Motor control device and electric brake device

Abstract

A motor control unit as a motor control device includes a first motor drive circuit, a second motor drive circuit, a first electronic control unit, and a second electronic control unit. The first electronic control unit and / or the second electronic control unit are / is provided with an abnormality determination unit. The abnormality determination unit determines that there is an abnormality in a second phase cut-off switch when, for example, a first inverter that drives a first motor drive circuit, cuts off the second phase cut-off switch, which is a motor cut-off switch, and cuts off a second FS cut-off switch, and when a voltage is detected by a second voltage monitor.

Description

Technical Field

[0001] This disclosure relates to motor control devices and electric braking devices. Background Technology

[0002] Patent Document 1 discloses a fault detection method for a motor control device. This fault detection method detects faults in the motor control device by monitoring the voltage detected when a voltage is supplied from a pre-charging circuit using an arithmetic processing unit.

[0003] Prior technology documents

[0004] Patent documents

[0005] Patent Document 1: International Publication No. 2019 / 187529 Summary of the Invention

[0006] The problem that the invention aims to solve

[0007] The fault detection method in Patent Document 1 can detect faults in both the switching element of the motor cut-off switch (motor cut-off FET) and the switching element on the high side of the inverter (upper-side FET), i.e., a double fault. However, it cannot detect faults in the motor cut-off switch (motor cut-off FET) alone.

[0008] One of the objectives of this invention is to provide a motor control device and an electric brake capable of detecting a single malfunction in a motor cut-off switch.

[0009] Methods for solving problems

[0010] An embodiment of the present invention relates to a motor control device comprising: a plurality of motor drive circuits connected between a motor having multiple stator winding systems and a power supply, capable of independently energizing each system of the stator windings of the motor; and a plurality of control units controlling the energizing of the motor drive circuits. Each of the plurality of motor drive circuits comprises: an inverter disposed between the motor and the power supply; a measuring unit measuring the voltage or current of the inverter; a motor cut-off switch cutting off the power supply from the inverter to the motor; and a power cut-off switch cutting off the power supply from the power supply to the inverter. The control units include an anomaly determination unit that, when driving the motor drive circuit of one system and cutting off the motor cut-off switch and the power cut-off switch of other systems, determines that the motor cut-off switch of the other system is abnormal when the measuring unit of the other system detects voltage or current.

[0011] Furthermore, an electric braking device according to one embodiment of the present invention includes: a motor having a stator winding having a plurality of systems; and a motor control device, wherein the electric braking device is disposed in a vehicle and drives the motor to press a braking member toward a braked member, the motor control device comprising:

[0012] Multiple motor drive circuits are connected between the motor and the power supply, enabling independent energization of each system of the motor's stator windings; and multiple control units control the energization to the motor drive circuits. Each of the multiple motor drive circuits includes: an inverter disposed between the motor and the power supply; a measuring unit that measures the voltage or current of the inverter; a motor cut-off switch that cuts off the power supply from the inverter to the motor; and a power cut-off switch that cuts off the power supply from the power supply to the inverter. The control unit has an anomaly determination unit that, when driving the motor drive circuit of one system and cutting off the motor cut-off switch and the power cut-off switch of other systems, determines that the motor cut-off switch of the other system is abnormal when the measuring unit of the other system detects voltage or current.

[0013] According to one embodiment of the present invention, it is possible to detect a fault occurring solely in the motor shut-off switch. Attached Figure Description

[0014] Figure 1 This is a cross-sectional view showing an electric brake including an embodiment of a motor control device.

[0015] Figure 2 It is a block diagram representing the motor control device and the motor.

[0016] Figure 3 This is an example of the state when judging an abnormality of the switch used to cut off the motor. Figure 2 The same block diagram.

[0017] Figure 4 It is a circuit diagram representing the motor control device and the motor.

[0018] Figure 5 It means Figure 4 The circuit diagram of the upper part of the circuit.

[0019] Figure 6 It means Figure 4 The circuit diagram for the lower half of the circuit.

[0020] Figure 7 This is an example of the state when judging an abnormality of the switch used to cut off the motor. Figure 4 The same circuit diagram.

[0021] Figure 8 This is a characteristic curve diagram showing the time variation of the inverter power supply voltage when the motor disconnection switch is in normal and abnormal (fault) conditions. Detailed Implementation

[0022] The following description will be based on the example of mounting the motor control device and electric brake of the embodiment on a four-wheeled vehicle, with reference to the accompanying drawings.

[0023] exist Figure 1 and Figure 2 In this context, the braking system 1 installed in a vehicle (automobile) comprises: an electric brake 2 ( Figure 1 ), and through the drive of brake motor 4, apply braking force to the wheels (not shown) of the vehicle; and the upper control device 35 ( Figure 2 This serves as the vehicle controller. In this embodiment, the higher-level control device 35 corresponds, for example, to the integrated controller (integrated ECU) that determines the vehicle's motion control. Hereinafter, the higher-level control device 35 will be referred to as the integrated control device 35. Alternatively, as described later, the higher-level control device 35 may also be a brake control device (brake ECU) that controls the electric brakes 2 of each of the four wheels of the vehicle.

[0024] Electric brakes 2 are mounted on each wheel of a vehicle with multiple wheels. For example, in a four-wheeled car, a total of four electric brakes 2 are installed, corresponding to the left front wheel, right front wheel, left rear wheel, and right rear wheel respectively. Thus, the braking system 1 can independently control the braking force on each wheel (left front wheel, right front wheel, left rear wheel, right rear wheel). Furthermore, in Figure 1 The image shows one electric brake 2; the remaining three electric brakes are omitted. The remaining three electric brakes are also... Figure 1 The electric brake 2 is the same as that of the integrated control unit 35.

[0025] like Figure 1 As shown, the electric brake 2 has a motor assembly 3 and a braking mechanism 41. The motor assembly 3 includes a brake motor 4 as a motor (electric motor) and a motor control unit 9 as a motor controller. The brake motor 4 drives the braking mechanism 41 to apply braking force to the vehicle. The motor control unit 9 controls the brake motor 4. Figure 2 As shown, the motor control unit 9 includes motor drive circuits 10 and 20 (first motor drive circuit 10 and second motor drive circuit 20) that serve as motor drive units and electronic control units 11 and 21 (first electronic control unit 11 and second electronic control unit 21) that serve as motor control units.

[0026] like Figure 1As shown, the braking mechanism 41 corresponds, for example, to an electric disc brake in which the brake pad 45 is pressed against the disc rotor D by the brake motor 4. The braking mechanism 41 includes a planetary carrier 42, a brake caliper 43 as a cylinder (wheel cylinder), a piston 44 as a pressing member, and a brake pad 45 as a braking member (friction block). To drive the braking mechanism 41, i.e., to generate braking force, a brake motor 4, which is an electric motor, is installed in the braking mechanism 41. Furthermore, the braking mechanism 41 includes a reduction gear 46 and a rotary-to-direct-drive conversion mechanism 47.

[0027] The planetary carrier 42 is fixed to the side of the vehicle body. The brake caliper 43 is supported (floating support) on the carrier 42 in a manner that allows it to move axially along the disc rotor D. The piston 44 is propelled by the brake motor 4. That is, the brake motor 4 rotates by an electrical supply, propelling the piston 44 via a reduction mechanism 46 and a rotary-to-direction conversion mechanism 47. The reduction mechanism 46, for example, is a gear reduction mechanism that reduces the rotation of the brake motor 4 and transmits it to the rotary-to-direction conversion mechanism 47. The rotary-to-direction conversion mechanism 47 converts the rotation of the brake motor 4 transmitted via the reduction mechanism 46 into an axial displacement (direct displacement) of the piston 44. The rotary-to-direction conversion mechanism 47 is, for example, a ball screw. That is, in this embodiment, the rotary-to-direction conversion mechanism 47 includes a rotating member 47A of a rod-shaped body with ball grooves formed on its outer peripheral side and a cylindrical direct-acting member 47B that serves as a propulsion member and has ball grooves formed on its inner peripheral side. Multiple balls are provided between the ball groove of the rotating component 47A and the ball groove of the linear component 47B.

[0028] Piston 44 is propelled by brake motor 4, causing brake block 45 to move. Brake block 45 is pressed against disc rotor D by piston 44. A pair of brake blocks 45 are located on opposite sides of the disc rotor D along its axial direction and are supported by gear carrier 42. Disc rotor D, as the braked component (rotor), rotates together with the wheel. Braking mechanism 41 transmits the thrust generated by the brake motor 4 to piston 44, which moves brake block 45. Thus, braking mechanism 41 presses brake block 45 against disc rotor D.

[0029] Furthermore, the electric brake 2 is not limited to an electric disc brake; for example, it can also be an electric drum brake that applies braking force by pressing the shoe against the drum using a motor (electric motor). Additionally, the electric brake can also be a hydraulic disc brake equipped with a motor (electric motor) (a hydraulic disc brake with electric parking brake function), or a cable-operated electric parking brake that applies the parking brake by pulling a cable using a motor (electric motor). In other words, the electric brake corresponds to various electric brakes that apply and release braking force (hold and release the pressing force) by pressing (pushing) the friction component (shoe) against the rotating component (rotor, drum) based on the drive of a motor (electric motor, electric actuator).

