Rotary electric machine control device

Abstract

This rotary electric machine control device (15) controls drive of a rotary electric machine (80), and comprises a control unit (120, 220) and a driver drive unit (160, 170, 260, 270). The control unit (120, 220) calculates a drive command value for the rotary electric machine (80). The driver drive unit (160, 170, 260, 270) has a signal output unit (166) that outputs a drive signal corresponding to the drive command value to a driver circuit (150, 155, 250, 255) that switches energization of the rotary electric machine (80), and a storage unit (162) that can store the drive command value acquired from the control unit (120, 220). The driver drive unit (160, 170, 260, 270) acquires the drive command value from the control unit (120, 220) by digital communication.

Description

Rotating electrical machine control device Cross-reference of related applications

[0001] This application is based on Patent Application No. 2024-205348, filed on November 26, 2024, and its contents are incorporated herein by reference.

[0002] This disclosure relates to a control device for rotating electric machines.

[0003] Conventionally, rotating electric machine control devices for controlling the drive of rotating electric machines are known. For example, in Patent Document 1, two winding assemblies, two drive circuits, and two control units are provided.

[0004] Patent No. 6769328

[0005] As shown in Patent Document 1, providing multiple control units improves the continuity of operation after a failure occurs. On the other hand, providing multiple control units increases the number of components and wiring mounted on the circuit board. Also, if communication is digitized and communication lines are shared in order to reduce the number of wires, there is a risk of communication delay compared to analog communication. The object of this disclosure is to provide a rotating electric machine control device that can appropriately control the drive of a rotating electric machine.

[0006] The rotating electric machine control device of this disclosure controls the drive of a rotating electric machine and comprises a control unit and a driver drive unit. The control unit calculates a drive command value for the rotating electric machine. The driver drive unit has a signal output unit that outputs a drive signal corresponding to the drive command value to a driver circuit that switches the power supply to the rotating electric machine, and a storage unit that can store the drive command value acquired from the control unit, and acquires the drive command value from the control unit via digital communication. This enables appropriate control of the drive of the rotating electric machine.

[0007] The above-mentioned objectives and other objectives, features and advantages of this disclosure will become clearer with reference to the attached drawings and the detailed description below. The drawings are as follows: Figure 1 is a schematic configuration diagram showing an electric power steering device according to the first embodiment; Figure 2 is a block diagram showing an ECU according to the first embodiment; Figure 3 is a block diagram showing a microcontroller and pre-driver IC according to the first embodiment; Figure 4A is a block diagram showing an example of digital transmission of drive command values; Figure 4B is a block diagram showing an example of analog transmission of drive command values; Figure 5 is a time chart illustrating the timing of new duty cycle reflection by analog and digital communication; Figure 6 is a time chart illustrating duty cycle update according to the first embodiment; Figure 7 is a flowchart illustrating abnormality monitoring processing according to the first embodiment; Figure 8 is a time chart illustrating duty cycle update according to the second embodiment; Figure 9 is a time chart illustrating duty cycle update according to the third embodiment; Figure 10 is a time chart illustrating duty cycle update according to the fourth embodiment; and Figure 11 is a time chart illustrating duty cycle update according to the fourth embodiment.

[0008] The rotating electric machine control device according to this disclosure will be described below with reference to the drawings. In the following embodiments, substantially identical components will be denoted by the same reference numerals and their descriptions will be omitted.

[0009] (First Embodiment) The first embodiment is shown in Figures 1 to 7. As shown in Figure 1, the drive unit 10 comprises a motor 80 as a rotating electric machine and an ECU 15 as a rotating electric machine control unit, and is applied to an electric power steering device 8, which is a steering device for assisting the steering operation of a vehicle. Figure 1 shows the overall configuration of a steering system 90 equipped with an electric power steering device 8. The steering system 90 comprises steering members such as a steering wheel 91, a steering shaft 92, a pinion gear 96, a rack shaft 97, wheels 98, and an electric power steering device 8.

[0010] The steering wheel 91 is connected to the steering shaft 92. The steering shaft 92 is equipped with a torque sensor 93 for detecting steering torque. A pinion gear 96 is provided at the end of the steering shaft 92. The pinion gear 96 meshes with the rack shaft 97. A pair of wheels 98 are connected to both ends of the rack shaft 97 via tie rods or the like.

[0011] When the driver rotates the steering wheel 91, the steering shaft 92 connected to the steering wheel 91 rotates. The rotational motion of the steering shaft 92 is converted into linear motion of the rack shaft 97 by the pinion gear 96. The pair of wheels 98 are steered to an angle corresponding to the displacement of the rack shaft 97.

