustrates an example of a method for obtaining rotational speed-torque mapping data Pc and torque-current mapping data Qc corresponding to the vehicle type of the vehicle on which the motor control device 90 is installed. In this example, it is assumed that the motor control device 90 is installed on a vehicle of a vehicle type with a reduction ratio of Kc. Therefore, the memory 13 stores, for example, the reduction ratio Kc as a vehicle type parameter 130 associated with the vehicle type on which the motor control device 90 is installed.

[0060] Furthermore, the feature mapping data 140 stored in memory 14 includes only the rotational speed-torque mapping data Pa corresponding to the reduction ratio Ka from the rotational speed-torque mapping data Pa, Pb, Pc, and only the torque-current mapping data Qa corresponding to the reduction ratio Ka from the torque-current mapping data Qa, Qb, Qc. In other words, memory 14 stores torque-current mapping data Qa corresponding to a different vehicle type than the vehicle on which the motor control device 90 is installed.

[0061] If the CPU 10 and the arithmetic unit 21 use the rotational speed-torque mapping data Pa and the torque-current mapping data Qa for processing, the motors 50 and 51 cannot be driven and controlled normally because the rotational speed-torque mapping data Pa and the torque-current mapping data Qa are not applicable to the characteristics of the vehicle type on which the motor control device 90 is installed. As a result, the fail-safe function cannot be properly implemented.

[0062] To this end, CPU 10 and arithmetic unit 21 retrieve the reduction ratio Kc and rotational speed-torque mapping data Pa from memories 13 and 14, respectively, and correct the rotational speed-torque mapping data Pa based on the reduction ratio Kc to obtain rotational speed-torque mapping data Pc corresponding to the reduction ratio Kc. For example, CPU 10 and arithmetic unit 21 multiply the rotational speed of the rotational speed-torque mapping data Pa by a constant based on the ratio of reduction ratio Ka to reduction ratio Kc to obtain rotational speed-torque mapping data Pc corresponding to reduction ratio Kc. Here, CPU 10 and arithmetic unit 21 pre-set the reduction ratio Ka corresponding to the rotational speed-torque mapping data Pa to a fixed value.

[0063] Furthermore, the CPU 10 and the arithmetic unit 21 retrieve torque-current mapping data Qa from the memory 14 and correct the torque-current mapping data Qa based on the reduction ratio Kc to obtain torque-current mapping data Qc corresponding to the reduction ratio Kc. For example, the CPU 10 and the arithmetic unit 21 multiply the current command value of the torque-current mapping data Qa by a constant based on the ratio of the reduction ratio Ka to the reduction ratio Kc to obtain torque-current mapping data Qc corresponding to the reduction ratio Kc.

[0064] In this way, the CPU 10 and the arithmetic unit 21 correct the rotational speed-torque mapping data Pa and the torque-current mapping data Qa based on the vehicle type parameter 130, so that the rotational speed-torque mapping data Pa and the torque-current mapping data Qa correspond to the vehicle type of the vehicle on which the motor control device 90 is installed, and use the corrected mapping data for arithmetic processing.

[0065] Figure 5This is a diagram illustrating another example of a method for obtaining rotational speed-torque mapping data Pa, Pb, Pc and torque-current mapping data Qa, Qb, Qc. In this example, it is assumed that the motor control device 90 is installed on a vehicle of a vehicle type with a reduction ratio of Kc. Therefore, the memory 13 stores, for example, the reduction ratio Kc as a vehicle type parameter 130 associated with the vehicle type on which the motor control device 90 is installed.

[0066] Furthermore, the feature mapping data 140 stored in memory 14 includes rotational speed-torque mapping data Pa, Pb, Pc and torque-current mapping data Qa, Qb, Qc, respectively, corresponding to reduction ratios Ka, Kb, Kc associated with various vehicle types. The feature mapping data 140 also includes rotational speed-torque mapping data Pa, Pb and torque-current mapping data Qa, Qb, but not the vehicle type on which the motor control device 90 is mounted. In other words, memory 14 stores feature mapping data 140 corresponding to the various vehicle types.

[0067] The CPU 10 and the arithmetic unit 21 obtain the reduction ratio Kc from the memory 13. The CPU 10 and the arithmetic unit 21 select and retrieve only the rotational speed-torque mapping data Pc corresponding to the reduction ratio Kc from the rotational speed-torque mapping data Pa, Pb, and Pc stored in the memory 14. Specifically, the CPU 10 and the ASIC 2 read the rotational speed-torque mapping data Pc from the storage area of ​​the memory 14, for example, the storage area corresponding to the reduction ratio Kc.