[0030] like Figure 2 As shown, the brake motor 4 comprises a stator 5 forming the stator and a rotor 6 forming the permanent magnet rotor, the rotor 6 being rotatably disposed at the center of the stator 5. The rotor 6 of the brake motor 4 rotates the rotating component 47A of the rotary-to-linear conversion mechanism 47 via the reduction mechanism 46 of the brake mechanism 41. That is, the rotation of the brake motor 4 (rotor 6) is converted by the rotary-to-linear conversion mechanism 47 into the linear motion of the linear component 47B, causing the brake block 45 of the brake mechanism 41 to approach and separate relative to the disc rotor D.

[0031] To ensure redundancy, the brake motor 4 has two winding groups 7 and 8. That is, the brake motor 4 is configured as a dual 3-phase synchronous motor, which has a first winding group 7 consisting of a star-connected 3-phase winding U1, V1, W1, and a second winding group 8 consisting of a similarly star-connected 3-phase winding U2, V2, W2. In other words, the brake motor 4 is configured as a 6-phase motor with 3-phase double windings (6-phase PMSM: a 6-phase permanent magnet synchronous motor that generates torque through 3-phase coils in two systems). The first winding group 7 and the second winding group 8 are arranged in a mutually insulated state on the stator 5.

[0032] The motor control unit 9, acting as a motor control device, controls the brake motor 4. Specifically, the motor control unit 9 drives and controls each winding U1, V1, W1 of the first winding group 7 and each winding U2, V2, W2 of the second winding group 8 of the brake motor 4. Therefore, the motor control unit 9 includes a first drive control system (first motor drive circuit 10, first electronic control unit 11) for driving and controlling the first winding group 7 (U1, V1, W1) and a second drive control system (second motor drive circuit 20, second electronic control unit 21) for driving and controlling the second winding group 8 (U2, V2, W2).

[0033] That is, the motor control unit 9 includes a first motor drive circuit 10, a first electronic control unit 11, a second motor drive circuit 20, and a second electronic control unit 21. Furthermore, the first drive control system of the motor control unit 9 is also referred to as the "first system," "main channel," or "ECU1 side." Similarly, the second drive control system of the motor control unit 9 is also referred to as the "second system," "secondary channel," or "ECU2 side." In other words, the first drive control system of the motor control unit 9, including the first motor drive circuit 10 and the first electronic control unit 11, constitutes the first ECU. The second drive control system of the motor control unit 9, including the second motor drive circuit 20 and the second electronic control unit 21, constitutes the second ECU.

[0034] The first motor drive circuit 10 drives the brake motor 4. The first motor drive circuit 10 is configured to include a first inverter 12 as a first bridge circuit section. The first inverter 12 is configured to include multiple switching elements composed of transistors such as field-effect transistors (FETs) and insulated-gate bipolar transistors (IGBTs). For example, as described later... Figure 4 and Figure 5 As shown, the first inverter 12 includes a first inverter circuit 12A, which is a first bridge circuit (3-phase bridge inverter) composed of six switching elements (FETs: field-effect transistors), and a first FET drive circuit 12B that drives the first inverter circuit 12A.

[0035] The switching of each switching element (i.e., each FET of the first inverter circuit 12A) in the first inverter 12 is controlled based on command signals from the first electronic control unit 11. Therefore, the first electronic control unit 11 and the first inverter 12 are connected via the first signal line 13. When the brake motor 4 is driven, the first inverter 12 generates three-phase (U-phase, V-phase, W-phase) AC power based on the command signals from the first electronic control unit 11 and supplies the AC power to the first winding group 7 (windings U1, V1, W1) of the brake motor 4.

[0036] The first inverter 12 of the first motor drive circuit 10 is connected to the vehicle's first power source 31, such as an energy storage device (battery), via the first DC power line 14. In this case, a first fail-safe switch 15 (hereinafter referred to as the first FS disconnect switch 15) is provided between the first inverter 12 (first inverter circuit 12A) and the first power source 31. Figure 4 and Figure 5 As shown, the first FS cut-off switch 15 is composed of, for example, a switching element 15A and a FET driving circuit 15B. The switching element 15A is composed of a field-effect transistor (FET), and the FET driving circuit 15B drives the switching element 15A.

[0037] Additionally, the first inverter 12 (first inverter circuit 12A) of the first motor drive circuit 10 is connected to the brake motor 4. In this case, the first inverter 12 (first inverter circuit 12A) is connected to the windings U1, V1, and W1 of the first winding group 7 of the brake motor 4 via the U1 phase power line 16, V1 phase power line 17, and W1 phase power line 18. A first phase cutoff switch 19 is provided between the first inverter 12 (first inverter circuit 12A) and the brake motor 4 (first winding group 7). Figure 4 and Figure 5 As shown, the first phase disconnect switch 19 is composed, for example, of three switching elements 19A, each including a field-effect transistor (FET), and a FET driving circuit 19B that drives the three switching elements 19A.

[0038] The first electronic control unit 11 is connected to the first motor drive circuit 10. Together, the first electronic control unit 11 and the first motor drive circuit 10 constitute the first ECU. The first electronic control unit 11 is configured as a microcomputer including an arithmetic circuit (CPU). The first electronic control unit 11 is connected to the vehicle's first power supply 31 via a first DC power line 14 and to the first motor drive circuit 10 (first inverter 12) via a first signal line 13. The first electronic control unit 11 drives the brake motor 4 (forward or reverse rotation) by controlling the first motor drive circuit 10 (first inverter 12) (switching control, more specifically, PWM control). That is, the first electronic control unit 11 drives the first inverter circuit 12A via the first FET drive circuit 12B of the first inverter 12 (switching control), thereby driving the brake motor 4 (forward or reverse rotation).

[0039] The second motor drive circuit 20 also drives the brake motor 4 in the same way as the first motor drive circuit 10. The second motor drive circuit 20 is configured to include a second inverter 22 as a second bridge circuit section. The second inverter 22 is also configured, like the first inverter 12, to include multiple switching elements composed of transistors such as field-effect transistors (FETs) and insulated-gate bipolar transistors (IGBTs). For example, as described later... Figure 4 and Figure 6 As shown, the second inverter 22 also includes a second inverter circuit 22A, which is a second bridge circuit (3-phase bridge inverter) composed of six switching elements (FETs: field-effect transistors), and a second FET drive circuit 22B that drives the second inverter circuit 22A.

[0040] The switching elements (i.e., the FETs of the second inverter circuit 22A) of the second inverter 22 are controlled to open / close based on command signals from the second electronic control unit 21. Therefore, the second electronic control unit 21 and the second inverter 22 are connected via the second signal line 23. When the brake motor 4 is driven, the second inverter 22 generates three-phase (U-phase, V-phase, W-phase) AC power from DC power based on command signals from the second electronic control unit 21, and supplies this AC power to the second winding group 8 (windings U2, V2, W2) of the brake motor 4.

[0041] The second inverter 22 of the second motor drive circuit 20 is connected to the vehicle's second power supply 32, such as an energy storage device (battery), via the second DC power line 24. The second power supply 32 is a different power supply (power supply of a different system) from the first power supply 31 connected to the first motor drive circuit 10 and the first electronic control unit 11. In this way, redundancy is ensured by setting the power supply path to a dual system.

[0042] A second fail-safe switch 25 (hereinafter referred to as the second FS disconnect switch 25) is provided between the second inverter 22 (second inverter circuit 22A) and the second power supply 32. Figure 4 and Figure 6 As shown, the second FS cut-off switch 25 is composed, for example, a switching element 25A including a field-effect transistor (FET) and a FET driving circuit 25B that drives the switching element 25A.

[0043] Additionally, the second inverter 22 (second inverter circuit 22A) of the second motor drive circuit 20 is connected to the brake motor 4. In this case, the second inverter 22 (second inverter circuit 22A) is connected to the windings U2, V2, and W2 of the second winding group 8 of the brake motor 4 via the U2 phase power line 26, V2 phase power line 27, and W2 phase power line 28. A second phase cutoff switch 29 is provided between the second inverter 22 (second inverter circuit 22A) and the brake motor 4 (second winding group 8). Figure 4 and Figure 6 As shown, the second phase cut-off switch 29 is composed, for example, of three switching elements 29A each composed of field-effect transistors (FETs) and a FET driving circuit 29B that drives the three switching elements 29A.

[0044] The second electronic control unit 21 is connected to the second motor drive circuit 20. Together, the second electronic control unit 21 and the second motor drive circuit 20 constitute the second ECU. The second electronic control unit 21 is configured as a microcomputer including an arithmetic logic unit (CPU). The second electronic control unit 21 is connected to the vehicle's second power supply 32 via the second DC power line 24 and to the second motor drive circuit 20 (second inverter 22) via the second signal line 23. The second electronic control unit 21 drives the brake motor 4 (forward or reverse rotation) by controlling the second motor drive circuit 20 (second inverter 22) (switching control, more specifically PWM control). That is, the second electronic control unit 21 drives the second inverter circuit 22A via the second FET drive circuit 22B of the second inverter 22 (switching control), thereby driving the brake motor 4 (forward or reverse rotation).

