Rotating electrical machine control device

Abstract

The present invention relates to a rotating electrical machine control device. The rotating electrical machine control device (10) controls the drive of a rotating electrical machine (80) having a motor winding (180, 280). A plurality of control units (150, 250) can communicate with each other and have: a drive control unit (151, 251), a mode selection unit (152, 252), an abnormality monitoring unit (155, 255) and a storage unit (156, 256). The mode selection unit (152, 252) sets the normal drive mode to a coordinated drive mode, and switches the drive mode from the coordinated drive mode to the independent drive mode when a communication abnormality or a synchronization abnormality, that is, an abnormality that cannot be coordinated, between the control units (150, 250) is detected. In addition, after the mode is switched to the independent drive mode due to an abnormality that cannot be coordinated, when it is determined based on other system monitoring information that other systems have stopped, the mode selection unit (152, 252) switches the drive mode from the independent drive mode to the standby mode.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application is based on patent application No. 2019-149072 filed on August 15, 2019, and its contents are cited herein. Technical Field

[0003] The present disclosure relates to a rotating electric machine control device. Background Art

[0004] Conventionally, there is known a rotary electric machine control device that controls the driving of a motor by a plurality of control units. For example, in Patent Document 1, two control units are provided, and a command value calculated by a master control unit is sent to a slave control unit to coordinate the two systems.

[0005] Patent Document 1: Japanese Patent Application Publication No. 2018-130007

[0006] However, sometimes in a redundant system, when a part of the system stops, the output of the normal system is increased to compensate for the output of the stopped system. Here, when the cause of the stop is a temporary reason such as a power outage or a microcomputer reset, if the stopped system is restored while the normal system is increasing the output, it may cause an unexpected action such as over-output. The purpose of the present disclosure is to provide a rotating electrical machine control device that appropriately controls the drive of a rotating electrical machine. Summary of the invention

[0007] The rotary electric machine control device disclosed in the present invention is a device for controlling the drive of a rotary electric machine having a motor winding, and is provided with a plurality of inverter units and a plurality of control units. The inverter unit switches the energization of the motor winding. The control units are capable of communicating with each other and have: a drive control unit that controls a correspondingly arranged inverter unit, a mode selection unit that selects a drive mode, an abnormality monitoring unit that performs abnormality monitoring, and a storage unit that stores abnormality information corresponding to the abnormality monitoring result. Here, the combination of the correspondingly arranged inverter unit and the control unit is referred to as a system.

[0008] The drive mode includes a coordinated drive mode, an independent drive mode, and a standby mode. The coordinated drive mode uses the values ​​obtained from other control units through communication and the values ​​calculated by the own control unit to control the energization of the motor windings in multiple systems. The independent drive mode does not use the values ​​obtained from other control units, but controls the energization of the motor windings in a manner that produces the same output as the amount that the system bears when driving all systems. In the standby mode, the output characteristics are changed to control the energization of the motor windings without using the values ​​obtained from other control units, so as to compensate the output of other systems in one system.

[0009] The mode selection unit sets the normal driving mode to the coordinated driving mode, and switches the driving mode from the coordinated driving mode to the independent driving mode when an abnormality that cannot be coordinated is detected, wherein the abnormality that cannot be coordinated is a communication abnormality or a synchronization abnormality between the control units. In addition, after the mode is switched to the independent driving mode due to the abnormality that cannot be coordinated, when it is determined based on other system monitoring information that other systems are stopped, the mode selection unit switches the driving mode from the independent driving mode to the standby mode. Thus, the driving of the rotating electrical machine can be appropriately controlled. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] The above-mentioned objects and other objects, features and advantages of the present disclosure will become more apparent through the following detailed description with reference to the accompanying drawings. In the accompanying drawings:

[0011] Figure 1 is a schematic structural diagram of a steering system according to a first embodiment,

[0012] Figure 2 is a sectional view of a driving device according to a first embodiment,

[0013] Figure 3 yes Figure 2 The III-III line cross-sectional view,

[0014] Figure 4 is a block diagram showing an ECU according to a first embodiment,

[0015] Figure 5 is a circuit diagram illustrating a power supply relay according to a first embodiment.

[0016] Figure 6 is an explanatory diagram for explaining the relationship between the steering torque and the assist torque when the two systems are driven according to the first embodiment.

[0017] Figure 7 is an explanatory diagram for explaining the relationship between the steering torque and the assist torque in the single system drive mode according to the first embodiment.

[0018] Figure 8 is a flowchart for explaining the drive mode selection process according to the first embodiment.

[0019] Fig. 9 is a flowchart for explaining the diagnosis storage process according to the first embodiment.

[0020] Fig.10 is a timing chart for explaining the communication abnormality processing according to the first embodiment.

[0021] Fig.11is a timing chart for explaining the communication abnormality processing according to the first embodiment.

[0022] Fig.12 is a timing chart for explaining the communication abnormality processing according to the first embodiment.

[0023] Fig.13 is a timing chart for explaining the communication abnormality processing according to the first embodiment.

[0024] Fig.14 is a flowchart for explaining the drive mode selection process according to the second embodiment.

[0025] Fig.15 is a sequence diagram for explaining the communication abnormality processing according to the second embodiment.

[0026] Fig.16 is a sequence diagram for explaining the communication abnormality processing according to the second embodiment.

[0027] Fig.17 is an explanatory diagram for explaining the relationship between the steering torque and the assist torque according to a reference example.

[0028] Fig.18 This is a sequence diagram for explaining the communication abnormality processing according to the reference example. DETAILED DESCRIPTION

[0029] Hereinafter, a rotating electrical machine control device according to the present disclosure will be described based on the drawings. In the following, in a plurality of embodiments, substantially the same configurations are denoted by the same reference numerals and description thereof will be omitted.

[0030] (First Embodiment)

[0031] Figures 1 to 13 It represents the first embodiment. Figure 1 As shown, the ECU 10 as a rotary electric machine control device controls the driving of a motor 80 as a rotary electric machine, and is applied together with the motor 80 to an electric power steering device 8 as a steering device for assisting a steering operation of a vehicle, for example. Figure 1 The structure of a steering system 90 including the electric power steering device 8 is shown. The steering system 90 includes a steering wheel 91 as a steering member, a steering shaft 92, a pinion 96, a rack shaft 97, wheels 98, the electric power steering device 8, and the like.

[0032] The steering wheel 91 is connected to the steering shaft 92. A torque sensor 94 for detecting the steering torque is provided on the steering shaft 92. The torque sensor 94 includes a first sensor unit 194 and a second sensor unit 294, and the sensors capable of detecting their own failures are duplicated. A pinion 96 is provided at the front end of the steering shaft 92. The pinion 96 meshes with a rack shaft 97. A pair of wheels 98 are connected to both ends of the rack shaft 97 via a tie rod or the like.

[0033] 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 the linear motion of the rack shaft 97 through the pinion 96. The pair of wheels 98 are steered to an angle corresponding to the displacement of the rack shaft 97.

[0034] The electric power steering device 8 includes a motor 80, a reduction gear 89 as a power transmission unit that reduces the rotation of the motor 80 and transmits it to the steering shaft 92, and an ECU 10. That is, the electric power steering device 8 of this embodiment is a so-called "column-assisted type", and the steering shaft 92 can be said to be a driven object. It can also be a so-called "rack-assisted type" that transmits the rotation of the motor 80 to the rack shaft 97.

[0035] like Figure 1 to Figure 4 As shown, the motor 80 outputs part or all of the torque required for steering operation and is driven by power supplied from the battery 101 or 201 as a power source to rotate the reduction gear 89 forward and reversely. The motor 80 is a three-phase brushless motor having a rotor 860 and a stator 840.

[0036] The motor 80 has a first motor winding 180 and a second motor winding 280. The motor windings 180 and 280 have the same electrical characteristics and are wound around a common stator 840 with an electrical angle of 30 degrees offset from each other. Thus, the motor windings 180 and 280 are controlled to have a current-carrying phase of The phase currents are staggered by 30[deg]. The output torque is improved by optimizing the phase difference of the power supply. In addition, the sixth-order torque ripple can be reduced, and the noise and vibration can be reduced. In addition, the current is also dispersed, so that the heat is dispersed and balanced, so that the temperature-dependent system errors such as the detection values ​​of each sensor and the torque can be reduced, and the amount of current that can be energized can be increased. In addition, the motor windings 180 and 280 can be wound without offsetting each other, and the electrical characteristics can be different.