[0068] Furthermore, the CPU 10 and the arithmetic unit 21 select and retrieve only the torque-current mapping data Qc corresponding to the reduction ratio Kc from the torque-current mapping data Qa, Qb, and Qc stored in the memory 14. Specifically, the CPU 10 and the arithmetic unit 21 read the torque-current mapping data Qc from the storage area of ​​the memory 14, for example, the storage area corresponding to the reduction ratio Kc.

[0069] As described above, the CPU 10 and the arithmetic unit 21 read rotational speed-torque mapping data Pc and torque-current mapping data Qc from the memory 14 based on the vehicle type parameter 130, which correspond to the vehicle type of the vehicle on which the motor control device 90 is installed, and use the read mapping data for arithmetic processing.

[0070] In this way, the CPU 10 and the arithmetic unit 21 can acquire rotational speed-torque mapping data Pc and torque-current mapping data Qc corresponding to the reduction ratio Kc of the vehicle type on which the motor control device 90 is mounted. Therefore, the CPU 10 and the arithmetic unit 21 can calculate the appropriate requested torque and current command values ​​corresponding to the reduction ratio Kc.

[0071] In addition, Figure 4 In this example, the capacity of memory 14 can be reduced because the amount of feature map data 140 stored in memory 14 is less than that in [the context of the example]. Figure 5 The amount of data in the example case. On the other hand, in Figure 5 In the example case, with Figure 4 Unlike the example, the CPU 10 and the arithmetic unit 21 do not need to perform correction processing of the rotational speed-torque mapping data Pa and the torque-current mapping data Qa, thereby reducing the computational processing load.

[0072] Operation example of motor control equipment

[0073] Figure 6 This is a flowchart illustrating an example of the operation of CPU 10. Steps St2 to St8 described below are examples of computational processing related to the drive control of motors 50, 51 corresponding to the vehicle type on which the motor control device 90 is mounted.

[0074] The CPU 10 receives a notification requesting driving force from the ECU 3 (step St1). Next, the CPU 10 retrieves the vehicle type parameter 130 from the memory 13 (step St2).

[0075] Next, the CPU 10 first reads the rotational speed-torque mapping data from the feature mapping data 140 in the memory 14 (step St3). Then, the CPU 10 calculates the requested torque corresponding to the rotational speed of the motors 50 and 51 that satisfy the requested driving force based on the vehicle type parameter 130 and the rotational speed-torque mapping data (step St4).

[0076] At this time, CPU 10, based on the reference... Figure 4 or Figure 5 The described acquisition method uses vehicle type parameter 130 to obtain rotational speed-torque mapping data corresponding to the vehicle type of the vehicle on which the motor control device 90 is installed. CPU 10 obtains the requested torque corresponding to the rotational speed of motors 50 and 51 from the rotational speed-torque mapping data corresponding to the vehicle type of the vehicle on which the motor control device 90 is installed.

[0077] Next, the CPU 10 reads the torque-current mapping data from the feature mapping data 140 in the memory 14 (step St5). Then, the CPU 10 calculates the current command value of the three-phase AC current that satisfies the requested torque based on the vehicle type parameter 130 and the torque-current mapping data (step St6).

[0078] At this time, CPU 10, based on the reference... Figure 4 or Figure 5 The described acquisition method uses vehicle type parameter 130 to obtain torque-current mapping data corresponding to the vehicle type of the vehicle on which the motor control device 90 is installed. Furthermore, the CPU 10 obtains the current command value of the three-phase AC current that satisfies the requested torque from the torque-current mapping data corresponding to the vehicle type of the vehicle on which the motor control device 90 is installed.

[0079] Next, CPU 10 calculates the voltage command values ​​for motors 50 and 51 based on the current command value (step St7). At this time, CPU 10 obtains the three-phase AC current values ​​from current sensors 60 and 61 via HW-INF 16. CPU 10 determines the current command value, for example, based on the difference between the current command value and the current value of the current sensor using PI control.