[0045] A rotation angle sensor 30 for feedback control of the rotation of the rotor 6 of the brake motor 4 is connected to the first electronic control unit 11 and the second electronic control unit 21. The rotation angle sensor 30, as a rotation position detection unit, is provided in the brake motor 4 to detect the rotational position (e.g., rotation angle) of the rotor 6 of the brake motor 4. The rotation angle sensor 30 is, for example, a magnetic sensor such as a GMR sensor. In this case, the rotation angle sensor 30 may be composed of, for example, a magnetic sensor element (GMR) provided on the stator 5 side of the brake motor 4 and a rotation angle detection magnet provided on the rotor 6 side of the brake motor 4. Alternatively, to ensure redundancy, a structure in which two rotation angle sensors are provided in the brake motor 4 may be formed. In this case, a first rotation angle sensor (magnetic sensor element), which can become one of the rotation angle sensors, is connected to the first electronic control unit 11, and a second rotation angle sensor (magnetic sensor element), which is a different rotation angle sensor from the first rotation angle sensor, is connected to the second electronic control unit 21.

[0046] The first electronic control unit 11 and the second electronic control unit 21 are interconnected via a communication line 33 (inter-CPU communication line). Additionally, a vehicle data bus 34 connects the motor control unit 9 (the first electronic control unit 11 and the second electronic control unit 21) as a communication line. The vehicle data bus 34, for example, constitutes a CAN (Controller Area Network) communication network mounted on the vehicle body. Various electronic devices mounted on the vehicle, such as the motor control unit 9, the integrated control unit 35, the suspension control unit (not shown), the steering control unit (not shown), and other various ECUs (Electronic Control Units), perform multiple communications within the vehicle via the vehicle data bus 34. Various communication standards, such as CAN (Classic CAN) and CAN FD (CAN with Flexible Data Rate), can be used as the communication standard.

[0047] The integrated control unit 35 is connected to the first electronic control unit 11 and the second electronic control unit 21. Specifically, the integrated control unit 35 is connected to the first electronic control unit 11 and the second electronic control unit 21 via the vehicle data bus 34. In this case, the integrated control unit 35 can be connected to the first electronic control unit 11 and the second electronic control unit 21 using different systems. That is, the connection between the integrated control unit 35 and the first electronic control unit 11 and between the integrated control unit 35 and the second electronic control unit 21 can be established via different communication lines 34A and 34B, respectively.

[0048] The integrated control unit 35 is, for example, an integrated control unit (integrated ECU) that determines vehicle motion control for moving the vehicle relative to a target trajectory obtained from the automatic driving control unit (automatic driving ECU). The integrated control unit 35 is also called the main control unit (main ECU), corresponding to the control unit (ECU) superior to the motor control unit 9 (electronic control units 11, 21). The integrated control unit 35 is also configured to include a microcomputer that serves as an arithmetic circuit (CPU).

[0049] The integrated control unit 35 can be configured as a dual-core (dual-circuit) system, for example, to perform the same processing in parallel and monitor whether there are any differences in the processing results. For example, the integrated control unit 35 consists of two control units (a first main ECU and a second main ECU), and they can be connected to each other via a communication line (inter-CPU communication line). For example, when applying braking force to the vehicle, the integrated control unit 35 outputs a command for the target motor torque (or braking force, piston thrust, motor control current value) to the motor control unit 9 (electronic control units 11, 21).

[0050] Furthermore, in this embodiment, the integrated control device 35 is an integrated ECU that has both the function of a vehicle control ECU for vehicle control and the function of a brake control ECU for braking. However, it is not limited to this; a vehicle control device corresponding to the vehicle control ECU and a brake control device corresponding to the brake ECU may be configured separately, and the brake control device (brake ECU) may be connected to the motor control unit 9 (electronic control units 11, 21) via a communication line. In this case, the brake control device (brake ECU) receives vehicle information transmitted via CAN from other ECUs mounted in the vehicle (e.g., prime mover ECU, transmission ECU, steering ECU, automatic driving ECU, etc., not shown).

[0051] For example, the brake control unit (brake ECU) obtains various vehicle information via CAN, including the position of the AT or MT gear, ignition on / off information, engine speed information, powertrain torque information, gear ratio information, steering wheel operation information, clutch operation information, accelerator operation information, vehicle-to-vehicle communication information, information about the vehicle's surroundings from onboard cameras, and information from acceleration sensors (front-to-rear acceleration, lateral acceleration), etc. Based on the driver's accelerator and brake pedal operations, or acceleration / deceleration commands (requests) from the vehicle control unit (vehicle control ECU) used for AD (autonomous driving) and ADAS (advanced driver assistance systems), the brake control unit (brake ECU) applies braking force commands to each wheel, performing service braking / slip control / vehicle attitude control.

[0052] However, the technology in Patent Document 1 described above cannot detect individual faults in the phase cut-off switch (motor cut-off switch). That is, according to the prior art, ON sticking of the phase cut-off switch element is an inconspicuous fault, and it is impossible to detect a fault (ON sticking) occurring solely in the phase cut-off switch element. Therefore, after a fault (ON sticking) in the phase cut-off switch element, when a fault (ON sticking) occurs in the inverter's switching element (e.g., MOSFET: Metal-Oxide-Semiconductor Field-Effect Transistor), i.e., when a double fault occurs, dynamic braking occurs. Furthermore, for example, if it is an electric steering system equipped with a 6-phase motor, the driver's steering energy is deprived by the dynamic brake, potentially preventing the attainment of the desired steering speed. Additionally, if it is an electric brake system equipped with, for example, a 6-phase motor, the motor output on the normal side is deprived by the dynamic brake, potentially preventing the attainment of the desired braking responsiveness.

[0053] Therefore, in this implementation, it is possible to detect a single fault (ON sticking) in the switching element of the phase disconnect switch. Specifically, the motor control device of the redundant system connected to the 6-phase motor is divided into a drive side and a diagnostic side. The motor is operated on the drive side, and fault diagnosis is performed on the diagnostic side (monitoring the voltage generated during a fault), thereby detecting a single fault (ON sticking) in the switching element of the phase disconnect switch. That is, the function of the motor control device, which has a control unit and drive circuit of two systems, is divided into a drive side (one system) and a diagnostic side (the other system). Then, with each switching element (the switching element of the phase disconnect switch, the switching element of the inverter, and the switching element of the FS disconnect switch) on the diagnostic side (the other system) set to OFF, the motor is driven (operated) on the drive side (one system). At this time, the induced voltage generated on the diagnostic side (the other system) is detected by a voltage monitor (inverter power supply voltage monitor), and it is determined whether the switching element of the phase disconnect switch on the diagnostic side (the other system) has a single fault (ON sticking).

[0054] Below, except Figure 1 and Figure 2 In addition, refer to Figures 3 to 8 These points will be explained in detail. Additionally, Figure 2 This is a block diagram of the motor control device (motor control unit 9) and the motor (brake motor 4). Figure 4 This is a circuit diagram of the motor control device (motor control unit 9) and the motor (brake motor 4). Additionally, Figure 5 Corresponding to Figure 4 The upper part (the first system and the motor). Figure 6 Corresponding to Figure 4 The lower half (second system and motor). Furthermore, Figure 3 and Figure 7 This indicates the fault status of the motor cut-off switch (second phase cut-off switch 29) of the second system, which is used to drive the motor (brake motor 4) of the first system.

[0055] like Figure 1 and Figure 2As shown, the electric brake 2 controls the motor drive circuits 10 and 20 via electronic control units 11 and 21, thereby driving the brake motor 4, which is a multi-phase motor (6-phase synchronous motor). The rotational torque of the brake motor 4 is amplified by the reduction mechanism 46 of the brake mechanism 41 and converted into thrust by the rotary direct-acting conversion mechanism 47, thereby pressing the brake block 45, which acts as a friction block, against the disc rotor D. Thus, braking force is generated in the electric brake 2. The electric brake 2 is connected to the integrated control unit 35 (main ECU, brake ECU) mounted on the vehicle via the vehicle data bus 34, which constitutes a communication mechanism such as CAN. Based on the thrust command from the integrated control unit 35, the electric brake 2 controls the position of the brake block 45 or the thrust (pressing force) of the brake block 45 to generate the desired braking torque.

[0056] Furthermore, the electric brake 2 also functions as a parking brake (PKB). For example, the electric brake 2 maintains thrust even when there is no power supply to the brake motor 4 through internal mechanisms (such as ratchet mechanisms, non-reverse reduction gears, rotary-to-direction conversion mechanisms, etc.). In this embodiment, the electric brake 2 is described as an electric disc brake. That is, the braking mechanism 41 constituting the electric brake 2 is a disc brake. However, it is not limited to this; the braking mechanism 41 can also be a drum brake, where the braking component is a shoe and the braked component is a drum.