[0037] Hereinafter, a combination of the first inverter unit 120 and the first control unit 150 involved in the power-on control of the first motor winding 180 is set as the first system L1, and a combination of the second inverter unit 220 and the second control unit 250 involved in the power-on control of the second motor winding 280 is set as the second system L2. In addition, the structures involved in the first system L1 are mainly numbered with the 100 series, and the structures involved in the second system L2 are mainly numbered with the 200 series. In addition, in the first system L1 and the second system L2, the same or similar structures are numbered in the same manner with the last two digits. In the following, "first" is appropriately recorded as the subscript "1", and "second" is appropriately recorded as the subscript "2".

[0038] like Figure 2 As shown, in the drive device 40, the ECU 10 is integrally provided on one side of the axial direction of the motor 80, which is a so-called "mechatronic type", but the motor 80 and the ECU 10 may be provided separately. On the side opposite to the output shaft of the motor 80, the ECU 10 is coaxially arranged with the axis Ax of the shaft 870. The ECU 10 may also be provided on the output shaft side of the motor 80. By setting it as a mechatronic type, the ECU 10 and the motor 80 can be efficiently arranged in a vehicle with limited mounting space.

[0039] The motor 80 includes a stator 840, a rotor 860, and a housing 830 accommodating them. The stator 840 is fixed to the housing 830 and is wound around the motor windings 180 and 280. The rotor 860 is provided radially inside the stator 840 and is provided to be relatively rotatable with respect to the stator 840.

[0040] The shaft 870 is embedded in the rotor 860 and rotates integrally with the rotor 860. The shaft 870 is rotatably supported by the housing 830 via bearings 835 and 836. The end of the shaft 870 on the ECU 10 side protrudes from the housing 830 toward the ECU 10 side. A magnet 875 is provided at the end of the shaft 870 on the ECU 10 side.

[0041] The housing 830 includes a bottomed cylindrical housing 834 including a rear frame end 837 and a front frame end 838 provided on the opening side of the housing 834. The housing 834 and the front frame end 838 are fastened to each other by bolts or the like. A wire insertion hole 839 is formed in the rear frame end 837. The wires 185 and 285 connected to the respective phases of the motor windings 180 and 280 are inserted through the wire insertion hole 839. The wires 185 and 285 are led out from the wire insertion hole 839 to the ECU 10 side and connected to the substrate 470.

[0042] ECU10 includes: a cover 460, a radiator 465 fixed to the cover 460, a substrate 470 fixed to the radiator 465, and various electronic components mounted on the substrate 470. The cover 460 protects the electronic components from external impacts or prevents dust, water, etc. from penetrating into the interior of the ECU10. The cover body 461 of the cover 460 and the connector parts 103 and 203 are formed integrally. The connector parts 103 and 203 can also be separated from the cover body 461. The terminals 463 of the connector parts 103 and 203 are connected to the substrate 470 via wiring, etc., which is not shown in the figure. The number of connectors and the number of terminals can be appropriately changed according to the number of signals, etc. The connector parts 103 and 203 are arranged at the axial end of the drive device 40 and open on the opposite side of the motor 80.

[0043] The substrate 470 is, for example, a printed circuit board, and is disposed opposite to the rear frame end 837. Electronic components for two systems are independently mounted on the substrate 470 for each system, forming a fully redundant structure. In this embodiment, electronic components are mounted on one substrate 470, but electronic components may be mounted on a plurality of substrates.

[0044] Of the two main surfaces of the substrate 470, the surface on the motor 80 side is set as a motor surface 471, and the surface on the opposite side to the motor 80 is set as a cover surface 472. Figure 3 As shown, the switching element 121 constituting the inverter unit 120, the switching element 221 constituting the inverter unit 220, the angle sensors 126, 226, the custom ICs 135, 235, etc. are mounted on the motor surface 471. The angle sensors 126, 226 are mounted at a location opposite to the magnet 875 so as to be able to detect changes in the magnetic field accompanying the rotation of the magnet 875.

[0045] Capacitors 128, 228, inductors 129, 229, and microcomputers constituting control units 150, 250 are mounted on cover surface 472. Figure 3 In the figure, the microcomputers constituting the control units 150 and 250 are numbered "150" and "250", respectively. The capacitors 128 and 228 smooth the power input from the batteries 101 and 201. In addition, the capacitors 128 and 228 assist in the power supply to the motor 80 by accumulating charge. The capacitors 128 and 228 and the inductors 129 and 229 constitute a filter circuit to reduce noise transmitted from other devices that share the battery, and reduce noise transmitted from the drive device 40 to other devices that share the battery. In addition, although Figure 3 Although not shown in the figure, the power supply relays 122 , 222 , the motor relays 125 , 225 , the current sensors 127 , 227 , etc. are also mounted on the motor surface 471 or the cover surface 472 .

[0046] like Figure 4As shown, the ECU 10 includes inverter units 120, 220 and control units 150, 250, etc. The ECU 10 is provided with connector units 103, 203. The first connector unit 103 is provided with a first power terminal 105, a first ground terminal 106, a first IG terminal 107, a first communication terminal 108, and a first torque terminal 109.

[0047] The first power terminal 105 is connected to the first battery 101 via a fuse not shown. The power supplied from the positive electrode of the first battery 101 via the first power terminal 105 is supplied to the first motor winding 180 via the power relay 122, the inverter unit 120, and the motor relay 125. The first ground terminal 106 is connected to the first ground GND1, which is the ground of the first system inside the ECU 10, and the first external ground GB1, which is the ground of the first system outside the ECU 10. In the system of the vehicle, the metal body becomes a common GND plane, and the first external ground GB1 represents one of the connection points on the GND plane, and the negative electrode of the second battery 201 is also connected to the connection point on the GND plane.

[0048] The first IG terminal 107 is connected to the positive electrode of the first battery 101 via a first switch that is turned on / off in conjunction with a start switch of the vehicle such as an ignition switch. The power supplied from the first battery 101 via the first IG terminal 107 is supplied to the first custom IC 135. The first custom IC 135 includes a first drive circuit 136, a first circuit power supply 137, a microcomputer monitor not shown, and a current monitoring amplifier not shown.

[0049] The first communication terminal 108 is connected to the first vehicle communication circuit 111 and the first vehicle communication network 195. The first vehicle communication network 195 and the first control unit 150 are connected in a manner capable of sending and receiving via the first vehicle communication circuit 111. In addition, the first vehicle communication network 195 and the second control unit 250 are configured to be connected in a manner capable of receiving information, and even if the second control unit 250 fails, it will not affect the first vehicle communication network 195 including the first control unit 150.

[0050] The first torque terminal 109 is connected to the first sensor unit 194 of the torque sensor 94. The detection value of the first sensor unit 194 is input to the first control unit 150 via the first torque terminal 109 and the first torque sensor input circuit 112. Here, the first sensor unit 194 and the first control unit 150 are configured to detect a failure of the torque sensor input circuit system.

[0051] The second connector 203 is provided with a second power terminal 205, a second ground terminal 206, a second IG terminal 207, a second communication terminal 208, and a second torque terminal 209. The second power terminal 205 is connected to the positive electrode of the second battery 201 via a fuse not shown. The power supplied from the second battery 201 via the second power terminal 205 is supplied to the second motor winding 280 via the power relay 222, the inverter unit 220, and the motor relay 225. The second ground terminal 206 is connected to the second ground GND2, which is the ground of the second system inside the ECU 10, and the second external ground GB2, which is the ground of the second system outside the ECU 10. In the system of the vehicle, the metal body becomes a common GND plane, the second external ground GB2 represents one of the connection points on the GND plane, and the negative electrode of the second battery 201 is also connected to the connection point on the GND plane. Here, at least different systems are configured not to be connected to the same connection point on the GND plane.

[0052] The second IG terminal 207 is connected to the positive electrode of the second battery 201 via a second switch that is turned on / off controlled in conjunction with the vehicle's start switch. The power supplied from the second battery 201 via the second IG terminal 207 is supplied to the second custom IC 235. The second custom IC 235 includes a second drive circuit 236, a second circuit power supply 237, a microcomputer monitor (not shown), and a current monitoring amplifier (not shown).