[0080] Next, CPU 10 performs the duty cycle calculation of the PWM signal based on the voltage command value (step St8). At this time, as indicated by reference numeral G in the attached diagram, CPU 10 generates a carrier signal that varies as a triangular waveform on the time axis and compares the voltage command value, which varies as a sinusoidal waveform, with the signal value of the carrier signal. The carrier signal is used to determine the on / off timing of the PWM signal. When the signal value of the carrier signal is equal to or greater than the voltage command value, the PWM signal is turned off, and when the signal value of the carrier signal is less than the voltage command value, the PWM signal is turned on. CPU 10 calculates the on-time Ton and the off-time Toff of the PWM signal. The duty cycle of the PWM signal is determined by the times Ton and Toff.

[0081] In this way, the CPU 10 performs computational processing related to the drive control of motors 50, 51 corresponding to the vehicle type of the vehicle on which the motor control device 90 is installed, based on the vehicle type parameter 130 and feature mapping data 140.

[0082] Next, CPU 10 notifies the output unit 22 of ASIC 2 of the on / off timings, namely times Ton and Toff (step St9), as the result of the computation, via communication port 15. In this way, CPU 10 is operated.

[0083] Figure 7 This is a flowchart illustrating an example of the operation of ASIC 2. Steps St15 to St21 described below are examples of computational processing related to the drive control of motors 50 and 51 corresponding to a vehicle type on which the motor control device 90 is mounted. Furthermore, step St13 described below is an example of the drive processing of motors 50 and 51 of a vehicle on which the motor control device 90 is mounted.

[0084] The monitoring unit 20 of ASIC 2 determines whether the operation of CPU 10 is normal based on the notification from ECU 3 (step St11). The monitoring unit 20 can directly determine the normality of CPU 10 by communicating with CPU 10, without going through ECU 3.

[0085] When CPU 10 operates normally (Yes in step St11), output unit 22 receives on / off timing notification from CPU 10 (step St12). Then, output unit 22 generates a PWM signal based on the on / off timing (see...). Figure 6 (Ref. G in the attached figure) and output the PWM signal to the inverter circuits 40 and 41 (step St13). As described above, when the CPU 10 is operating normally, the ASIC 2 performs the generation and output processing of the PWM signal based on the result of the CPU 10's calculation, regardless of the type of vehicle, and is not controlled by the motors 50 and 51.

[0086] Alternatively, when the CPU 10 malfunctions (No in step St11), ASIC 2 performs the following steps St14 to St21 on behalf of the CPU 10 to implement the fail-safe function.

[0087] The arithmetic unit 21 receives a notification requesting driving force from the ECU 3 (step St14). Next, the ASIC 2 retrieves the vehicle type parameter 130 from the memory 13 (step St15).

[0088] Next, the arithmetic unit 21 first reads the rotational speed-torque mapping data from the feature mapping data 140 in the memory 14 (step St16). Then, the arithmetic unit 21 calculates the requested torque corresponding to the rotational speed of the motors 50 and 51 that satisfy the requested driving force based on the vehicle type parameter 130 and the rotational speed-torque mapping data (step St17).

[0089] At this time, the arithmetic unit 21, according to the reference... Figure 4 or Figure 5 The described acquisition method uses vehicle type parameter 130 to obtain rotational speed-torque mapping data corresponding to the vehicle type of the vehicle on which the motor control device 90 is installed. Furthermore, the calculation unit 21 obtains the requested torque corresponding to the rotational speed of motors 50 and 51 from the rotational speed-torque mapping data corresponding to the vehicle type of the vehicle on which the motor control device 90 is installed.

[0090] Next, the arithmetic unit 21 reads the torque-current mapping data from the feature mapping data 140 in the memory 14 (step St18). Then, the arithmetic unit 21 calculates the current command value of the three-phase AC current that satisfies the requested torque based on the vehicle type parameter 130 and the torque-current mapping data (step St19).

[0091] At this time, the arithmetic unit 21, according to the reference... Figure 4 or Figure 5 The described acquisition method obtains torque-current mapping data corresponding to the vehicle type of the vehicle on which the motor control device 90 is installed, based on the vehicle type parameter 130. Furthermore, the arithmetic unit 21 obtains the current command value of the three-phase AC current that satisfies the requested torque from the torque-current mapping data corresponding to the vehicle type of the vehicle on which the motor control device 90 is installed.