[0012] The electric power steering system 8 includes a drive unit 10 and a reduction gear 89, etc., which serves as a power transmission unit that reduces the rotation of the motor 80 and transmits it to the rack shaft 97. The electric power steering system 8 in this embodiment is a so-called "rack assist type," but it may also be a so-called "column assist type" that transmits the rotation of the motor 80 to the steering shaft 92.

[0013] The drive unit 10 has an ECU 15 integrally mounted on one axial side of the motor 80, making it a so-called "mechatronics-integrated" unit, but it may be a separate unit. The ECU 15 has a connector 16, which connects to the vehicle power supply 100, 200, the vehicle communication network 300, and the torque sensor 93. The vehicle communication network 300 is, for example, a CAN (Controller Area Network), and although it is written as "CAN" in the figure, a communication method other than CAN may be used.

[0014] As shown in Figure 2, the motor 80 is, for example, a three-phase brushless motor and has motor windings 180, 185, 280, and 285. The motor 80 outputs part or all of the torque required for steering and is driven by power supplied from power sources 100 and 200, causing the reduction gear 89 (see Figure 1) to rotate in forward and reverse directions.

[0015] In this embodiment, the components on the upper side of the page indicated by the dashed line in Figure 2 are supplied with power from power supply 100, and the components on the lower side of the page indicated by the dashed line are supplied with power from power supply 200. In other words, the drive device 10 in this embodiment is a "two-system power supply" that is supplied with power from two power supplies 100 and 200. In this embodiment, the combination of components supplied with power from power supply 100 is called the first system, and the combination of components supplied with power from power supply 200 is called the second system. Components related to the first system are numbered in the 100s, and components related to the second system are numbered in the 200s. Components with the same or similar configurations in the first and second systems are numbered so that the last two digits are the same, and explanations are omitted as appropriate.

[0016] The ECU 15 includes microcontrollers 120 and 220, driver circuits 150, 155, 250, and 255, and pre-driver ICs 160, 170, 260, and 270, etc. Microcontrollers 120 and 220 each contain internally a CPU, ROM, RAM, I / O, and bus lines connecting these components (not shown). Each process in microcontrollers 120 and 220 may be software processing by executing a program pre-stored in a physical memory device such as ROM (i.e., a readable non-temporary tangible recording medium) using the CPU, or it may be hardware processing using dedicated electronic circuits.

[0017] The microcontrollers 120 and 220 are connected via an isolator (not shown) to enable communication between them. In this embodiment, the microcontrollers 120 and 220 are configured similarly, but their performance and configuration details may differ.

[0018] Microcontroller 120 is powered by power supply IC 131, and microcontroller 220 is powered by power supply IC 231. Power supply ICs 131 and 231 are power management ICs (PMICs).

[0019] External communication units 132 and 232 are connected to the vehicle communication network 300 and acquire vehicle signals from the vehicle communication network 300. Oscillators 133 and 233 are clock sources such as crystal or ceramic oscillators.

[0020] Driver circuits 150, 155, 250, and 255 are provided corresponding to motor windings 180, 185, 280, and 285, respectively, and six switching elements (not shown) are connected in a bridge configuration. The switching element is, for example, a MOSFET, but it may also be an IGBT, a bipolar transistor, or the like.

[0021] Pre-driver ICs 160, 170, 260, and 270 are provided corresponding to driver circuits 150, 155, 250, and 255. Pre-driver ICs 160 and 170 are provided to be digitally communicable with microcomputer 120, and pre-driver ICs 260 and 270 are provided to be digitally communicable with microcomputer 220. In this embodiment, the communication between the microcomputer and the pre-driver IC is SPI communication, but it may be a communication format other than SPI communication, such as I2C.

[0022] The communication lines connecting pre-driver ICs 160, 170, 260, and 270 and microcomputers 120 and 220 are connected by inter-system connection line 25. An isolator (not shown) is provided in inter-system connection line 25. By providing the isolator, information transmission between systems is possible while maintaining the potential difference between the first system and the second system. By digitizing the communication between the control unit and the pre-driver IC and providing inter-system connection line 25, for example, even if an abnormality occurs in one arithmetic core, commands from other normal arithmetic cores to all pre-driver ICs 160, 170, 260, and 270 can be continued.

[0023] The details of the microcomputer and the pre-driver IC will be described based on FIG. 3. Hereinafter, microcomputer 120 and pre-driver IC 160 will be described as an example, and microcomputer 220 and pre-driver ICs 170, 260, and 270 are substantially the same, so the description thereof will be omitted.