[0053] The second communication terminal 208 is connected to the second vehicle communication circuit 211 and the second vehicle communication network 295. The second vehicle communication network 295 and the second control unit 250 are connected in a manner capable of sending and receiving via the second vehicle communication circuit 211. In addition, the second vehicle communication network 295 and the first control unit 150 are configured to be connected in a manner capable of receiving information, and even if the first control unit 150 fails, it will not affect the second vehicle communication network 295 including the second control unit 250.

[0054] The second torque terminal 209 is connected to the second sensor unit 294 of the torque sensor 94. The detection value of the second sensor unit 294 is input to the second control unit 250 via the second torque terminal 209 and the second torque sensor input circuit 212. Here, the second sensor unit 294 and the second control unit 250 are configured to detect a failure of the torque sensor input circuit system.

[0055] exist Figure 4 In the embodiment, the communication terminals 108 and 208 are connected to different vehicle communication networks 195 and 295, respectively, but they may be connected to the same vehicle communication network. Figure 4In the figure, CAN (Controller Area Network) is exemplified as the vehicle communication networks 195 and 295, but a network of a standard other than CAN, such as CAN-FD (CAN with Flexible Data rate) and FlexRay, may also be used.

[0056] The first inverter unit 120 is a three-phase inverter having a switching element 121 , and converts the power of the first motor winding 180 . The second inverter unit 220 is a three-phase inverter having a switching element 221 , and converts the power of the second motor winding 280 .

[0057] The first power supply relay 122 is provided between the first power supply terminal 105 and the first inverter unit 120. The first motor relay 125 is provided at each phase between the first inverter unit 120 and the first motor winding 180. The second power supply relay 222 is provided at each phase between the second power supply terminal 205 and the second inverter unit 220. The second motor relay 225 is provided between the second inverter unit 220 and the second motor winding 280.

[0058] In the present embodiment, the switch elements 121, 221, the power relays 122, 222, and the motor relays 125, 225 are all MOSFETs, but other elements such as IGBTs may also be used. Figure 5 As shown, when the first power supply relay 122 is composed of an element having a parasitic diode such as a MOSFET, it is preferable to connect the two elements 123 and 124 in series so that the directions of the parasitic diodes are opposite. The second power supply relay 222 is the same, so it is omitted in the figure. Thus, when the batteries 101 and 201 are mistakenly connected in reverse, the reverse current can be prevented from flowing. The power supply relays 122 and 222 can also be mechanical relays.

[0059] like Figure 4 As shown, the first switching element 121 , the first power supply relay 122 and the first motor relay 125 are turned on / off by the first control unit 150 . The second switching element 221 , the second power supply relay 222 and the second motor relay 225 are turned on / off by the second control unit 250 .

[0060] The first angle sensor 126 detects the rotation angle of the motor 80 and outputs the detection value to the first control unit 150. The second angle sensor 226 detects the rotation angle of the motor 80 and outputs the detection value to the second control unit 250. Here, the first angle sensor 126 and the first control unit 150, and the second angle sensor 226 and the second control unit 250 are configured to detect a failure of each angle sensor input circuit system.

[0061] The first current sensor 127 detects the current flowing through each phase of the first motor winding 180. The detection value of the first current sensor 127 is amplified by the amplifier circuit in the custom IC 135 and output to the first control unit 150. The second current sensor 227 detects the current flowing through each phase of the second motor winding 280. The detection value of the second current sensor 227 is amplified by the amplifier circuit in the custom IC 235 and output to the second control unit 250.

[0062] The first drive circuit 136 outputs drive signals for driving the first switching element 121, the first power supply relay 122, and the first motor relay 125 to the respective elements based on the control signal from the first control unit 150. The second drive circuit 236 outputs drive signals for driving the second switching element 221, the second power supply relay 222, and the second motor relay 225 to the respective elements based on the control signal from the second control unit 250.

[0063] The circuit power supply 137 is connected to the power supply terminal 105 and the IG terminal 107, and supplies power to the first control unit 150. The circuit power supply 237 is connected to the power supply terminal 205 and the IG terminal 207, and supplies power to the second control unit 250.

[0064] The control units 150 and 250 are mainly composed of microcomputers, etc., and are internally equipped with CPU, ROM, RAM, I / O, and buses connecting these structures, etc., which are not shown in the figure. Each process in the control units 150 and 250 can be a software process performed by the CPU executing a program pre-stored in a physical memory device such as ROM (i.e., a readable non-temporary tangible storage medium), or a hardware process based on a dedicated electronic circuit. Here, the first control unit 150 and the second control unit 250 are configured to detect their own faults, for example, using a lock-step dual microcomputer.

[0065] The first control unit 150 includes a drive control unit 151, a mode selection unit 152, an abnormality monitoring unit 155, a storage unit 156, and a synchronization processing unit 157. The drive control unit 151 controls the energization of the first motor winding 180 by controlling the on / off operation of the first switching element 121. In addition, the drive control unit 151 controls the on / off operation of the first power supply relay 122 and the first motor relay 125.

[0066] The second control unit 250 includes a drive control unit 251, a mode selection unit 152, an abnormality monitoring unit 255, a storage unit 256, and a synchronization processing unit 257. The drive control unit 251 controls the energization of the second motor winding 280 by controlling the on / off operation of the second switching element 221. In addition, the drive control unit 251 controls the on / off operation of the second power supply relay 222 and the second motor relay 225. The drive control units 151 and 251 control the drive of the motor 80, for example, by current feedback control, but the details of the control method of the motor control may be other than current feedback control.

[0067] The mode selection units 152 and 252 select the drive mode involved in the drive control of the motor 80. The drive mode in the present embodiment includes a coordinated drive mode, an independent drive mode, and a single system drive mode. Normally, the drive of the motor 80 is controlled by the coordinated drive mode. Here, the so-called normal time refers to the situation where the systems L1 and L2 are normal and the coordinated drive of the two systems can be performed. In the following, the control in the coordinated drive mode at normal times is appropriately set as "normal control". In the present embodiment, the situation where the communication between microcomputers is abnormal or the synchronization between systems cannot be achieved is set as an abnormality that cannot be coordinated. For the judgment of the abnormality that cannot be coordinated, the communication between microcomputers or the synchronization between systems can also be omitted. In the following, it is assumed that the synchronization between systems is normal, and the processing corresponding to the communication status between microcomputers is explained.

[0068] In the coordinated drive mode, when both the control units 150 and 250 are normal and the communication between the microcomputers is normal, at least one value is shared between the systems so that the systems coordinate to control the drive of the motor 80. In the present embodiment, the current command value, the current detection value, and the current limit value are shared as control information. In the present embodiment, the first control unit 150 is set as the master control unit, and the second control unit 250 is set as the slave control unit. The current command value calculated by the first control unit 150 as the host is sent to the second control unit 250, and the same current command value calculated by the first control unit 150 is used in the control units 150 and 250. The shared current command value can be a value after current limitation or a value before current limitation. In the present embodiment, in the coordinated drive mode, current control is performed by controlling the current sum and the current difference of the two systems, which is called "sum and difference control".

[0069] In the independent drive mode, control information of other systems is not used, and each system independently controls the drive of the motor 80. In the single-system drive mode, one system is stopped, and control information of other systems is not used, and the drive of the motor 80 is controlled in one system. Here, even if there are three or more systems, the drive mode for driving the motor 80 in one system is set to the "single-system drive mode".

[0070] based on Figure 6 and Figure 7 The output characteristics in each driving mode are described. In the present embodiment, the output torque output from the motor 80, that is, the assist torque Ta is set according to the steering torque Ts. Figure 6 In FIG. 1 , the horizontal axis is the steering torque Ts, and the vertical axis is the assist torque Ta. In the cooperative drive mode and the independent drive mode, the total output of the two systems is indicated by a solid line, and the output of the first system L1 is indicated by a dotted line.