[0057] Furthermore, in this embodiment, the motor unit 3, consisting of a multi-phase motor (brake motor 4) and a motor control device (motor control unit 9), drives and controls the braking mechanism 41, such as a disc brake or drum brake. However, it is not limited to this; the motor unit 3 can also drive and control the steering mechanism. That is, the motor unit 3 can also be combined with the steering mechanism to form an electric power steering system. In other words, the motor unit 3, by combining with driven mechanisms such as braking mechanisms and steering mechanisms, can form various electric devices (electric actuators).

[0058] The electric brake 2 has a motor unit 3 with multiple systems (redundant structure) so that braking can continue even in the event of temporary failure. That is, the motor unit 3 includes a brake motor 4 and a motor control unit 9, and the motor control unit 9 includes motor drive circuits 10 and 20 and electronic control units 11 and 21. In this case, the brake motor 4, the motor drive circuits 10 and 20, and the electronic control units 11 and 21 each have multiple systems (first system, second system).

[0059] That is, such as Figure 2 and Figure 4As shown, the brake motor 4 is a multiphase motor (6-phase motor) with two stator winding systems (first winding group 7, second winding group 8) relative to a single motor, and each stator winding (first winding group 7, second winding group 8) drives a rotor (rotor 6). Furthermore, in the motor control unit 9, a first electronic control unit 11 and a second electronic control unit 21 are installed as dual-system electronic control units, and a first motor drive circuit 10 and a second motor drive circuit 20 are installed as dual-system motor drive circuits. The first electronic control unit 11 and the second electronic control unit 21 are connected via a communication line 33, which serves as a communication unit for serial communication, etc. Thus, the first electronic control unit 11 and the second electronic control unit 21 can mutually acquire the status (information, data) of each system.

[0060] The first electronic control unit 11 and the second electronic control unit 21 calculate the three-phase voltage command based on a known current feedback control method, and perform D / A conversion through units such as PWM, thereby outputting the three-phase PWM signal as the command signal to the first motor drive circuit 10 and the second motor drive circuit 20. The first motor drive circuit 10 includes a first inverter 12, a first FS disconnect switch 15, a first phase disconnect switch 19, a first phase current monitoring circuit 61, and a first inverter power supply voltage monitor 63 (hereinafter referred to as the first voltage monitor 63) as a measurement unit (first measurement unit). In addition, the second motor drive circuit 20 includes a second inverter 22, a second FS disconnect switch 25, a second phase disconnect switch 29, a second phase current monitoring circuit 62, and a second inverter power supply voltage monitor 64 (hereinafter referred to as the second voltage monitor 64) as a measurement unit (second measurement unit).

[0061] In addition, such as Figure 4 As shown, a first inverter circuit 12A and a first FET drive circuit 12 constituting a first inverter 12 are installed in the first motor drive circuit 10, and a second inverter circuit 22A and a second FET drive circuit 22B constituting a second inverter 22 are installed in the second motor drive circuit 20. The first FET drive circuit 12B drives the first inverter circuit 12A based on a 3-phase PWM signal (command signal) from the first electronic control unit 11. The second FET drive circuit 22B drives the second inverter circuit 22A based on a 3-phase PWM signal (command signal) from the second electronic control unit 21. The first inverter circuit 12A and the second inverter circuit 22A are 3-phase bridge circuits composed of switching elements such as FETs.

[0062] The high-side of the first inverter circuit 12A is connected to the positive terminal of the first power supply 31, which serves as the vehicle's 12V battery. The high-side of the second inverter circuit 22A is connected to the positive terminal of the second power supply 32, which also serves as the vehicle's 12V battery. The low-sides of both the first and second inverter circuits 12A are grounded and connected to the negative terminal. In the first inverter circuit 12A, the switching elements on the high-side and low-side of the three phases (UVW phases) are connected in series to apply voltage to the output terminals 51, 52, and 53. The same applies to the second inverter circuit 22A. The output terminals 51, 52, and 53 of the first inverter circuit 12A are connected to the first winding group 7 (windings U1, V1, and W1) of the brake motor 4 via the U1 phase power line 16, V1 phase power line 17, and W1 phase power line 18. The output terminals 51, 52, and 53 of the second inverter circuit 22A are connected to the second winding group 8 (each winding U2, V2, and W2) of the brake motor 4 via the U2 phase power line 26, the V2 phase power line 27, and the W2 phase power line 28.

[0063] A first phase current monitoring circuit 61 is installed between the output terminals 51, 52, and 53 of the first inverter circuit 12A and the windings U1, V1, and W1 of the first winding group 7, so as to measure the three-phase current flowing through each winding U1, V1, and W1. The first phase current monitoring circuit 61 is connected to the first electronic control unit 11. The first electronic control unit 11 can monitor the phase current of the first motor drive circuit 10 through the first phase current monitoring circuit 61. Similarly, a second phase current monitoring circuit 62 is also installed between the output terminals 51, 52, and 53 of the second inverter circuit 22A and the windings U2, V2, and W2 of the second winding group 8, so as to measure the three-phase current flowing through each winding U2, V2, and W2.

[0064] Furthermore, a first phase disconnect switch 19 is installed between the output terminals 51, 52, and 53 of the first inverter circuit 12A and each winding U1, V1, and W1 of the first winding group 7. That is, the first phase disconnect switch 19 is provided on the U1 phase power line 16, V1 phase power line 17, and W1 phase power line 18. The first phase disconnect switch 19 includes switching elements 19A respectively provided on the U1 phase power line 16, V1 phase power line 17, and W1 phase power line 18, and a FET drive circuit 19B that drives these switching elements 19A. In the event of a short circuit (ON sticking) of any of the switching elements in the first inverter circuit 12A, the first phase disconnect switch 19 prevents dynamic braking from occurring in the brake motor 4.

[0065] That is, in the event of a short circuit (ON sticking) in any of the switching elements of the first inverter circuit 12A, the coil (winding) in the brake motor 4 becomes a closed circuit, generating dynamic braking that slows down the rotational motion due to Joule losses associated with coil heating caused by power generation. To prevent this, the switching element 19A of the first phase disconnect switch 19 is controlled to be turned on / off (ON / OFF) via the FET drive circuit 19B according to a signal from the first electronic control unit 11. Similarly, a second phase disconnect switch 29 is also installed between the output terminals 51, 52, 53 of the second inverter circuit 22A and the windings U2, V2, W2 of the second winding group 8. The second phase disconnect switch 29 includes switching elements 29A respectively provided on the U2 phase power line 26, V2 phase power line 27, and W2 phase power line 28, and FET drive circuits 29B that drive these switching elements 29A.

[0066] Additionally, a first FS disconnect switch 15 for switching the power supply from the first power source 31 to the first inverter circuit 12A is installed in the first motor drive circuit 10. That is, the first FS disconnect switch 15 is provided between the first power source 31 and the first inverter circuit 12A. The first FS disconnect switch 15 includes a switching element 15A disposed between the first power source 31 and the first inverter circuit 12A, and a FET drive circuit 15B for driving the switching element 15A. The switching element 15A of the first FS disconnect switch 15 is controlled to be switched on / off via the FET drive circuit 15B according to a signal from the first electronic control unit 11.

[0067] For example, in the event of a short circuit fault in the first inverter circuit 12A of the first motor drive circuit 10, the first electronic control unit 11 sets all switching elements 19A of the first phase disconnect switch 19 to OFF, sets the switching element 15A of the first FS disconnect switch 15 to OFF, and sets all switching elements of the first inverter circuit 12A to OFF. This cuts off the return current flowing in the first motor drive circuit 10 and the first winding group 7 of the brake motor 4. That is, while the generation of dynamic braking is suppressed by the first system, the brake motor 4 can be driven using only the second system to generate thrust in the brake block 45. Similarly, a second FS disconnect switch 25 is installed in the second motor drive circuit 20. The second FS disconnect switch 25 includes a switching element 25A disposed between the second power supply 32 and the second inverter circuit 22A, and a FET drive circuit 25B that drives the switching element 25A.

[0068] Additionally, a first voltage monitor 63 is installed in the first motor drive circuit 10 to detect the voltage of the first inverter circuit 12A. That is, the first voltage monitor 63 is provided between the first power supply 31 and the first inverter circuit 12A. The first voltage monitor 63, serving as an inverter power supply voltage monitor for the first system, is connected to the first electronic control unit 11. The first voltage monitor 63 detects the voltage of the first inverter circuit 12A used for motor current control. Furthermore, as described later, the first voltage monitor 63 detects the induced voltage generated in the first winding group 7, which is the diagnostic side, during the ON-sticking diagnosis of the first phase disconnect switch 19 (switching element 19A). Similarly, a second voltage monitor 64 is installed in the second motor drive circuit 20 to detect the voltage of the second inverter circuit 22A. The second voltage monitor 64, serving as an inverter power supply voltage monitor for the second system, detects the voltage of the second inverter circuit 22A used for motor current control. Furthermore, as described later, the second voltage monitor 64 detects the induced voltage generated in the second winding group 8, which is the diagnostic side, during the ON-sticking diagnosis of the second phase disconnect switch 29 (switching element 29A).