[0024] The microcomputer 120 includes an arithmetic unit 121, a communication unit 125, a timer unit 126, a permission signal output unit 127, and the like. The arithmetic unit 121 is an arithmetic core that performs various arithmetic processes, and generates a drive command value for controlling the drive of the motor 80 based on detection values from current sensors, position sensors, torque sensors, and the like. The arithmetic unit 121 may be provided individually or commonly for the pre-driver ICs 160 and 170 provided corresponding to the microcomputer 120.

[0025] The drive command value is a duty command value that, for example, PWM-controls the on / off operation of the switching elements constituting the driver circuit. Specifically, the duty command value is a value that commands the duty ratio, which is the ratio of the on-time to the off-time of the switching element, and is calculated, for example, by current feedback control.

[0026] The communication unit 125 transmits and receives signals to and from the pre-driver IC 160 by digital communication. The timer unit 126 transmits a timer signal to the pre-driver IC 160. The timer signal in this embodiment is a clock signal (denoted as "CLK" in the figure). The permission signal output unit 127 outputs an enable signal (denoted as "enable" in the figure) that permits the output of the drive signal from the pre-driver IC 160 to the driver circuit 150 to the pre-driver IC 160.

[0027] The pre-driver IC 160 includes a communication unit 161, a memory unit 162, an estimation arithmetic unit 163, a duty reflection unit 164, a permission signal input unit 165, a duty output unit 166, an abnormality monitoring unit 168, and the like.

[0028] The communication unit 161 transmits and receives signals to and from the microcomputer 120 by digital communication. In this embodiment, the pre-driver IC 160 acquires the duty command value from the microcomputer 120 by digital communication. The memory unit 162 is configured to be able to hold at least one set of duty command values transmitted from the microcomputer 120.

[0029] The estimation calculation unit 163 calculates a duty cycle command value that interpolates the intermediate timing based on the duty cycle command value acquired from the microcontroller 120. Hereafter, the duty cycle command value acquired from the microcontroller 120 will be referred to as the "acquired duty cycle," and the duty cycle command value calculated by the estimation calculation unit 163 will be referred to as the "interpolated duty cycle." If there is no distinction between the value acquired from the microcontroller 120 and the value calculated by the estimation calculation unit 163, it will simply be referred to as the "duty cycle." In this embodiment, the estimation calculation unit 163 is configured as a hardware circuit, but it may also be configured to calculate the interpolated duty cycle using software calculations.

[0030] The duty cycle reflection unit 164 reflects and holds the acquired or calculated duty cycle at a predetermined timing. The enable signal input unit 165 receives the enable signal output from the enable signal output unit 127. When duty cycle output is permitted by the enable signal, the duty cycle output unit 166 outputs a PWM gate waveform to the driver circuit 150 as a drive signal corresponding to the duty cycle held in the duty cycle reflection unit 164. The abnormality monitoring unit 168 monitors for abnormalities in the pre-driver IC 160 itself, such as communication interruption or power failure.

[0031] As shown in the reference example in Figure 4B, when transmitting duty cycle command values ​​from the microcontroller 120 to the pre-driver IC 160 as analog signals, in addition to the digital communication lines used for reading driver abnormal status, etc. (four lines in the example in Figure 4B), it is necessary to separately provide wiring for analog communication according to the number of switching elements (for example, six) that make up the driver circuit 150. As shown in Figure 4A, in this embodiment, the duty cycle command values ​​are transmitted from the microcontroller 120 to the pre-driver IC 160 via digital communication, eliminating the need for wiring for analog communication and thus reducing the number of wires.

[0032] Figure 5 illustrates duty cycle updates, with a common time axis on the horizontal axis. The upper section shows an example of transmitting duty cycle command values ​​via analog communication, and the lower section shows an example of transmitting duty cycle command values ​​via digital communication. In the figure, to distinguish between digital communication content, the subscript "E" is used for digital communication related to reading abnormal status before command calculation, the subscript "A" is used for digital communication related to command transmission, and the subscript "B" is used for communications other than commands, such as duty cycle reflection confirmation and configuration settings after command transmission.

[0033] The microcontroller 120 acquires the detection values ​​of the torque sensor 93, a current sensor (not shown), and a rotation angle sensor at time x1. It also reads information such as abnormal status from the pre-driver IC 160 via digital communication. Between times x2 and x3, the calculation unit 121 calculates duty cycle command values ​​based on the acquired detection values. In the case of analog communication shown in the upper section, once the command calculation is completed at time x3, the pre-driver IC 160 can quickly reflect the new duty cycle.