[0092] Next, the arithmetic unit 21 calculates the voltage command values ​​for motors 50 and 51 based on the current command value (step St20). At this time, the arithmetic unit 21 obtains the current values ​​of the three-phase AC current from current sensors 60 and 61. The arithmetic unit 21 determines the current command value, for example, based on the difference between the current command value and the current value of the current sensor using PI control.

[0093] Next, the arithmetic unit 21 performs the duty cycle operation of the PWM signal according to the voltage command value (step St21). At this time, as referred to Figure 6 As indicated by reference numeral G in the accompanying drawings, the arithmetic unit 21 compares the signal value of the carrier signal with the voltage command value to calculate the time Ton when the PWM signal is turned on and the time Toff when the PWM signal is turned off, as the on / off timing.

[0094] Next, the arithmetic unit 21 generates a PWM signal based on the on / off timing and outputs the PWM signal to the inverter circuits 40 and 41 (step St13).

[0095] As described above, when the CPU 10 malfunctions, the ASIC 2 performs arithmetic processing corresponding to the type of the vehicle on which the motor control device 90 is installed, based on the vehicle type parameter 130 and feature mapping data 140 read from the memories 13 and 14, respectively.

[0096] Therefore, through the fail-safe operation of ASIC 2, even if an anomaly occurs in CPU 10, the motor control device 90 can continue to drive the motors 50 and 51 corresponding to the characteristics of the vehicle type on which the motor control device 90 is installed. Furthermore, since the memories 13 and 14 are located external to ASIC 2, the increase in device cost is suppressed. Thus, the motor control device 90 can suppress the increase in device cost and appropriately implement fail-safe functions in response to vehicle type.

[0097] The above embodiments are examples of preferred embodiments of the present invention. Note that the present invention is not limited to the described embodiments, and various modifications can be made without departing from the spirit of the invention.

Claims

1. A motor control device, characterized in that... include: A first storage unit is configured to store feature data related to the drive control of motors for various vehicle types; A second storage unit is configured to store vehicle type parameters related to a predetermined vehicle type, wherein the vehicle type parameters are the reduction ratio of a differential gear connected to the motor. A processor configured to perform computational processing related to the drive control corresponding to the predetermined vehicle type based on the vehicle type parameters and the feature data; and A drive circuit configured to perform drive processing for the motor of the vehicle of the predetermined vehicle type based on the result of the computational processing. The drive circuit is configured to: when an exception occurs in the processor, read the feature data from the first storage unit and the vehicle type parameter from the second storage unit, and perform arithmetic processing related to drive control corresponding to the predetermined vehicle type based on the vehicle type parameter and the feature data.

2. The motor control device according to claim 1, characterized in that: The first storage unit is configured to store feature data corresponding to a different vehicle type than the predetermined vehicle type; and The drive circuit is configured to: when an anomaly occurs in the processor, correct the feature data based on the vehicle type parameter so that the feature data corresponds to the predetermined vehicle type, and use the corrected feature data for the computational processing.

3. The motor control device according to claim 1 or 2, characterized in that: The drive circuit is configured to: read feature data corresponding to the predetermined vehicle type among the multiple vehicle types from the first storage unit based on the vehicle type parameter, and use the feature data for the computational processing.

4. The motor control device according to claim 1 or 2, characterized in that, The feature data includes the correlation between the motor's rotational speed and torque.

5. The motor control device according to claim 1 or 2, characterized in that, The feature data includes the correlation between the motor's torque and current values.

6. The motor control device according to claim 1 or 2, characterized in that, The drive circuit is configured to receive a notification relating to the normality of the processor, and the drive circuit is configured to determine, based on the notification, whether an anomaly has occurred in the processor.

7. A motor control method, characterized in that... include: The drive circuit determines whether an anomaly has occurred in the processor, wherein the processor is configured to perform arithmetic processing related to the drive control of a predetermined vehicle type based on feature data related to the drive control of motors of various vehicle types and vehicle type parameters related to a predetermined vehicle type, wherein the vehicle type parameters are the reduction ratio of the differential gear connected to the motor. When the drive circuit determines that an anomaly has occurred in the processor, the drive circuit reads the feature data from a first storage unit and the vehicle type parameter from a second storage unit, wherein the first storage unit is configured to store the feature data related to the drive control of the motors of the various vehicle types, and the second storage unit is configured to store the vehicle type parameter related to the predetermined vehicle type; and The drive circuit performs calculations related to drive control corresponding to the predetermined vehicle type based on the vehicle type parameters and the feature data.

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