[0069] A rotation angle sensor 30 is installed on the brake motor 4. The rotation angle sensor 30 may be, for example, a magnetic rotation angle sensor such as a GMR sensor. However, it is not limited to this; the rotation angle sensor 30 may also use an optical or magnetic encoder, a resolver, etc. That is, the rotation angle sensor 30 only needs to be able to detect the electrical angle representing the magnetic pole position of the rotor (rotor 6) or the mechanical angle representing the position of the rotor (rotor 6), and various rotation sensors capable of detecting these can be used. Furthermore, the rotation angle sensor 30 may be installed in each system of the multi-system motor device 3, or only one may be installed in the multi-system motor device 3. In this embodiment, only one rotation angle sensor 30 is installed in the motor device 3.

[0070] The rotation angle sensor 30 is connected to the first electronic control unit 11. The first electronic control unit 11 converts the signal from the rotation angle sensor 30 into a digital value and uses it as a mechanical angle signal. The mechanical angle signal is converted into an electrical angle signal through internal software processing of the first electronic control unit 11. Additionally, the first electronic control unit 11 converts the three-phase current signal (the three-phase current flowing through each winding U1, V1, and W1) measured by the first phase current monitoring circuit 61 into a digital value and sets it as a three-phase current signal. The first electronic control unit 11 performs a three-phase to two-phase conversion on this three-phase current signal and performs coordinate transformation on the current signal using the electrical angle signal measured by the rotation angle sensor 30. The first electronic control unit 11 calculates the three-phase voltage command by performing current feedback control and sets it as a three-phase PMW signal. The rotation angle sensor 30 is also connected to the second electronic control unit 21. The second electronic control unit 21 performs the same processing as the first electronic control unit 11.

[0071] Here, in the implementation method, such as Figure 3 and Figure 7 As shown, in at least one system (e.g., the first system), the stator windings (windings U1, V1, W1 of the first winding group 7) are energized to drive the rotor (rotor 6) of the motor (brake motor 4). Meanwhile, in another system (e.g., the second system), all phase disconnect switches (second phase disconnect switch 29) are turned off, the inverter circuit (second inverter circuit 22A) is also turned off, and the FS disconnect switch (second FS disconnect switch 25) is also turned off. In this state, the inverter power supply voltage monitor (second voltage monitor 64) detects the voltage based on the induced voltage generated in the other system (e.g., the second system).

[0072] If the phase disconnect switch (second phase disconnect switch 29) malfunctions (switching element 29A is ON stuck), the induced voltage can still be detected by the inverter power supply voltage monitor (second voltage monitor 64) even if all phase disconnect switches (second phase disconnect switches 29) are set to OFF. That is, the inverter power supply voltage monitor (second voltage monitor 64) detects the induced voltage generated when the rotor (rotor 6) is rotated by the parasitic diodes of the switching elements (switching element 29A) of the phase disconnect switch (second phase disconnect switch 29) that are malfunctioning (ON stuck) and the high-side switching elements of the inverter circuit (second inverter circuit 22A).

[0073] Thus, in the event of a fault (ON sticking) occurring solely in the phase disconnect switch (second phase disconnect switch 29), the induced voltage is detected by the inverter power supply voltage monitor (second voltage monitor 64). Conversely, in the event that the phase disconnect switch (second phase disconnect switch 29) does not fail (ON sticking), the inverter power supply voltage monitor (second voltage monitor 64) does not detect the induced voltage. Figure 8 An example of the time variation of the inverter power supply voltage detected by the inverter power supply voltage monitor (second voltage monitor 64) is shown.

[0074] Figure 8 The solid line 71 in the figure corresponds to the time change of the voltage detected when the phase cut-off switch (second phase cut-off switch 29) is working normally. Figure 8 The dashed line 72 corresponds to the time-varying voltage detected when the phase disconnect switch (second phase disconnect switch 29) malfunctions (ON sticking). For example... Figure 8 As shown, in the inverter power supply voltage monitor (second voltage monitor 64), when the phase disconnect switch (second phase disconnect switch 29) is normal, approximately 0V is monitored. Conversely, when the phase disconnect switch (second phase disconnect switch 29) malfunctions, the inverter power supply voltage monitor (second voltage monitor 64) monitors the specified voltage.

[0075] In this embodiment, the first and second systems of the motor control device (motor control unit 9) are divided into a drive side and a diagnostic side. On the drive side (e.g., the first system), the rotor (rotor 6) of the 6-phase motor (brake motor 4) is activated (rotated). At this time, by monitoring the voltage on the diagnostic side (e.g., the second system), a fault (ON sticking) is detected in the switching element (switching element 29A) of the phase disconnect switch (second phase disconnect switch 29).

[0076] Figure 3 and Figure 7 This indicates the ON / OFF status of each switch when a fault is detected in the second-phase disconnect switch 29 (switching element 29A). Figure 3 and Figure 7In this configuration, the first system, which is one of two systems, is designated as the "drive side (energized mode)," and the second system, which is the other system, is designated as the "diagnostic side (detection mode)." Then, a fault in the second-phase disconnect switch 29 (switching element 29A) of the second system, which is the "diagnostic side," is detected. The "drive side" is the mode (energized mode) where the stator winding (first winding group 7) is energized to drive the rotor (rotor 6). In contrast, the "diagnostic side" is the mode (detection mode) where the inverter power supply voltage monitor (second voltage monitor 64) detects the voltage based on the induced voltage generated in the stator winding (second winding group 8) due to the rotation of the rotor (rotor 6). Furthermore, although the illustration is omitted, by designating the second system as the "drive side" and the first system as the "diagnostic side," the inverter power supply voltage monitor (first voltage monitor 63) can also detect the voltage based on the induced voltage generated in the stator winding (first winding group 7) of the first system.

[0077] In the implementation method, firstly, as Figure 3 as well as Figure 7 As shown, the first system is designated as the "drive side," and the second system as the "diagnostic side." In the second system, all switching elements 29A of the second phase disconnect switch 29 are turned off, all switching elements of the second inverter circuit 22A are also turned off, and the switching element 25A of the second FS disconnect switch 25 is also turned off. Furthermore, in the first system, the rotor 6 of the brake motor 4 is rotated using the first winding group 7 (windings U1, V1, W1), while in the second system, the voltage based on the induced voltage generated in the second winding group 8 (windings U2, V2, W2) is detected using the second voltage monitor 64. This determines whether the second phase disconnect switch 29 is faulty, i.e., whether the switching element 29A is ON-stuck.

[0078] Next, although the diagram is omitted, the second system is designated as the "drive side," and the first system as the "diagnostic side." In the first system, all switching elements 19A of the first phase disconnect switch 19 are turned off, all switching elements of the first inverter circuit 12A are also turned off, and the switching element 15A of the first FS disconnect switch 15 is also turned off. Furthermore, in the second system, the rotor 6 of the brake motor 4 is rotated using the second winding group 8 (windings U2, V2, W2), while in the first system, the voltage based on the induced voltage generated in the first winding group 7 (windings U1, V1, W1) is detected using the first voltage monitor 63. This determines whether the first phase disconnect switch 19 is faulty, i.e., whether the switching element 19A is stuck in the ON position.

[0079] Furthermore, it is flexible which system to use for diagnosis first. For example, the second system can be set as the "drive side" and the first system as the "diagnosis side" to determine the presence or absence of a fault, and then the first system can be set as the "drive side" and the second system as the "diagnosis side" to determine the presence or absence of a fault. Fault diagnosis can be initiated, for example, based on instructions from the integrated control unit 35 (main ECU, brake ECU). Fault diagnosis can also be interrupted or terminated midway as needed. In addition, during diagnosis, it is confirmed that the monitored value of the inverter power supply voltage monitor (first voltage monitor 63 or second voltage monitor 64) on the diagnosis side is approximately 0. This is to confirm that there is no residual voltage. On the other hand, if residual voltage can be monitored, only the d-axis current flows, and diagnosis is performed after the residual charge is extracted. Furthermore, the diagnosis results are stored, for example, in the memory of each electronic control unit 11, 21.

[0080] Furthermore, for example, in the electric brake 2, the integrated control unit 35 (main ECU, brake ECU), which is upstream of the electronic control units 11 and 21, can control the motor drive circuits 10 and 20, which have detected faulty phase disconnect switches 19 and 29, to stop or reduce the drive of the brake motor 4. Moreover, the integrated control unit 35 (main ECU, brake ECU) operates the distribution of braking force to each wheel of the vehicle based on diagnostic results stored in the memory of each electronic control unit 11 and 21, thereby enabling control to stop or reduce the drive of the brake motor 4 by the motor drive circuits 10 and 20, which have detected faulty phase disconnect switches 19 and 29. In addition, the electronic control units 11 and 21 also have the function of storing voltages detected by voltage monitors 63 and 64.