[0034] On the other hand, in the case of digital communication shown in the lower section, a new duty cycle command value is transmitted between time x3 and time x4, and then communication such as duty cycle reflection confirmation and configuration setting transmission is performed between time x4 and time x5. Therefore, if the new duty cycle is reflected after the completion of one frame of communication, the reflection timing will be delayed compared to analog communication. If the duty cycle reflection timing is delayed, there is a concern that the frequency of duty cycle updates will decrease, and the responsiveness of the motor drive will decrease.

[0035] The duty cycle update process of this embodiment will be explained with reference to Figure 6. In Figure 6, the upper section shows an example of transmitting the duty cycle command value via analog communication, the middle section shows an example of transmitting the duty cycle command value via digital communication, and the lower section shows the synchronization signal. Also, for space reasons, sensor inputs are collectively labeled "In," communication A is labeled "A," communication B is labeled "B," and communication E is labeled "E." In Figure 6, the duty cycle update timings are indicated by dashed lines, labeled N1, N2, etc. from left to right. Furthermore, the duty cycle command value updated at timing N2 is D （Ｎ２） The update timings were indicated with subscripts in this manner. The same applies to the time charts from Figure 8 onwards.

[0036] In this embodiment, the synchronization signal is a clock signal transmitted from the timer unit 126 of the microcontroller 120. The pre-driver IC 160 updates its duty cycle when the synchronization signal switches from L to H. Alternatively, the duty cycle may be updated when the synchronization signal switches from H to L, or it may be updated at both L to H and H to L timings. This allows the duty cycle update timings of multiple pre-driver ICs 160, 170, 260, and 270 to be synchronized.

[0037] As explained in Figure 5, when the duty cycle command value is transmitted from the microcontroller 120 to the pre-driver IC 160 via analog communication, the communication is completed within one duty cycle update cycle CA, and the duty cycle command value generated by calculations within the cycle CA of N1 to N2 can be reflected in the update timing N2.

[0038] On the other hand, when transmitting duty cycle command values ​​from the microcontroller 120 to the pre-driver IC 160 via digital communication, communication is not completed within a single duty cycle update cycle CA. Specifically, at update timing N2, communication A of the duty cycle command value calculated within the cycle CA from N1 to N2 is completed, but subsequent communication B related to duty cycle confirmation, etc., is not completed. It is possible to update the duty cycle command value calculated between N1 and N2 at update timing N2, but the next communication cannot be completed in time, so the duty cycle cannot be updated at update timing N3.

[0039] Therefore, in this embodiment, the duty cycle estimation calculation is performed on the pre-driver IC 160 side, thereby reducing the communication frequency while updating the duty cycle at a frequency similar to that of analog communication. Specifically, in the duty cycle calculation from N1 to N2, the microcontroller 120 determines the duty cycle command value D at timing N2, which is the next update timing. （Ｎ２） Instead, the duty cycle command value D is updated at the next timing N3. （Ｎ３） Perform the calculation.

[0040] The pre-driver IC 160 receives the duty cycle command value D transmitted from the microcontroller 120. （Ｎ３）is stored in the memory unit 162. Further, the estimation calculation unit 163 reads the duty command value D （Ｎ１） stored in the memory unit 162, and uses the duty command values D （Ｎ１） and D （Ｎ３） to estimate and calculate the duty command value D （Ｎ２） . Here, assuming that N1 is the previous time, N2 is the current time, and N3 is the next time, the current value (D （Ｎ２） ) can be regarded as being calculated from the previous value (D （Ｎ１） ) and the next value (D （Ｎ３） ). The estimation calculation of the duty command value D （Ｎ２） is, for example, the average value of the duty command values D （Ｎ１） and D （Ｎ３） , but the details of the calculation, such as linear interpolation, non-linear interpolation, weighted average for multiple times, etc., are not limited.

[0041] In this embodiment, during normal operation, in chronological order, the command calculation in the microcomputer 120 is completed, the command value is received in the pre-driver IC 160, the duty is updated, and the communication frame transmission is completed. The pre-driver IC 160 receives the duty command value from the microcomputer 120 at an update timing corresponding to an update timing earlier than the latest updateable timing after receiving the duty command value from the microcomputer 120. Then, before a series of communications are completed, duty estimation calculation is performed, and at the latest update timing when the duty command value is received, the duty is updated using the interpolated duty calculated by the pre-driver IC 160 from the previous value and the next value. If the calculation of the interpolated duty cannot be completed in time due to communication delay or the like, the previous value is carried over. In FIG. 6, the acquired duty is indicated by a solid-line star mark, and the interpolated duty is indicated by a dashed-line star mark. In this embodiment, by alternately using the acquired duty and the interpolated duty for duty update, it is possible to maintain the duty update frequency while reducing the communication frequency.