[0071] like Figure 6 As shown, in the range from the steering torque Ts to the upper limit reaching value Ts2, the auxiliary torque Ta increases as the steering torque Ts increases, and in the range from the steering torque Ts to the upper limit reaching value Ts2 or above, the auxiliary torque Ta becomes the output upper limit value Ta_max2. If the performance, etc. are the same in the first system L1 and the second system L2, the first system L1 and the second system L2 each bear 1 / 2 of the output of the motor 80. That is, the output upper limit value Ta_max1 in one system is 1 / 2 of the output upper limit value Ta_max2 in both systems. In addition, the increase ratio of the auxiliary torque Ta in one system to the steering torque Ts is 1 / 2 of that when the two systems are driven. Here, when one system is driven in the independent drive mode, as shown by the dotted line, the auxiliary torque Ta is 1 / 2 of that when the two systems are driven. In addition, in Figure 6 In the range up to the output upper limit value Ta_max2, the assist torque Ta increases linearly with the increase of the steering torque Ts, but may increase nonlinearly.

[0072] Figure 7 Indicates the output characteristics in single system drive mode. Figure 7In FIG. 1 , the output of the second system L2 when the single system is driven is indicated by a solid line, and the output of the two systems in normal state is indicated by a dotted line. In the single system driving mode, in the range from the steering torque Ts to the upper limit reaching value Ts1, the increase ratio of the assist torque Ta to the steering torque Ts is set to 2 times, so that the assist torque Ta relative to the steering torque Ts is the same as that in the two system driving mode. In addition, in the range from the steering torque Ts to the upper limit reaching value Ts1, the assist torque Ta is the output upper limit value Ta_max1 in the single system driving mode regardless of the steering torque Ts, and the assist torque Ta is smaller than that in the two system driving mode. In addition, if there is a margin for the rated current, etc., the output upper limit value Ta_max1 in the single system driving mode may be increased within the range below the output upper limit value Ta_max2 in the two system driving mode. In the following, the single system driving performed when the other system is abnormal is appropriately referred to as "standby control", and is also described as "BU control" in the figure. In addition, in the standby control, the output characteristic is changed, and at least one of the increase ratio of the assist torque Ta to the steering torque Ts and the output upper limit is increased as "increase output".

[0073] like Figure 4 As shown, the abnormality monitoring unit 155 monitors the abnormality of the first system L1 as the own system. In addition, when an abnormality that should stop the own system occurs, the first control unit 150 turns off at least one of the first inverter unit 120, the first power supply relay 122, and the first motor relay 125.

[0074] In addition, the abnormality monitoring unit 155 monitors the communication state with the second control unit 250 and the operation state of the second system L2. As a method for monitoring the operation state of the second system L2, the circuit (for example, the second inverter unit 220, the second power supply relay 222, and the second motor relay 225) of the system that stops when an abnormality of the second system L2 is detected or the state of at least one of the communication lines involved in the inter-microcomputer communication is monitored to determine whether an emergency stop is performed. In this embodiment, an other system relay monitoring circuit 139 is provided to obtain the second relay gate signal Vrg2 output from the second drive circuit 236 to the second power supply relay 222, so as to monitor the state of the second power supply relay 222 based on the second relay gate signal Vrg2.

[0075] The abnormality monitoring unit 255 monitors the abnormality of the second system L2 as the own system. When an abnormality that should stop the own system occurs, the second control unit 250 turns off at least one of the second inverter unit 220, the second power supply relay 222, and the second motor relay 225.

[0076] The abnormality monitoring unit 255 monitors the communication state with the first control unit 150 and the operation state of the first system L1. As a method for monitoring the operation state of the first system L1, the circuit (for example, the first inverter unit 120, the first power supply relay 122, and the first motor relay 125) of the system that stops when an abnormality of the first system L1 is detected or the state of at least one of the communication lines involved in the inter-microcomputer communication is monitored to determine whether an emergency stop is performed. In this embodiment, an other system relay monitoring circuit 239 is provided to obtain the first relay gate signal Vrg1 output from the first drive circuit 136 to the first power supply relay 122, so as to monitor the state of the first power supply relay 122 based on the first relay gate signal Vrg1.

[0077] In monitoring the first system L1 in the second control unit 250, instead of the relay gate signal Vrg1, the intermediate voltage of the two elements 123 and 124 constituting the power relay 122, the relay drive signal output from the control unit 150, or the relay post voltage between the power relay 122 and the inverter unit 120 may be used as other system relay information. The same is true for monitoring the second system L2 in the first control unit 150.

[0078] Hereinafter, the information obtained from the other system relay monitoring circuit is referred to as "other system relay information", the operation state of monitoring other systems based on the other system relay information is referred to as "other system relay monitoring", and the monitored relay is referred to as "other system relay". In addition, the state of the other system relay being turned on is referred to as "other system relay Hi", and the state of being turned off is referred to as "other system relay Lo".

[0079] When an abnormality occurs in the inter-microcomputer communication and the relay information of the other system is abnormal, the abnormality monitoring unit 155, 255 determines that the other system is abnormal. In addition, when an abnormality occurs in the inter-microcomputer communication and the relay information of the other system is normal, the abnormality monitoring unit 155, 255 determines that the control unit of the other system is normal and the abnormality occurs in the inter-microcomputer communication. That is, in this embodiment, by monitoring the inter-microcomputer communication state and the relay of the other system, it is distinguished whether the state of being unable to communicate is caused by the abnormality of the control unit of the other system or the abnormality of the inter-microcomputer communication.

[0080] The storage unit 156 is a nonvolatile memory that stores abnormal information related to the abnormality detected by the abnormality monitoring unit 155. The storage unit 256 is a nonvolatile memory that stores abnormal information related to the abnormality detected by the abnormality monitoring unit 255. The abnormal information stored in the storage units 156 and 256 includes information related to abnormal communication between microcomputers and information related to the stop of other systems. The abnormal information stored in the storage units 156 and 256 is used for abnormality analysis. In the following, the abnormal information is appropriately referred to as "diagnosis".

[0081] The synchronization processing units 157 and 257 perform synchronization processing to synchronize the control timings of the control units 150 and 250. The first control unit 150 has a clock generation circuit (not shown) to generate a drive timing based on the generated clock signal. The synchronization processing unit 157 generates a synchronization signal for synchronizing the drive timing with other systems and sends it to the second control unit 250.

[0082] The second control unit 250 has a clock generation circuit (not shown) to generate a drive timing based on the generated clock signal. The synchronization processing unit 257 performs correction based on the synchronization signal sent from the first control unit 150 so that the drive timing is consistent with the first system L1. The synchronization signal can be generated outside the control unit 150, 250, and the details of the synchronization processing can also be different. In addition, the communication line used for sending and receiving the synchronization signal can use a dedicated communication line, or it can share the signal line used for sending and receiving other information.

[0083] However, the state in which the control units 150 and 250 cannot communicate with each other may be caused by an abnormality of the power supply device outside the ECU 10, such as an abnormality of the battery 101 and 201, a disconnection of the wiring harness, etc., in addition to an internal fault of the ECU 10. In the present embodiment, since the information of other systems obtained through the inter-microcomputer communication is used for coordinated driving, it is preferred to quickly switch the driving mode when the inter-microcomputer communication is abnormal. On the other hand, if the abnormal information is diagnosed and stored while switching the driving mode, even a temporary abnormality such as a power outage will leave an abnormal history.

[0084] In addition, if the output characteristics are changed during standby control, there is a possibility of over-output when the system recovers after a temporary abnormality. Fig.17 As shown in FIG. 1 , as a reference example, when the second system L2 is already driven by the single system, if the output generated by the independent driving of the first system L1 is added, the output becomes excessive compared to the normal state within the range from the steering torque Ts to the upper limit reaching the value Ts2. Fig.17In the figure, the dotted line represents the output of the two systems in the coordinated driving mode, the double-dash line represents the output of the second system L2 in the single-system driving mode, the dot-dash line represents the output of the first system L1 in the independent driving mode, and the solid line represents the output of the two systems obtained by adding the output of the first system L1 in the single-system driving mode to the output of the second system L2.