[0081] For example, when the motor unit 3 is mounted in a vehicle, fault diagnosis can be performed as follows: Fault diagnosis is performed when the output request (output of the brake motor 4) of the brake motor 4 is below the maximum output of the motor in one system while the vehicle is in motion. Specifically, fault diagnosis is performed when the sum of the output request (output of the brake motor 4 in the first system) and the output request (output of the brake motor 4 in the second system) is below the maximum output of the motor that can be output by one system. In this case, fault diagnosis of the phase cutoff switch 19 (29) of other systems can be performed while the required force is output from the brake motor 4 through one system. Conversely, when the output request (output of the brake motor 4) of the brake motor 4 is greater than the maximum output of the motor in one system, fault diagnosis is not performed while the vehicle is in motion. The reason for this is that if fault diagnosis is performed at this time, the required force cannot be output from the brake motor 4.

[0082] Furthermore, for example, if a fault is diagnosed in the second system, specifically a fault in the switching element 29A of the second phase disconnect switch 29, motor control can be performed as follows: In this case, when the output request (output of the brake motor 4) is below the maximum output of the first system, the brake motor 4 is driven only through the first system. This reduces the frequency of use of the inverter in the second system, i.e., the second inverter 22, which is diagnosed as faulty, and lowers the probability of a double fault occurring between the switching element of the second inverter 22 and the switching element 29A of the second phase disconnect switch 29. Conversely, when the output request (output of the brake motor 4) is greater than the maximum output of the first system, the brake motor 4 is driven through both systems. This allows the required force to be output from the brake motor 4. Additionally, in the case of a fault diagnosed in the second system, a report (warning) is issued. For example, the fault information is displayed on a display device such as a monitor installed in the vehicle. Furthermore, the same motor control and reporting (warning) can be performed in the case of a fault diagnosed in the first system.

[0083] Next, the timing for fault determination (fault diagnosis) of phase disconnect switches 19 and 29 will be studied. Fault determination of phase disconnect switches 19 and 29 is not limited to the time of factory shipment, but is preferably performed during maintenance at the repair shop, during normal parking, or during driving. Hereinafter, as an embodiment, an example assuming that the electric brake 2 has been assembled or installed in the vehicle will be described.

[0084] like Figure 1 As shown, in the electric brake 2, from the viewpoint of reducing the pulling torque between the brake block 45 and the disc rotor D when not braking, a gap region (block gap) is provided between the brake block 45 and the disc rotor D. In this region, since the brake block 45 does not contact the disc rotor D, no braking force is generated. Therefore, even when the vehicle is in motion, fault determination can be performed without disrupting the vehicle's operation by checking the phase-off switches 19 and 29 in the gap region. Furthermore, fault determination can be performed in advance based on the timing when no braking force command is input from the driver or the integrated control unit 35 (main ECU, brake ECU), such as during accelerator pedal operation. Additionally, for example, it can be performed on uphill roads and / or flat straight roads where no braking force command is input on the driving path of the automatic driving system. Furthermore, for example, it can be performed in advance based on the receipt of braking status from communication with other vehicles, such as when braking is not required.

[0085] Here, when a braking force command is sent from the driver or the integrated control unit 35 (main ECU, brake ECU), it is necessary to quickly abort the fault determination and begin braking force control. In this case, the remaining four wheels that have not undergone fault determination are the electric brakes 2. Additionally, the remaining systems in the motor unit 3 that have not undergone fault determination are also included. Therefore, for each electric brake 2 of each wheel, a fault determination completion flag is managed and recorded in memory. Furthermore, a completion flag is managed for each system within the motor unit 3 and recorded in memory. This allows the remaining fault determinations to be performed at the point when the next fault determination can be performed. Furthermore, fault determination can be performed continuously and simultaneously on both the first and second systems, or it can be performed separately in each system. That is, the timing of fault determination in each system can be differentiated to shorten the fault determination time.

[0086] Furthermore, fault diagnosis can also be performed when braking force is applied via the electric brake 2. That is, fault diagnosis can be performed while the brake motor 4 is driven. However, since fault diagnosis requires requesting measurement of the induced voltage, the drive of the brake motor 4 is a single system. Therefore, for example, if the thrust value (braking force) of the braking force command is large, there is concern that the thrust required to achieve the braking force command cannot be achieved by driving the system. Therefore, it is preferable to predefine the range of the thrust value of the braking force command that allows for fault diagnosis, and if the braking force command falls outside this range, the fault diagnosis is quickly interrupted to control the system in a manner that follows the braking force command. That is, fault diagnosis can be performed when the output request of the brake motor 4 is below the maximum output of the system's motor, and not when it is above the maximum output of the system's motor. In addition, when the PKB (parking brake) is activated, the vehicle stops, and even if the command value (braking force) of the braking force command is arbitrarily set, the impact on the vehicle's movement is minimal. Therefore, in the case of fault diagnosis during braking by the electric brake 2, it is suitable to perform the fault diagnosis when the PKB is activated.

[0087] Next, the case of a four-wheeled automobile, specifically a vehicle system equipped with electric brakes 2 on each of its four wheels, allowing independent adjustment of braking force for each wheel, is investigated. Furthermore, fault determination is not limited to use in four-wheeled automobiles; it can also be used in two-wheeled, three-wheeled, and six-wheeled vehicles, as well as in trucks, passenger cars, and even other vehicles. That is, it can be used in various transport equipment and mobile robots equipped with locomotives. In any case, fault determination is preferably performed in a manner that maintains the vehicle (including transport equipment and mobile robots) in a stationary state or in a manner that does not disrupt vehicle behavior while in motion. Therefore, in this embodiment, by adjusting the braking force of each wheel, fault determination can be performed on any wheel while maintaining the braking force intended by the driver or the integrated control device 35 (main ECU, brake ECU).

[0088] That is, as mentioned above, fault determination in one wheel can be performed when the thrust is 0 or when braking is applied. However, since the brake motor 4 is driven by one system and the induced voltage is measured by another system during fault determination, there is a concern that the braking force may be insufficient relative to the braking force command. Therefore, it is considered to compensate for the insufficient thrust caused by fault determination in one wheel by increasing or decreasing the braking force of other wheels.

[0089] First, let's explain the driving process. For simplicity, we'll assume a straight, flat road without any tilting or turning. When braking commands from the driver or the automatic driving system, or braking commands based on emergency avoidance braking, are invoked, the braking force on each wheel is adjusted to satisfy these commands without disrupting vehicle behavior. Therefore, even if a fault is detected at any wheel, braking force can be applied while ensuring vehicle stability.

[0090] For example, equal braking force can be applied to either the front or rear wheels in a manner that does not generate yaw moment in the vehicle. Alternatively, braking wheels that do not generate yaw moment, such as FR and RL wheels, FL and RR wheels, can be selected to generate equal braking force in both wheels. Thus, even if the wheel being assessed for a malfunction does not generate the intended braking force, stable braking can be achieved without disrupting vehicle behavior.

[0091] When the coefficients of friction on the road surface differ among the wheels, or when the tire characteristics (Cp characteristics, etc.) are unclear, feedback control of the braking force is implemented based on the value of yaw rate sensor, etc., being 0. Alternatively, when the coefficients of friction on the road surface or the tire characteristics are known, a braking force with a yaw moment of 0 is pre-distributed. A combination of these two methods can also be used.

[0092] Next, we will explain the parking procedure. For simplicity, we will position the vehicle along the slope so that its tires do not generate lateral forces, and assume that it can drive straight without steering. In a typical parking situation with a vehicle equipped with electric brake 2, there are situations where the driving force acts on the vehicle due to crawling, or where the terrain is tilted. If braking force is not continuously applied, the vehicle may unexpectedly start moving. Therefore, during parking, based on the tilt angle obtained from the vehicle's acceleration sensor, tilt sensor, etc., we calculate the front and rear forces applied to the vehicle based on the traction force and driving force generated by the vehicle's gravity, and then calculate the total value of the braking force that balances these forces. Furthermore, we select brake wheels that do not generate yaw moments, such as FR and RL wheels, FL and RR wheels, and adjust the braking force to ensure that the braking force is equal in both wheels. Thus, even if a fault is detected in any wheel, the vehicle can remain stationary.

[0093] In this way, fault diagnosis can be performed regardless of whether the vehicle is in motion or stationary. Furthermore, the above explanation assumes that while in motion, the road is flat and level, and the vehicle is traveling straight without turning or veering. Similarly, when stationary, the vehicle is positioned along an incline to avoid generating lateral forces on the tires, and the vehicle is traveling straight without turning. However, this is not a limitation; fault diagnosis can also be performed on uneven roads, on inclines, while turning, while veering, or when lateral forces are generated while stationary. In these cases, fault diagnosis calculates the forces generated on the tires, the forces generated on the vehicle, and the torques, and calculates the balance (dynamics and statics) with the braking forces of each wheel, thereby generating braking forces for each wheel in a manner that maintains the vehicle's stationary state or does not disturb its movement. In this scenario, the forces generated by the tires, the forces generated by the vehicle, and the torques are calculated using one or more of the following: tilt sensors, acceleration sensors, yaw rate sensors, vehicle speed sensors, steering angle sensors (steering wheel angle sensors) mounted on the vehicle; vehicle position and attitude obtained from GPS; terrain information and road surface information from the 3D map used by autonomous driving; vehicle information (tread width, wheelbase, center of gravity position, vehicle mass, moment of inertia, weight distribution of each wheel, etc.); and tire characteristics (Cp characteristics, etc.).