[0042] The abnormal monitoring process in the pre-driver IC 160 will be described based on the flowchart of FIG. 8. This process is a process executed by the abnormal monitoring unit 168 at a predetermined period. Hereinafter, the "steps" such as step S101 will be omitted and simply denoted by the symbol "S".

[0043] In S101, the abnormality monitoring unit 168 determines whether or not there is a communication abnormality. If it is determined that there is no communication abnormality (S101: NO), steps S102 and beyond are skipped. In this case, no abnormality action is taken, and normal duty cycle updates continue. If it is determined that there is a communication abnormality (S101: YES), the process proceeds to S102.

[0044] In S102, the abnormality monitoring unit 168 determines whether there is a power supply voltage abnormality, an output duty cycle abnormality, or an internal circuit abnormality. If it is determined that there is no power supply voltage abnormality, output abnormality, or internal circuit abnormality (S102: NO), the process proceeds to S103, the previous value of the duty cycle is retained, and the output of the drive signal continues. If it is determined that there is at least one of the power supply voltage abnormality, output duty cycle abnormality, or internal circuit abnormality (S102: YES), the process proceeds to S104, and the output of the drive signal from the pre-driver CI 60 to the driver circuit 150 is stopped.

[0045] As explained above, the ECU 15 controls the drive of the motor 80 and includes microcontrollers 120 and 220, and pre-driver ICs 160, 170, 260, and 270. Microcontrollers 120 and 220 calculate the duty cycle command value for the motor 80. The following description will focus on microcontroller 120 and pre-driver IC 160, but the same principles apply to microcontroller 120 and pre-driver IC 170, and microcontroller 220 and pre-driver ICs 260 and 270.

[0046] The pre-driver IC 160 has a duty cycle output unit 166 that outputs a drive signal according to the duty cycle command value to the driver circuit 150 that switches the power supply to the motor 80, and a memory unit 162 that can store the duty cycle command value acquired from the microcontroller 120, and acquires the duty cycle command value from the microcontroller 120 via digital communication.

[0047] This simplifies wiring and reduces the number of wires compared to providing analog signal wiring to transmit duty cycle command values ​​for each switching element constituting the driver circuit. Furthermore, it allows for proper control of the motor 80's drive. Specifically, by providing a memory unit 162 capable of storing duty cycle command values ​​in the pre-driver IC 160, responsiveness equivalent to analog communication can be ensured.

[0048] The timing at which the duty cycle command value acquired from the microcontroller 120 is reflected in the drive signal is defined as the acquisition command reflection timing (indicated by the solid star in Figure 6). The pre-driver IC 160 has an estimation calculation unit 163 that performs estimation calculations for the duty cycle command value related to the update of the drive signal at a timing different from the acquisition command reflection timing (for example, the dashed star in Figure 6).

[0049] In this embodiment, in a series of communication processes between the microcontroller 120 and the pre-driver IC 160, after the transmission and reception of the duty cycle command value, information other than the duty cycle command value is transmitted and received. For example, the process from the sensor input to communication B in Figure 6 corresponds to a "series of communication processes". After the completion of the series of communication processes, the microcontroller 120 calculates the duty cycle command value to be reflected in the drive signal and transmits it to the pre-driver IC 160. The estimation calculation unit 163 calculates the duty cycle command value to be reflected in the drive signal after receiving the duty cycle command value, based on the duty cycle command value received in this communication and the duty cycle command value that has already been reflected in the drive signal and is stored in the memory unit 162.

[0050] This allows for appropriate interpolation between the timing of command acquisition and reflection. Furthermore, even if communication delays occur compared to analog communication, the same level of responsiveness as when transmitting duty cycle command values ​​via analog communication can be ensured.

[0051] The pre-driver ICs 160, 170, 260, and 270 update the drive signals at timings set by the microcontrollers 120 and 220. In this embodiment, the duty cycle is updated according to the synchronization signal transmitted from the microcontroller 120. This makes it possible to synchronize the duty cycles of multiple driver circuits 150, 155, 250, and 255.

[0052] The pre-driver IC 160 has an abnormality monitoring unit 168, which holds the updated drive signal in the event of a communication abnormality. Furthermore, if a power supply voltage abnormality, output abnormality, or internal circuit abnormality is detected, it stops outputting the drive signal. This allows the pre-driver IC 160 to take appropriate action within the abnormal state.

[0053] If the microcontroller 120 detects an abnormality in the pre-driver IC 160, it can stop the output of the drive signal from the pre-driver IC 160 by a command from the microcontroller 120. Specifically, the microcontroller 120 has an enable signal output unit 127 that outputs an enable signal commanding whether or not to allow the output of the drive signal from the pre-driver IC 160, and by disallowing the enable signal, it is possible to stop the output of the drive signal from the pre-driver IC 160. This makes it possible to appropriately stop the output of the drive signal when the pre-driver IC 160 is abnormal.