[0085] Therefore, in the present embodiment, when an abnormality occurs in inter-microcomputer communication, the drive mode is changed in the abnormal determination of the first stage, and the diagnostic storage is performed in the abnormal determination of the second stage, so that the abnormal determination time of the first stage and the abnormal determination time of the second stage are different. In detail, the abnormal determination time of the second stage (for example, 3 [s]) is made longer than the abnormal determination time of the first stage (for example, several [ms]). It is preferred that the abnormal determination time of the first stage is as short as possible, and the abnormal determination time of the second stage is set according to the time required for the microcomputer reset and restart of other systems. In detail, it is set to a time that is longer than the time required for restarting as the amount of time allowed for a momentary power outage. In addition, in the case where other systems have been moved to standby control, over-output is prevented by setting this system to auxiliary stop. In addition, in the present embodiment, the time until the determination of the stop of other systems is equal to the abnormal determination time of the second stage.

[0086] based on Figure 8 The driving mode selection process of this embodiment is described in the flowchart. This process is executed in a predetermined cycle in the control unit 150, 250. Hereinafter, the "step" of step S101 is omitted and is simply represented by the symbol "S". The other steps are the same.

[0087] In S101, the control unit 150, 250 determines whether the inter-microcomputer communication is abnormal. If it is determined that the inter-microcomputer communication is abnormal (S101: Yes), the process moves to S107. If it is determined that the inter-microcomputer communication is normal (S101: No), the process moves to S102. In addition, if the inter-microcomputer communication is determined to be normal and the counters Ct1, Ct2, and Ct3 described later have been counted, they are reset.

[0088] In S102, the control unit 150, 250 determines whether cooperative driving is in progress. If it is determined that cooperative driving is in progress (S102: Yes), the process proceeds to S103 to continue cooperative driving. If it is determined that cooperative driving is not in progress (S102: No), the process proceeds to S104.

[0089] In S104, the control unit 150, 250 determines whether the other system has shifted to the backup control. If it is determined that the other system has shifted to the backup control (S104: Yes), the process moves to S105, and the drive mode is set to the auxiliary stop. If it is determined that the other system has not shifted to the backup control (S104: No), the process moves to S106, and the drive mode of the own system is set to the independent drive mode.

[0090] When it is determined that the inter-microcomputer communication is abnormal (S101: Yes), the control unit 150, 250 moves to S107 to determine whether the first-stage communication abnormality has been confirmed. When it is determined that the first-stage communication abnormality has been confirmed (S107: Yes), the process moves to S111. When it is determined that the first-stage communication abnormality has not been confirmed (S107: No), the process moves to S108 to increment the first-stage communication abnormality counter Ct1.

[0091] In S109, the control unit 150, 250 determines whether the first-stage communication abnormality counter Ct1 is greater than the first-stage determination judgment value TH1. The first-stage determination judgment value TH1 is set according to the abnormal determination time of the first stage. When it is determined that the first-stage communication abnormality counter Ct1 is less than the first-stage determination judgment value TH1 (S109: No), the processing of S110 is not performed and this routine ends. When it is determined that the first-stage communication abnormality counter Ct1 is greater than the first-stage determination judgment value TH1 (S109: Yes), it moves to S110, determines that the first-stage communication is abnormal, and sets the drive mode to independent drive. In addition, for example, the first-stage determination judgment value TH1 can be set to 0, and the independent drive mode can be immediately moved after the communication abnormality between microcomputers is detected.

[0092] When it is determined that the communication abnormality of the first stage has been confirmed (S107: Yes), the control unit 150, 250 moves to S111 to determine whether the other system relay is Lo. When it is determined that the other system relay is Hi (S111: No), the processing after S113 is not performed, and this routine ends. In addition, when the other system monitoring counter Ct3 is already counted, it is reset. When it is determined that the other system relay is Lo (S111: Yes), the routine moves to S112 to increase the other system monitoring counter Ct3.

[0093] In S113, the control unit 150, 250 determines whether the other system monitoring counter Ct3 is greater than the other system abnormality determination judgment value TH3. The other system abnormality determination judgment value TH3 is set according to the time to move from independent drive to standby control. When it is determined that the other system monitoring counter Ct3 is less than the other system abnormality determination judgment value TH3 (S113: No), the processing of S114 is not performed and this routine is terminated. When it is determined that the other system monitoring counter Ct3 is greater than the other system abnormality determination judgment value TH3 (S113: Yes), it moves to S114 to move to standby control. In addition, the other system stop is stored as a diagnosis in the storage unit 156, 256.

[0094] based on Fig. 9 The flowchart of will explain the diagnostic storage processing of the present embodiment. The processing is executed in the control unit 150, 250 at a predetermined cycle. In S151, the control unit 150, 250 determines whether the communication between the microcomputers is abnormal. When it is determined that the communication between the microcomputers is normal (S151: No), the processing after S152 is not performed. In addition, when the second-stage communication abnormality counter Ct2 described later has counted, it is reset. When it is determined that the communication between the microcomputers is abnormal (S151: Yes), move to S152.

[0095] In S152, the control unit 150, 250 determines whether the communication anomaly of the first stage has been confirmed. If it is determined that the communication anomaly of the first stage has not been confirmed (S152: No), the processing after S152 is not performed, and this routine ends. If it is determined that the communication anomaly of the first stage has been confirmed (S152: Yes), it moves to S153.

[0096] In S153, the control unit 150, 250 determines whether the system is in standby control. If it is determined that the system is in standby control (S153: Yes), the processing after S154 is not performed and the routine ends. If it is determined that the system is not in standby control (S153: No), the routine moves to S154.

[0097] In S154, the control unit 150, 250 determines whether the power is locked. After the start switch is turned off, the control unit 150, 250 continues to be turned on to perform the end process, etc., and is turned off after the end process is completed. In this embodiment, the state in which the control unit 150, 250 is turned on after the start switch is turned off is set as "power is locked". When it is determined that the power is locked (S154: Yes), the processing after S155 is not performed and this routine ends. When it is determined that the power is not locked (S154: No), it moves to S155.

[0098] In S155, the control unit 150, 250 determines whether the other system relay is Lo. If it is determined that the other system relay is Lo (S155: Yes), the processing after S156 is not performed and this routine ends. If it is determined that the other system relay is Hi (S155: No), it moves to S156.

[0099] In S156, the control unit 150, 250 increases the second-stage communication abnormality counter Ct2. In S157, it is determined whether the second-stage communication abnormality counter Ct2 is greater than the second-stage determination threshold TH2. In the present embodiment, the second-stage determination value TH2 is set according to the abnormal determination time of the second stage, and is set to the same value as the other system abnormality determination value TH3. In the case where it is determined that the second-stage communication abnormality counter Ct2 is less than the second-stage determination value TH2 (S157: No), the processing of S158 is not performed, and this routine ends. In the case where it is determined that the second-stage communication abnormality counter Ct2 is greater than the second-stage determination value TH2 (S157: Yes), it moves to S158 to determine the second-stage communication abnormality, and the inter-microcomputer communication abnormality is stored as a diagnosis in the storage unit 156, 256.

[0100] exist Fig. 9 In the above, S153 to S155 correspond to the diagnosis storage shielding condition judgment. When an affirmative judgment is made in S153, it has been determined that other systems have stopped, so it is judged that the diagnosis storage shielding condition related to the abnormal communication between microcomputers is established. When an affirmative judgment is made in S155, the relay of the other system is Lo, and it is considered that the communication failure is caused by the stop of other systems rather than the communication between microcomputers, and it is judged that the diagnosis storage shielding condition related to the abnormal communication between microcomputers is established. In addition, when an affirmative judgment is made in S154, since the power supply is locked and the IG is normally disconnected, it is judged that the diagnosis storage shielding condition related to the abnormal communication between microcomputers is established. When a negative judgment is made in S153 to S155, it is judged that the diagnosis storage shielding condition is not established. The order of S153 to S155 can be changed, or part of the processing can be omitted.

[0101] based on Figure 10 to Figure 13 The timing diagram of the communication is used to explain the handling of abnormal communication. Fig.10In the figure, from the upper part, the power supply state to the first control unit 150 (recorded as "IG-1" in the figure), the power supply state to the second control unit 250 (recorded as "IG-2" in the figure), the drive mode of the first system L1, the drive mode of the second system L2, the first stage communication abnormality counter Ct1, the second stage communication abnormality counter Ct2, and the other system monitoring counter Ct3 are set. In the following, the case where an abnormality occurs in the first system L1 is used as an example for explanation, and the counters Ct1, Ct2, and Ct3 are set to the values ​​in the second control unit 250. In addition, the state of supplying power to the control units 150 and 250 is set to "power on", and the state of interrupting the power supply is set to "power off". Figures 11 to 14 as well as Fig.18 It's basically the same.