[0094] In summary, according to the embodiment, the electric brake 2 is configured as a motor device 3 comprising multiple systems. That is, the electric brake 2 includes a motor device 3 and a braking mechanism 41. The electric brake 2 is installed on a vehicle. The electric brake 2 drives the motor (brake motor 4) to press the braking component (brake block 45) toward the braked component (disc rotor D). The motor device 3 includes a motor (brake motor 4) and a motor control unit 9. The motor control unit 9 is a motor control device with multiple systems. The motor control unit 9 includes multiple motor drive circuits (first motor drive circuit 10, second motor drive circuit 20) and multiple control units (first electronic control unit 11, second electronic control unit 21). The motor (brake motor 4) has stator windings (windings U1, V1, W1, U2, V2, W2) of multiple systems (first system, second system).

[0095] The motor drive circuits (first motor drive circuit 10 and second motor drive circuit 20) are connected between the motor (brake motor 4) and the power supply (first power supply 31 and second power supply 32), and can independently energize the motor (brake motor 4). That is, the motor drive circuits (first motor drive circuit 10 and second motor drive circuit 20) can independently energize each system (first system and second system) of the stator windings (windings U1, V1, W1, U2, V2, W2) of the motor (brake motor 4). The control unit (first electronic control unit 11 and second electronic control unit 21) controls the energizing of the motor drive circuits (first motor drive circuit 10 and second motor drive circuit 20). That is, the control unit (first electronic control unit 11 and second electronic control unit 21) controls the energizing state of the motor drive circuits (first motor drive circuit 10 and second motor drive circuit 20).

[0096] Multiple motor drive circuits (first motor drive circuit 10, second motor drive circuit 20) each have an inverter (first inverter 12, second inverter 22), a measurement unit (first voltage monitor 63, second voltage monitor 64), a motor cut-off switch (first phase cut-off switch 19, second phase cut-off switch 29), and a power cut-off switch (first FS cut-off switch 15, second FS cut-off switch 25). Specifically, the first motor drive circuit 10 has a first inverter 12 (first inverter circuit 12A), a first voltage monitor 63, a first phase cut-off switch 19 (first phase cut-off switch element 19A), and a first FS cut-off switch 15 (first FS cut-off switch element 15A). The second motor drive circuit 20 has a second inverter 22 (second inverter circuit 22A), a second voltage monitor 64, a second phase cut-off switch 29 (second phase cut-off switch element 29A), and a second FS cut-off switch 25 (second FS cut-off switch element 25A).

[0097] Inverters (first inverter 12 and second inverter 22) are positioned between the motor (brake motor 4) and the power supply (first power supply 31 and second power supply 32). Specifically, the first inverter circuit 12A of the first inverter 12 is positioned between the first winding group 7 of the brake motor 4 and the first power supply 31. The second inverter circuit 22A of the second inverter 22 is positioned between the second winding group 8 of the brake motor 4 and the second power supply 32. Measurement units (first voltage monitor 63 and second voltage monitor 64) measure the voltage of the inverters (first inverter 12 and second inverter 22). Specifically, the first voltage monitor 63 measures the voltage of the first inverter circuit 12A of the first inverter 12, and the second voltage monitor 64 measures the voltage of the second inverter circuit 22A of the second inverter 22. Alternatively, the measurement unit may be a measurement unit that measures the current of the inverter (first inverter 12, second inverter 22) (for example, a first phase current monitoring circuit 61 as a first current monitor and a second phase current monitoring circuit 62 as a second current monitor).

[0098] The motor disconnect switches (first phase disconnect switch 19, second phase disconnect switch 29) disconnect the power supply from the inverters (first inverter 12, second inverter 22) to the motor (brake motor 4). Specifically, the switching element 19A of the first phase disconnect switch 19 disconnects the power supply from the first inverter circuit 12A of the first inverter 12 to the first winding group 7 of the brake motor 4. The switching element 29A of the second phase disconnect switch 29 disconnects the power supply from the second inverter circuit 22A of the second inverter 22 to the second winding group 8 of the brake motor 4. The power disconnect switches (first FS disconnect switch 15, second FS disconnect switch 25) disconnect the power supply from the power sources (first power source 31, second power source 32) to the inverters (first inverter 12, second inverter 22). Specifically, the switching element 15A of the first FS disconnect switch 15 disconnects the power supply from the first power source 31 to the first inverter circuit 12A of the first inverter 12. The switching element 25A of the second FS disconnect switch 25 disconnects the power supply from the second power supply 32 to the second inverter circuit 22A of the second inverter 22.

[0099] Based on this, the control unit (first electronic control unit 11 and / or second electronic control unit 21) includes an anomaly determination unit that determines whether there is an anomaly (ON sticking fault of switching elements 19A and 29A) in the motor cut-off switch (first phase cut-off switch 19, second phase cut-off switch 29). When the motor drive circuit of one system (e.g., first motor drive circuit 10) cuts off the motor cut-off switch (e.g., switching element 29A of second phase cut-off switch 29) and power cut-off switch (e.g., switching element 25A of second FS cut-off switch 25) of another system, if the voltage or current is detected by the measurement unit of the other system (e.g., second voltage monitor 64), the anomaly determination unit determines that there is an anomaly in the motor cut-off switch (e.g., second phase cut-off switch 29) of the other system.

[0100] That is, such as Figure 3 and Figure 7 As shown, the control unit (first electronic control unit 11 and / or second electronic control unit 21) energizes the stator windings (windings U1, V1, W1) of at least one system (first system) to drive the rotor (rotor 6), thereby generating an induced voltage in the stator windings (e.g., windings U2, V2, W2) of other systems (second system). At this time, the control unit (first electronic control unit 11 and / or second electronic control unit 21) disconnects the switching elements of the motor disconnection switch (switching element 29A of the second phase disconnection switch 29) and the power disconnection switch (switching element 25A of the second FS disconnection switch 25) of the other system (second system). Additionally, the switching elements of the inverter (second inverter 22) of the other system (second system) are also disconnected. In this state, the fault determination unit detects the voltage or current through the measurement unit (second voltage monitor 64) of the other system (second system).

[0101] If the measurement unit (second voltage monitor 64) detects voltage or current, the anomaly determination unit determines that the motor cut-off switch (second phase cut-off switch 29) of the other system (second system) is abnormal. That is, the anomaly determination unit determines that the switching element (switching element 29A of the second phase cut-off switch 29) of the motor cut-off switch of the other system (second system) is ON and stuck. If the measurement unit (second voltage monitor 64) does not detect voltage or current, the anomaly determination unit determines that the motor cut-off switch (second phase cut-off switch 29) of the other system (second system) is not abnormal. That is, the anomaly determination unit determines that the switching element (switching element 29A of the second phase cut-off switch 29) of the motor cut-off switch of the other system (second system) is not ON and stuck. Alternatively, the anomaly determination can be performed with one system (first system) in the opposite order to the other system (second system).

[0102] In this embodiment, the motor control unit 9, which is a motor control device for multiple systems, is installed on the vehicle together with the brake motor 4. The fault determination unit makes a determination while the vehicle is in motion. In this case, the fault determination unit makes a determination while the vehicle is in motion when the output request of the brake motor 4 is below the maximum output of one system's motor. Conversely, the fault determination unit does not make a determination while the vehicle is in motion when the output request of the brake motor 4 is greater than the maximum output of one system's motor. When the fault determination unit determines that the motor cut-off switch (e.g., the second phase cut-off switch 29) of another system is faulty, the control unit (first motor drive circuit 10, second motor drive circuit 20) drives the motor drive circuit as follows: That is, when the output request of the brake motor 4 is below the maximum output of one system's motor, the control unit (first electronic control unit 11 and / or second electronic control unit 21) drives the inverter of one system (e.g., the first inverter 12). At this time, the inverters of other systems (e.g., the second inverter 22) are not driven. In contrast, when the output request of the brake motor 4 is greater than the maximum output of the motor of a system, the control unit (first electronic control unit 11 and / or second electronic control unit 21) drives the inverters (first inverter 12 and second inverter 22) of one system and other systems.

[0103] Furthermore, the control unit (first electronic control unit 11 and / or second electronic control unit 21) issues a warning if the anomaly determination unit determines that a motor cut-off switch (e.g., second phase cut-off switch 29) of another system is malfunctioning. For example, the control unit (first electronic control unit 11 and / or second electronic control unit 21) outputs a signal indicating an anomaly to the integrated control device 35. The integrated control device 35 displays the anomaly on a display device (notification device, warning device) such as a monitor installed in the vehicle. The anomaly determination unit determines an anomaly when the vehicle is parked and braking force is maintained on at least one wheel by the electric brake 2. The anomaly determination unit determines an anomaly when the vehicle is in motion in the area (gap area) where the brake pad 45, which is a braking component, does not contact the disc rotor D, which is the braked component.