[0054] (Second Embodiment) The second embodiment is shown in Figure 8. In the following embodiment, the duty cycle update is the main difference, so this point will be explained in detail. In Figures 8 to 11, the upper row shows an example of transmitting the duty cycle command value via analog communication, and the lower row shows an example of transmitting the duty cycle command value via digital communication. The analog communication example is the same as in Figure 6, and the synchronization signal is omitted.

[0055] When transmitting duty cycle command values ​​via digital communication, at update timings N1, N3, and N5, duty cycle updates are performed using the acquired duty cycle obtained from the microcontroller 120, as in the above embodiment. Also, at update timings N2 and N4, duty cycle updates are performed using the interpolated duty cycle calculated by the pre-driver IC 160, as in the above embodiment.

[0056] In this embodiment, between update timings N2 and N3, the pre-driver IC 160 controls the duty cycle command value D （Ｎ１） , D （Ｎ３）The interpolated duty cycle is calculated using a weighted average, etc., and the duty cycle is updated at an arbitrary step size. The step size for duty cycle estimation and reflection timing can be arbitrarily set from the microcontroller 120, for example, by configuration settings. This makes it possible to increase the duty cycle update frequency. Similarly, between update timings N4 and N5, the pre-driver IC 160 adjusts the duty cycle command value D （Ｎ３） , D （Ｎ４） The interpolation duty cycle is calculated using a weighted average or the like, and the duty cycle is updated with an arbitrary step size. This configuration also produces the same effects as the embodiment described above.

[0057] (Third Embodiment) The third embodiment is shown in Figure 9. In this embodiment, similar to the second embodiment, the pre-driver IC 160 controls the duty cycle command value D between update timings N2 and N3. （Ｎ１） , D （Ｎ３） The interpolated duty cycle is calculated using a weighted average, etc., and the duty cycle is updated with an arbitrary step size. Also, between update timings N3 and N4, the pre-driver IC 160 adjusts the duty cycle command value D （Ｎ１） , D （Ｎ３） The interpolated duty cycle is calculated based on the prediction, and the duty cycle is updated with an arbitrary step size. For example, by changing the duty cycle by the same amount of change as the update timings N2 and N3, the interpolated duty cycle can be calculated based on the prediction. This makes it possible to increase the frequency of duty cycle updates. It also achieves the same effects as the embodiment described above.

[0058] (Fourth Embodiment) The fourth embodiment is shown in Figures 10 and 11. In Figure 10, the command values ​​in a series of communications are labeled "A1" and "A2" in the order of communication, and in Figure 11, the command values ​​in a series of communications are labeled "A1", "A2", and "A3" in the order of communication. In this embodiment, the microcontroller 120 transmits multiple duty cycle command values ​​to the pre-driver IC 160 in a series of communications. In this embodiment, the estimation calculation unit 163 may be omitted. In the example of Figure 10, the microcontroller 120 calculates the duty cycle command value D to be updated at update timings N2 and N3 in the command calculation from timing N1. （Ｎ２） , D （Ｎ３） The duty cycle command value D is calculated. （Ｎ２） , D（Ｎ３） The data is sent to the pre-driver IC 160 in that order.

[0059] In the pre-driver IC 160, the received duty cycle command value D （Ｎ２） , D （Ｎ３） The value is stored in the memory unit 162, and the duty cycle is updated at a predetermined duty cycle update timing. In the example in Figure 10, the duty cycle command value D is updated at the update timing N2 before the completion of the series of communications. （Ｎ２） The duty cycle is updated using [this method]. Furthermore, at the update timing N3 after the completion of a series of communications, the duty cycle command value D （Ｎ３） Update the duty cycle using this method.

[0060] Furthermore, in the command calculation at timing N3, the microcontroller 120 updates the duty command value D at update timings N4 and N5. （Ｎ４） , D （Ｎ５） The following calculations are performed and the results are sent to the pre-driver IC 160 in this order. At update timings N4 and N5, the duty cycle command value D （Ｎ４） , D （Ｎ５） Update the instructions.

[0061] The pre-driver IC 160 reflects the duty cycle command values ​​transmitted from the microcontroller 120 in a series of communication processes in a pre-set order into the drive signal. The association between the reception order and the update timing is based on the configuration settings from the microcontroller 120. In this embodiment, the pre-driver IC 160 reflects the duty cycle command values ​​in the order they are acquired, but the acquisition order and the update order may be different.