[0102] Prior to the description of this embodiment, based on Fig.17 and Fig.18 The reference example is explained below. In the reference example, abnormality handling and diagnostic storage are performed simultaneously using a single counter. Fig.18 As shown, at time x90, when an abnormality of power supply interruption occurs in the first system L1, the microcomputer of the first control unit 150 stops. At this time, in the second control unit 250, an abnormality in inter-microcomputer communication is detected, and counting of the abnormality counter is started.

[0103] At time x91, when the count value of the abnormality counter reaches the determination threshold value THa, the second control unit 250 determines that the first system L1 as the target system is stopped, stores abnormality information indicating the stop of the target system as a diagnosis, and shifts from normal control to standby control.

[0104] Here, if the abnormality generated at time x90 is a power outage, if the power supply to the first system L1 is restarted, the microcomputer of the first control unit 150 is restarted at time x92. Here, at time x92, if the second system L2 has already shifted to standby control and increased output, in the restarted first control unit 150, if the motor 80 is driven in the coordinated drive mode or the independent drive mode, it may become an over-output. In addition, although it is a temporary power outage, the diagnosis of the stop of the target system is stored, so unnecessary measures such as repair and replacement of the first control unit 150 may be performed.

[0105] Therefore, in this embodiment, a two-stage determination is made, and the abnormality determination related to the change of the drive mode and the abnormality determination related to the diagnostic storage are separated, and different determination times are set. In addition, for the transition from the independent drive mode to the standby control, a total of three counters are used based on the information monitored by other systems to switch the drive mode and perform diagnostic storage.

[0106] like Fig.10As shown, when the power supply of the first system L1 is interrupted at time x10, the microcomputer of the first control unit 150 stops. In the second control unit 250, the communication abnormality between the microcomputers is detected, and the counting of the first-stage communication abnormality counter Ct1 is started. At time x11, if the first-stage communication abnormality counter Ct1 exceeds the first-stage determination judgment value TH1, the second control unit 250 switches the drive mode to the independent drive mode. In the independent drive mode, since the output characteristics are not changed, when the first system L1 stops, the output becomes 1 / 2 of the normal state. In addition, during the restart of the microcomputer of the first control unit 150, since the other system relay is Lo, the counting of the other system monitoring counter Ct3 is started. At this time, since the other system relay is Lo, the diagnostic storage shielding condition is met, and therefore the second-stage communication abnormality counter Ct2 does not count.

[0107] At time x12, if the microcomputer of the first control unit 150 is restarted, the other system relay becomes Hi, so the other system monitoring counter Ct3 is reset. In addition, if the first control unit 150 obtains information that the second system L2 is in the independent drive mode through inter-microcomputer communication, the drive control of the motor 80 is performed in the independent drive mode. In this way, it is possible to prevent the temporary stop and restart of the first control unit 150 caused by a power failure, etc. from being left in the storage unit 256 of the second control unit 250. In addition, after the first control unit 150 is restarted, the drive control of the motor 80 of the two systems is performed in the independent drive mode, so that the output reduction and over-output can be prevented.

[0108] Fig.11 This is an example of a case where the power supply of the first system L1 is turned off at time x20 and remains in the off state. Fig.10 The processing at time x10 and time x11 in is the same. If the power off state of the first system L1 is continued, the Lo of the other system relay is continued. At time x22, if the other system monitoring counter Ct3 exceeds the other system abnormality determination judgment value TH3, the second control unit 250 stores the other system stop as a diagnosis in the storage unit 256. In addition, the drive mode is switched from the independent drive mode to the single system drive mode, and the control is shifted to the standby control to change the output characteristics.

[0109] Fig.12This is an example of a case where an abnormality in inter-microcomputer communication occurs at time x30. In this example, both systems L1 and L2 are powered on, and counters Ct1, Ct2, and Ct3 have the same value in control units 150 and 250. If an abnormality in inter-microcomputer communication occurs at time x30, the counting of the first-stage communication abnormality counter Ct1 starts. At time x31, if the first-stage communication abnormality counter Ct1 exceeds the first-stage determination judgment value TH1, both systems L1 and L2 shift to the independent drive mode.

[0110] In this example, since the other systems except the inter-microcomputer communication are normal, the other system monitoring counters Ct3 are not counted. In addition, since the diagnostic storage mask condition is not satisfied, the second-stage communication abnormality counter Ct2 starts counting. At time x32, if the second-stage communication abnormality counter Ct2 exceeds the second-stage determination judgment value TH2, the control units 150 and 250 store the inter-microcomputer communication abnormality as a diagnosis in their own storage units 156 and 256, respectively. For example, since the information stored in the storage units 156 and 256 is used for fault analysis, there is no actual harm even if the diagnostic storage timing is delayed compared to the switching of the drive mode.

[0111] Fig.13 This is an example of a case where the power supply to the first system L1 is restored after the transition to the backup control. Here, the description of the time required for the restart of the first control unit 150 is omitted. Fig.16 The same is true for the processing from time x40 to time x42. Fig.11 The processing from time x20 to time x22 in is the same. At time x43, the power supply to the first system L1 returns to normal, and the first control unit 150 starts. At this time, if the first control unit 150 obtains information that the second system L2 has moved to standby control through inter-microcomputer communication, the drive control of the motor 80 based on the first system L1 is not performed, and the auxiliary stop state is set to prevent excessive assistance. In addition, since the microcomputer of the first control unit 150 is in operation, processing other than the drive control of the motor 80, such as abnormality monitoring, can also be performed. In addition, in this case, a relatively long stop of other systems occurs, and the stop of other systems is left as a diagnosis.

[0112] As described above, the ECU 10 controls the driving of the motor 80 having the motor windings 180 and 280, and includes a plurality of inverter units 120 and 220 and a plurality of control units 150 and 250. The inverter units 120 and 220 switch the energization of the motor windings 180 and 280. The control units 150 and 250 include a drive control unit 151 and 251, a mode selection unit 152 and 252, an abnormality monitoring unit 155 and 255, and a storage unit 156 and 256, and are capable of communicating with each other. The drive control unit 151 and 251 controls the inverter units 120 and 220 provided correspondingly. The mode selection unit 152 and 252 selects the drive mode. The abnormality monitoring unit 155 and 255 performs abnormality monitoring. The storage unit 156 and 256 stores the abnormality monitoring results. In addition, the combination of the inverter units 120 and 220 provided correspondingly and the control units 150 and 250 is regarded as a system.

[0113] The drive mode includes a coordinated drive mode, an independent drive mode, and a standby mode. The coordinated drive mode uses the values ​​obtained from other control units through communication and the values ​​calculated by its own control unit to control the energization of the motor winding 180 in multiple systems. The independent drive mode does not use the values ​​obtained from other control units, but controls the drive of the motor winding in a manner that becomes the same output as the output of the system when driving all systems. Here, the so-called "same output" refers to, for example, the degree of output difference caused by differences in control methods. In addition, in the independent drive mode, the number of systems used for driving is not considered. That is, if the other systems stop, it becomes an independent drive in one system, and if the other systems are also in independent drive mode, it becomes an independent drive mode in two systems. The same is true for more than three systems. In the standby mode, the values ​​obtained from other control units are not used, and the output characteristics are changed to control the energization of the motor windings 180 and 280 to compensate for the output of other systems in one system.

[0114] The mode selection unit 152, 252 sets the normal driving mode to the coordinated driving mode, and switches the driving mode from the coordinated driving mode to the independent driving mode when a communication abnormality or a synchronization abnormality, that is, an abnormality that cannot be coordinated, is detected between the control units 150, 250. In addition, after the control units 150, 250 move to the independent driving mode due to an abnormality that cannot be coordinated, when it is determined that the other system has stopped based on other system relay information obtained separately from the communication between the control units 150, 250, the driving mode is switched from the independent driving mode to the standby mode. In this way, the drive of the rotating motor can be properly controlled. In addition, the output is not increased until it is determined that the other system has stopped, so that excessive output when the other system recovers from a temporary abnormality can be prevented.