[0062] The number of duty cycle command values ​​sent in a series of communication processes is arbitrary and is set according to the duty cycle update interval and the time required for digital communication. Furthermore, if the number of duty cycle command values ​​transmitted in a series of communications is k, the memory unit 162 is configured to hold at least k duty cycle command values.

[0063] For example, as shown in Figure 11, in the command calculation at timing N1, three duty cycle command values ​​are calculated, and the duty cycle command value D （Ｎ２） , D （Ｎ３） , D （Ｎ４）The following information is sent to the pre-driver IC 160 in this order. The pre-driver IC 160 receives the duty cycle command value D （Ｎ２） , D （Ｎ３） , D （Ｎ４） The duty cycle is updated in the following order.

[0064] Furthermore, in the command calculation at timing N4, the microcontroller 120 calculates the duty cycle command value D （Ｎ５） , D （Ｎ６） , D （Ｎ７） The following calculations are performed and the results are sent to the pre-driver IC 160 in this order. The pre-driver IC receives the duty cycle command value D （Ｎ５） , D （Ｎ６） , D （Ｎ７） The duty cycle is updated in this order. In this way, by increasing the number of command values ​​sent in a single communication, the communication frequency can be reduced without degrading the responsiveness of the motor drive.

[0065] The microcontroller 120 transmits multiple duty cycle command values ​​corresponding to multiple update timings through a series of communication processes between the microcontroller 120 and the pre-driver IC 160. The pre-driver IC 160 stores the multiple duty cycle command values ​​acquired through the series of communication processes in the memory unit 162 and reflects them in the drive signal in the set order. This ensures that even when transmitting duty cycle command values ​​via digital communication, the same responsiveness as when transmitting via analog communication can be achieved. Furthermore, it provides the same effects as the embodiment described above.

[0066] In this embodiment, the ECU 15 corresponds to the "rotating electric machine control device," the motor 80 to the "rotating electric machine," the microcontrollers 120 and 220 to the "control unit," the pre-driver ICs 160, 170, 260, and 270 to the "driver drive unit," the memory unit 162 to the "storage unit," and the duty cycle output unit 166 to the "signal output unit." The duty cycle command value corresponds to the "drive command value," and the gate waveform output from the duty cycle output unit 166 corresponds to the "drive signal."

[0067] (Other Embodiments) In the above embodiment, the drive device has two power supply systems, and four pre-driver ICs and motor windings are provided for two microcontrollers. In other embodiments, the number of power supply systems may be one or three or more. Also, the number of microcontrollers, the number of pre-driver ICs and the number of motor windings may differ from those in the above embodiment.

[0068] In the above embodiment, the rotating electric machine is a motor. In other embodiments, the rotating electric machine may be a so-called motor-generator or generator that also functions as a generator. In the above embodiment, the rotating electric machine control device is applied to an electric power steering system. In other embodiments, the rotating electric machine control device may be applied to an in-vehicle device other than an electric power steering system (e.g., a steer-by-wire system), or to a device other than an in-vehicle device.

[0069] (Disclosure of Technical Ideas) This specification discloses several technical ideas as described in the following paragraphs. Some paragraphs may be written in a multiple dependent form, where subsequent paragraphs optionally refer to preceding paragraphs. Furthermore, some paragraphs may be written in a multiple dependent form, where they refer to other multiple dependent forms. These paragraphs written in multiple dependent forms define several technical ideas.