[0115] When the independent drive mode is switched to the standby mode, the control unit 150, 250 stores the abnormal information related to the stop of other systems in its own storage unit 156, 256. In other words, the abnormal information related to the stop of other systems is not stored until the standby mode is switched after it is determined that the other systems are stopped based on the other system information. Thus, for example, temporary abnormalities caused by external factors such as power failure are not stored, and the probability of storing erroneous abnormal history can be reduced.

[0116] The time from detection of the abnormality in which coordination cannot be achieved to shifting to the standby mode is set according to the time required for restarting the control units 150 and 250. This can prevent the mode from shifting to the standby mode due to a temporary abnormality such as a power failure.

[0117] When the control unit 150 or 250 is activated, the control unit 150 or 250 maintains the stop state of the own system when the other system is switched to the standby mode. This can prevent over-output caused by adding the output of the restored system after one system is switched to the standby mode.

[0118] When an uncoordinated abnormality is detected, the timing of storing abnormality information related to the uncoordinated abnormality in the storage unit 156, 256 is later than the timing of switching the drive mode to the independent drive mode. This can quickly switch the drive mode and reduce the probability of storing erroneous abnormality history.

[0119] When other control units are stopped, the control units 150 and 250 shield the determination related to the storage of the uncoordinated abnormality. Specifically, when other control units are stopped, the second stage abnormality determination time is not counted, and the abnormality information related to the uncoordinated abnormality is not stored. In this way, it is possible to avoid storing the uncoordinated state due to the stop of other systems and the normal IG disconnection as an uncoordinated abnormality.

[0120] The time from detection of the uncoordinated abnormality to storage of the abnormality related to the uncoordinated abnormality in the storage unit 156, 256 is set according to the time required for restarting the control unit 150, 250. Thus, temporary abnormalities caused by external factors such as power failure are not stored, so the probability of storing erroneous abnormality history can be reduced.

[0121] (Second Embodiment)

[0122] Figure 14 to Figure 16 The second embodiment is shown. In this embodiment, the drive mode selection process is different from the above-mentioned embodiment, so this point is mainly described. In this embodiment, even if the independent drive mode or the single system drive mode is shifted, if it can be restored to the coordinated drive mode, it is restored to the coordinated drive mode.

[0123] based on Fig.14 The flowchart of the present embodiment is used to explain the drive mode selection process. Figure 8 The processing of S101 and S102 in is the same. In the case of abnormal communication between microcomputers, it moves to S206. In addition, if the communication between microcomputers is normal and in the case of coordinated driving, it moves to S204 and continues the coordinated driving. In the case of not being in the coordinated driving, it moves to S203.

[0124] In S203, the control unit 150, 250 determines whether the coordinated recovery condition is satisfied. If it is determined that the coordinated recovery condition is satisfied (S203: Yes), the process proceeds to S204, where the drive mode is switched to the coordinated drive mode. If it is determined that the coordinated recovery condition is not satisfied (S203: No), the process proceeds to S205, where the drive mode is set to the independent drive mode. Figure 8 The processing of S107 to S114 in is the same.

[0125] In the present embodiment, the absolute value of the difference between the first current command value calculated by the first control unit 150 and the second current command value calculated by the second control unit 250, that is, the command deviation ΔI * When the current limit value Ilim1 calculated by the first control unit 150 and the second current limit value Ilim2 calculated by the second control unit 250 are both greater than the recovery determination value, it is determined that the coordination can be restored. In addition, when the steering torque Ts is less than the non-steering determination value Ts_th, it is determined that the coordination can be restored. In addition, when the vehicle speed V is less than the vehicle speed determination value V_th, it is determined that the coordination can be restored.

[0126] That is, in this embodiment, when the command deviation ΔI * When the current limit values ​​Ilim1 and Ilim2 are greater than the recovery determination value, the steering torque Ts is less than the non-steering determination value Ts_th, and the vehicle speed V is less than the vehicle speed determination value V_th, it is determined that "the coordination recovery condition is satisfied". In addition, as a supplement, after the occurrence of the coordination failure abnormality, when the inter-microcomputer communication abnormality is restored to normal, it is considered that "the coordination failure abnormality is eliminated".

[0127] based on Fig.15 and Fig.16 The timing diagram below explains how to handle communication abnormalities. Fig.15 and Fig.10In the same example of a power outage, the processing from time x50 to time x52 is the same as Fig.10 The processing at time x10 to time x12 in is the same. At time x53, if the cooperative recovery condition is satisfied, both the systems L1 and L2 switch the drive mode from the independent drive mode to the cooperative drive mode and recover to the normal control.

[0128] Fig.16 and Fig.13 This is also an example of a case where the power supply to the first system L1 is restored after the transition to the backup control. Fig.13 The processing of time x40 to time x42 in is the same. At time x63, if the power supply to the first system L1 returns to normal and the first control unit 150 is started, the communication between the microcomputers becomes normal, so the systems L1 and L2 both set the drive mode to the independent drive mode. At time x64, if the coordinated recovery condition is met, the systems L1 and L2 both switch the drive mode from the independent drive mode to the coordinated drive mode and return to normal control. At this time, the period of power supply stoppage is longer than the other system abnormality determination time corresponding to the other system abnormality determination judgment value TH3, so the diagnosis of other system stoppage is left.

[0129] In this embodiment, the mode selection unit 152, 252 sets the driving mode to the independent driving mode when the coordination failure is eliminated, and switches the driving mode from the independent driving mode to the coordinated driving mode when the coordination recovery condition is satisfied. Thus, when a part of the system is determined to be abnormal and then returns to normal, it can be appropriately restored to the coordinated driving mode. In addition, the same effect as the above embodiment is achieved.

[0130] In the above-mentioned embodiment, ECU 10 corresponds to the "rotating motor control device", motor 80 corresponds to the "rotating motor", communication abnormality between microcomputers corresponds to the "communication abnormality between control units", other system relay information corresponds to the "other system monitoring information", and the restart caused by microcomputer reset corresponds to the "restart of the control unit".

[0131] (Other Embodiments)

[0132] In the above-mentioned embodiment, the abnormality of the monitored object is an abnormality that cannot be coordinated, and the abnormality that cannot be coordinated includes an abnormality in communication between microcomputers and an abnormality in synchronization. In other embodiments, either the abnormality in communication between microcomputers or the abnormality in synchronization can be set as an abnormality that cannot be coordinated. In addition, the abnormality of the monitored object can also be set as an abnormality other than the abnormality that cannot be coordinated. In the above-mentioned embodiment, the other system monitoring information is the other system relay information. In other embodiments, the other system monitoring information can also use information other than the other system relay information that can monitor the status of other systems. In the above-mentioned embodiment, the other system relay information is directly acquired using the other system monitoring circuit. In other embodiments, the other system monitoring information can also be acquired through a communication different from the communication for sharing the control information.

[0133] In the above-mentioned embodiment, the determination timing is made different, thereby making the abnormal handling determination determination and the abnormal storage determination determination different. In other embodiments, the determination conditions other than the determination timing may also be made different, thereby making the abnormal handling determination determination and the abnormal storage determination determination different. In addition, in the above-mentioned embodiment, the abnormal handling is to move to the independent drive mode. In other embodiments, the abnormal handling may also be a handling other than the independent drive mode. In the above-mentioned embodiment, the abnormal determination time of the second stage and the other system stop determination determination time are equal. In other embodiments, the abnormal determination time of the second stage may also be different from the other system stop determination determination time.

[0134] In the second embodiment, the steering state is determined based on the steering torque. In other embodiments, the steering state may be determined not only based on the steering torque, but also based on the steering wheel speed, the motor speed, or the rack speed. In addition, in other embodiments, the steering state may be determined based on the current command value and the current detection value. When the current command value is large, the possibility of being in the steering state is high. Therefore, when the current command value is greater than the determination threshold, it is determined to be in the steering state, and when it is less than the determination threshold, it is determined to be in the non-steering state. The same is true for the current detection value. In addition, the steering state may be determined using two or more of the steering torque, the steering wheel speed, the motor speed, the rack speed, the current command value, and the current detection value.

[0135] In the second embodiment, the command deviation, the current limit value, the steering torque and the vehicle speed are used as the coordinated recovery determination condition. In other embodiments, as the coordinated recovery determination condition, part of the above four determination conditions illustrated may be omitted, or other determination conditions may be added, for example, as an item related to the behavior of the vehicle, other items such as the lateral G and yaw rate of the vehicle may be added.

[0136] In the above-mentioned embodiment, in the coordinated drive mode, the current command value, the current detection value, and the current limit value are shared between the systems. In other embodiments, the current limit value may not be shared in the coordinated drive mode. In the above-mentioned embodiment, the first control unit 150 is used as the master control unit, and the second control unit 250 is used as the slave control unit. In the coordinated drive mode, the current command value calculated by the first control unit 150 is used in the control units 150 and 250. In other embodiments, the current command value may not be shared, and the current command value of the system is used in the coordinated drive mode. In addition, values ​​other than the current command value, the current detection value, and the current limit value may be shared.

[0137] In the above-mentioned embodiment, two motor windings, two inverter parts, and two control parts are provided. In other embodiments, the motor windings may be one or more than three. In addition, there may be more than three inverter parts and control parts. In addition, for example, in the case where one control part is provided for a plurality of motor windings and inverter parts, or a plurality of inverter parts and motor windings are provided for one control part, the number of motor windings, inverter parts, and control parts may be different. In the above-mentioned embodiment, a power supply is provided for each system, and the grounding is separated. In other embodiments, one power supply may be shared by a plurality of systems. In addition, a plurality of systems may be connected to a common ground.

[0138] In the above embodiment, the rotating electric machine is a three-phase brushless motor. In other embodiments, the rotating electric machine is not limited to a brushless motor. In addition, it may be a so-called electric generator having the function of a generator. In the above embodiment, the control device is applied to an electric power steering device. In other embodiments, the control device may also be applied to a steering control device other than an electric power steering device that manages steering control, such as a steer-by-wire device. In addition, it may also be applied to a vehicle-mounted device other than a steering control device, or a device other than a vehicle-mounted device.

[0139] The control unit and method thereof described in the present disclosure may also be implemented by a special-purpose computer, which is provided by a processor and a memory programmed to execute one or more functions embodied by a computer program. Alternatively, the control unit and method thereof described in the present disclosure may also be implemented by a special-purpose computer provided by a processor composed of one or more special-purpose hardware logic circuits. Alternatively, the control unit and method thereof described in the present disclosure may also be implemented by one or more special-purpose computers, which are composed of a combination of a processor and a memory programmed to execute one or more functions, and a processor composed of one or more hardware logic circuits. In addition, the computer program may also be stored as an instruction executed by a computer in a computer-readable non-transitional tangible storage medium. As described above, the present disclosure is not limited to the above-mentioned embodiments, and can be implemented in various ways without departing from its main purpose.

[0140] The present disclosure is described based on the embodiments. However, the present disclosure is not limited to the embodiments and configurations. The present disclosure also includes various modifications and modifications within the equivalent range. In addition, various combinations and methods, further including only one element, the above, or the below other combinations and methods also belong to the scope and scope of the present disclosure.

Claims

1. A rotating electrical machine control device for controlling the driving of a rotating electrical machine having a motor winding, comprising: A plurality of inverter units for switching the energization of the motor windings; and The plurality of control units are capable of communicating with each other and include: a drive control unit for controlling the corresponding inverter unit, a mode selection unit for selecting a drive mode, an abnormality monitoring unit for performing abnormality monitoring, and a storage unit for storing abnormality information corresponding to the abnormality monitoring result. The combination of the inverter unit and the control unit provided correspondingly is regarded as a system. The above drive modes include: A coordinated drive mode controls the energization of the motor windings in a plurality of systems using values ​​obtained from other control units through communication and values ​​calculated by the control unit itself; an independent drive mode controls the energization of the motor windings in a manner that produces the same output as that of the system when driving all systems without using values ​​obtained from other control units; and a standby mode controls the energization of the motor windings by changing the output characteristics without using values ​​obtained from other control units, so as to compensate for the output of other systems in one system. The mode selection unit sets the normal driving mode to the cooperative driving mode. When an abnormality that cannot be coordinated is detected, the mode selection unit switches the driving mode from the coordinated driving mode to the independent driving mode, wherein the abnormality that cannot be coordinated is a communication abnormality between the control units or a synchronization abnormality between the control units. After the mode is shifted to the independent drive mode due to the abnormality of the inability to coordinate, the mode selection unit does not change the output characteristics until it is determined that the other system stops based on the monitoring information of the other system, and when it is determined that the other system stops based on the monitoring information of the other system, the drive mode is switched from the independent drive mode to the standby mode, and the output characteristics are changed to compensate for the output of the other system, wherein the monitoring information of the other system is the relay information of the other system obtained separately from the communication between the control unit, The time from detection of the impossible-to-coordinate abnormality to switching to the standby mode is set according to the time required for restarting the control unit.

2. The rotating electrical machine control device according to claim 1, wherein: When the independent drive mode is shifted to the standby mode, the control unit stores information related to the stop of other systems in the storage unit as the abnormality information.

3. The rotating electrical machine control device according to claim 1 or 2, wherein: When the control unit starts up, the control unit maintains the stop state of the own system when other systems shift to the standby mode.

4. The rotating electrical machine control device according to claim 1 or 2, wherein: When the coordination failure is resolved, the mode selection unit sets the drive mode to the independent drive mode, and when a coordination recovery condition is satisfied, switches the drive mode from the independent drive mode to the coordinated drive mode.

5. The rotating electrical machine control device according to claim 1 or 2, wherein: When the incoordination abnormality is detected, information related to the incoordination abnormality is stored in the storage unit as the abnormality information later than the timing of switching the drive mode to the independent drive mode.

6. The rotating electrical machine control device according to claim 5, wherein: When the other control units are stopped, the control unit masks the determination related to the storage of the incoordination abnormality.

7. The rotating electrical machine control device according to claim 5, wherein: The time from detection of the impossible-to-coordinate abnormality to storage of the abnormality related to the impossible-to-coordinate abnormality in the storage unit is set according to the time required for restarting the control unit.

8. A rotating electrical machine control device for controlling the driving of a rotating electrical machine having a motor winding, comprising: A plurality of inverter units for switching the energization of the motor windings; and The plurality of control units are capable of communicating with each other and include: a drive control unit for controlling the corresponding inverter unit, a mode selection unit for selecting a drive mode, an abnormality monitoring unit for performing abnormality monitoring, and a storage unit for storing abnormality information corresponding to the abnormality monitoring result. The combination of the inverter unit and the control unit provided correspondingly is regarded as a system. The above drive modes include: A coordinated drive mode controls the energization of the motor windings in a plurality of systems using values ​​obtained from other control units through communication and values ​​calculated by the control unit itself; an independent drive mode controls the energization of the motor windings in a manner that produces the same output as that of the system when driving all systems without using values ​​obtained from other control units; and a standby mode controls the energization of the motor windings by changing the output characteristics without using values ​​obtained from other control units, so as to compensate for the output of other systems in one system. The mode selection unit sets the normal driving mode to the cooperative driving mode. When an abnormality that cannot be coordinated is detected, the mode selection unit switches the driving mode from the coordinated driving mode to the independent driving mode, wherein the abnormality that cannot be coordinated is a communication abnormality between the control units or a synchronization abnormality between the control units. After the mode is shifted to the independent drive mode due to the abnormality of the inability to coordinate, the mode selection unit does not change the output characteristics until it is determined that the other system stops based on the monitoring information of the other system, and when it is determined that the other system stops based on the monitoring information of the other system, the drive mode is switched from the independent drive mode to the standby mode, and the output characteristics are changed to compensate for the output of the other system, wherein the monitoring information of the other system is the relay information of the other system obtained separately from the communication between the control unit, When the incoordination abnormality is detected, information related to the incoordination abnormality is stored in the storage unit as the abnormality information later than the timing of switching the drive mode to the independent drive mode.

9. The rotating electrical machine control device according to claim 8, wherein: When the other control units are stopped, the control unit masks the determination related to the storage of the incoordination abnormality.

10. The rotating electrical machine control device according to claim 8, wherein: The time from detection of the impossible-to-coordinate abnormality to storage of the abnormality related to the impossible-to-coordinate abnormality in the storage unit is set according to the time required for restarting the control unit.

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