[0070] (Technical Concept 1) A rotating electric machine control device for controlling the drive of a rotating electric machine (80), comprising: a control unit (120, 220) that calculates a drive command value for the rotating electric machine; a signal output unit (166) that outputs a drive signal corresponding to the drive command value to a driver circuit (150, 155, 250, 255) that switches the energization of the rotating electric machine; and a driver drive unit (160, 170, 260, 270) that has a storage unit (162) capable of storing the drive command value acquired from the control unit and acquires the drive command value from the control unit by digital communication. (Technical Concept 2) The rotating electric machine control device according to Technical Concept 1, wherein the timing for reflecting the drive command value acquired from the control unit in the drive signal is defined as the acquisition command reflection timing, and the driver drive unit has an estimation calculation unit (163) that performs estimation calculation of the drive command value related to updating the drive signal at a timing different from the acquisition command reflection timing. (Technical Concept 3) The control unit calculates the drive command value to be reflected in the drive signal after the completion of a series of communication processes and transmits it to the driver drive unit, and the estimation calculation unit calculates the drive command value to be reflected in the drive signal after receiving the drive command value, based on the drive command value received in the current communication and the drive command value that has already been reflected in the drive signal and is stored in the storage unit, as described in Technical Concept 2. (Technical Concept 4) The control unit transmits a plurality of drive command values ​​corresponding to a plurality of update timings in a series of communication processes between the control unit and the driver drive unit, as described in Technical Concept 1. (Technical Concept 5) The driver drive unit stores a plurality of drive command values ​​acquired in a series of communication processes in the storage unit and reflects them in the drive signal in the set order, as described in Technical Concept 4. (Technical Concept 6) The driver drive unit updates the drive signal at a timing set by the control unit, as described in any one of Technical Concepts 1 to 5, as described in Technical Concept 6. (Technical Concept 7) The driver drive unit has an abnormality monitoring unit (168) and, in the event of a communication abnormality, retains the reflected drive signal. Rotating electric machine control device according to any one of Technical Concepts 1 to 6.(Technical Concept 8) The rotating electric machine control device according to any one of Technical Concepts 1 to 7, wherein the driver drive unit has an abnormality monitoring unit (168), and when an abnormality in the power supply voltage, output abnormality, or internal circuit abnormality is detected, the output of the drive signal is stopped. (Technical Concept 9) The rotating electric machine control device according to any one of Technical Concepts 1 to 8, wherein the control unit can stop the output of the drive signal from the driver drive unit by a command from the control unit when an abnormality in the driver drive unit is detected.

[0071] The control unit and its method described herein may be implemented by a dedicated computer provided by configuring a processor and memory programmed to perform one or more functions embodied by a computer program. Alternatively, the control unit and its method described herein may be implemented by a dedicated computer provided by configuring a processor by one or more dedicated hardware logic circuits. Alternatively, the control unit and its method described herein may be implemented by one or more dedicated computers configured by a combination of a processor and memory programmed to perform one or more functions and a processor configured by one or more hardware logic circuits. Furthermore, the computer program may be stored as instructions executed by the computer on a computer-readable non-transitional tangible recording medium. The foregoing, this disclosure is not limited in any way to the embodiments described above, and can be implemented in various forms without departing from the spirit thereof.

[0072] This disclosure is described in accordance with embodiments. However, this disclosure is not limited to such embodiments and structures. This disclosure also includes various modifications and variations within the scope of equivalents. Furthermore, various combinations and forms, as well as other combinations and forms that include only one, more, or fewer of those elements, fall within the scope and idea of ​​this disclosure.

Claims

1. A rotating electric machine control device for controlling the drive of a rotating electric machine (80), comprising: a control unit (120, 220) that calculates a drive command value for the rotating electric machine; a signal output unit (166) that outputs a drive signal corresponding to the drive command value to a driver circuit (150, 155, 250, 255) that switches the energization of the rotating electric machine; and a driver drive unit (160, 170, 260, 270) that has a storage unit (162) capable of storing the drive command value acquired from the control unit and acquires the drive command value from the control unit via digital communication.

2. The rotating electric machine control device according to claim 1, wherein the timing for reflecting the drive command value acquired from the control unit into the drive signal is defined as the acquisition command reflection timing, and the driver drive unit has an estimation calculation unit (163) that performs estimation calculation of the drive command value related to updating the drive signal at a timing different from the acquisition command reflection timing.

3. The control unit calculates the drive command value to be reflected in the drive signal after the completion of a series of communication processes and transmits it to the driver drive unit, and the estimation calculation unit calculates the drive command value to be reflected in the drive signal after receiving the drive command value, based on the drive command value received in the current communication and the drive command value that has already been reflected in the drive signal and is stored in the storage unit, the rotating electric machine control device according to claim 2.

4. The control unit transmits a plurality of drive command values ​​corresponding to a plurality of update timings in a series of communication processes between the control unit and the driver drive unit, as described in claim 1.

5. The rotary electric machine control device according to claim 4, wherein the driver drive unit stores a plurality of drive command values ​​obtained in a series of communication processes in the storage unit and reflects them in the drive signal in the set order.

6. The rotary electric machine control device according to any one of claims 1 to 5, wherein the driver drive unit updates the drive signal at a timing set by the control unit.

7. The rotating electric machine control device according to any one of claims 1 to 5, wherein the driver drive unit has an abnormality monitoring unit (168) and, in the event of a communication abnormality, holds the reflected drive signal.

8. The rotating electric machine control device according to any one of claims 1 to 5, wherein the driver drive unit has an abnormality monitoring unit (168), and when an abnormality in power supply voltage, output abnormality, or internal circuit abnormality is detected, the output of the drive signal is stopped.

9. The control unit can stop the output of the drive signal from the driver drive unit by a command from the control unit when it detects an abnormality in the driver drive unit, according to any one of claims 1 to 5.

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