[0104] Furthermore, in addition to being located in the first electronic control unit 11 and / or the second electronic control unit 21, the anomaly detection unit may also be located in other control devices (ECUs) such as the integrated control device 35 (main ECU, brake ECU). In other words, the control unit is not limited to the first electronic control unit 11, the second electronic control unit 21, the integrated control device 35, etc., but corresponds to various control devices that control the drive of the motor (brake motor 4), that is, various control devices that control the energization of the motor drive circuit (first motor drive circuit 10, second motor drive circuit 20).

[0105] As described above, according to the embodiment, the first electronic control unit 11 and / or the second electronic control unit 21 include an anomaly determination unit. Furthermore, for example, when the first motor drive circuit 10 is driven to disconnect the second phase disconnect switch 29 (switching element 29A) and the second FS disconnect switch 25 (switching element 25A), if a voltage is detected by the second voltage monitor 64, the anomaly determination unit determines that the second phase disconnect switch 29 (switching element 29A) is abnormal. Additionally, for example, when the second motor drive circuit 20 is driven to disconnect the first phase disconnect switch 19 (switching element 19A) and the first FS disconnect switch 15 (switching element 15A), if a voltage is detected by the first voltage monitor 63, the anomaly determination unit determines that the first phase disconnect switch 19 (switching element 19A) is abnormal.

[0106] Therefore, it is possible to detect a fault occurring individually in the first phase disconnect switch 19 (switching element 19A) and / or the second phase disconnect switch 29 (switching element 29A). Furthermore, while the technology in Patent Document 1 described above includes a pre-charging circuit for applying voltage, in this embodiment, such a special diagnostic circuit is not required. Therefore, in this embodiment, the circuitry can be simplified, the number of components can be reduced, and cost increases can be suppressed.

[0107] According to the embodiment, when the output request of the brake motor 4 is below the maximum output of a system's motor, the fault determination unit performs the determination while the vehicle is in motion. Therefore, even while the vehicle is in motion, fault determination can be performed while the brake motor 4 is being driven by one system, outputting the required force, and other systems are in a non-driven state. Thus, fault determination is not limited to fault determination (initial determination) when the vehicle starts (when the vehicle power is on) or fault determination (end determination) when the vehicle ends (when the vehicle power is off), but can be performed during other vehicle motion. As a result, the frequency of fault detection can be increased.

[0108] According to the implementation method, when the output request of the brake motor 4 exceeds the maximum output of a system motor, the anomaly determination unit does not perform a determination while the vehicle is in motion. Therefore, it is possible to suppress changes in the driving feel and vehicle behavior due to anomaly determinations during vehicle operation.

[0109] According to the embodiment, when the anomaly determination unit determines that the second phase cut-off switch 29 (switching element 29A) is malfunctioning, the first inverter 12 is driven but the second inverter 22 is not driven when the output request of the brake motor 4 is below the maximum output of the motor in one system (first system). This reduces the frequency of use of the second inverter 22 and lowers the probability of failure (double failure) of both the switching elements of the second inverter circuit 22A and the switching element 29A of the second phase cut-off switch 29. Therefore, the probability of dynamic braking is reduced. On the other hand, when the output request of the brake motor 4 is greater than the maximum output of the motor in one system (first system), both the first inverter 12 and the second inverter 22 are driven. This suppresses changes in driving feel and vehicle movement.

[0110] According to the embodiment, when the anomaly determination unit determines that the first phase disconnect switch 19 (switching element 19A) is malfunctioning, the second inverter 22 is driven instead of the first inverter 12 when the output request of the brake motor 4 is below the maximum output of the motor in one system (second system). This reduces the operating frequency of the first inverter 12 and lowers the probability of failure (double failure) of both the switching elements of the first inverter circuit 12A and the switching element 19A of the first phase disconnect switch 19. Therefore, the probability of dynamic braking is reduced. On the other hand, when the output request of the brake motor 4 is greater than the maximum output of the motor in one system (second system), both the second inverter 22 and the first inverter 12 are driven. This suppresses changes in driving feel and vehicle movement.

[0111] According to the embodiment, a warning is issued when the anomaly determination unit determines that there is an anomaly in the second phase disconnect switch 29 (switching element 29A) or the first phase disconnect switch 19 (switching element 19A). Therefore, based on this warning, repair or replacement of the second phase disconnect switch 29 (switching element 29A) or the first phase disconnect switch 19 (switching element 19A) can be performed. From this perspective, the probability of occurrence of a fault in both the second phase disconnect switch 29 (switching element 29A) and the second inverter circuit 22A (switching element) (double fault), or a fault in both the first phase disconnect switch 19 (switching element 19A) and the first inverter circuit 12A (switching element) (double fault), i.e., the probability of dynamic braking, can also be reduced.

[0112] According to the implementation method, while the vehicle is parked, an anomaly determination is performed while the braking force is maintained by the electric brake 2 for at least one round. Therefore, anomaly determination can be performed while the vehicle is parked, maintaining the vehicle's position. Thus, even when anomaly determination is performed while the vehicle is parked, discomfort to the driver can be minimized.

[0113] According to the implementation method, the fault detection is performed in the gap area where the brake block 45 does not contact the disc rotor D while the vehicle is in motion. Therefore, even when an anomaly is detected while the vehicle is in motion, discomfort to the driver can be suppressed. Moreover, anomaly detection is not limited to the initial detection when the vehicle starts (when the vehicle power is turned on) or the termination detection when the vehicle ends (when the vehicle power is turned off), but can also be performed during other vehicle motion. As a result, the frequency of fault detection can be increased.

[0114] Furthermore, in this embodiment, an example of a dual system (dual system) having a first electronic control unit 11 (main system) and a second electronic control unit 21 (sub-system) has been described. However, it is not limited to this; for example, it can be used in multiple systems (multiple systems) such as triple systems (three systems), quadruple systems (four systems), etc., where there are two or more dual systems (two systems). Additionally, in this embodiment, only one rotation angle sensor 30 is used, but multiple rotation angle sensors 30 can also be used. For example, a rotation angle sensor can be provided for each system. In other words, one rotation sensor can be used in one system, or a single rotation sensor can be shared in two or more systems.

[0115] In this embodiment, the example described is a brake motor 4, which is an electric brake 2 that applies braking force to the vehicle, and is driven by the first motor drive circuit 10 and the second motor drive circuit 20. However, it is not limited to this. For example, the motor driven by the first motor drive circuit and the second motor drive circuit could also be a steering motor that controls (drives) the steering actuator of the vehicle. That is, the motor driven by the first motor drive circuit and the second motor drive circuit can be any type of motor mounted on the vehicle, such as a brake motor or a steering motor (a motor that needs to ensure redundancy).

[0116] In this context, for example, it can be configured as a water pump, oil pump, or driving motor that requires redundant structure and needs to continue control in the remaining single system in the event of a single system failure. Furthermore, the motor driven by the first motor drive circuit and the second motor drive circuit is not limited to motors mounted in vehicles; it can be configured as a motor mounted in various mechanical devices other than vehicles. In other words, the motor control device of this embodiment can be widely used as a variety of motor control devices capable of continuing motor control in the remaining single system (capable of performing a failure operation) in the event of a single system failure.

[0117] In this embodiment, the vehicle controller connected to the electronic control units 11 and 21 is described as an example of an integrated control unit 35 (integrated ECU, central ECU), which determines vehicle motion control for moving the vehicle relative to a target trajectory obtained from the automatic driving control unit (automatic driving ECU). However, this is not a limitation; the vehicle controller may be, for example, a control device other than the integrated control unit 35, such as a steering control device or a suspension control device, i.e., a higher-level control device. Furthermore, the vehicle controller may also be a braking control unit (brake ECU). In other words, the vehicle controller connected to the electronic control units 11 and 21 can be any control device (ECU) mounted on the vehicle.

[0118] According to the embodiment described above, the control unit includes an anomaly determination unit that determines whether the motor cut-off switch is malfunctioning. When driving the motor drive circuit of one system and cutting off the motor cut-off switch and power cut-off switch of another system, if the measuring unit of another system detects voltage or current, it determines that the motor cut-off switch of that other system is malfunctioning. Therefore, it is possible to detect a fault in the motor cut-off switch alone. Furthermore, in the technology of Patent Document 1 described above, a pre-charging circuit for applying voltage is provided, but such a special diagnostic circuit is not required. Therefore, the circuit can be simplified, the number of components can be reduced, and cost increases can be suppressed.

[0119] According to the implementation method, when the motor's output request is below the maximum output of a system's motor, the fault determination unit performs the determination while the vehicle is in motion. Therefore, fault determination can be performed even when the required force is output from the motor through the drive of one system and other systems are not driven. Thus, fault determination is not limited to fault determination (initial determination) when the vehicle starts (when the vehicle power is on) or fault determination (end determination) when the vehicle ends (when the vehicle power is off), but can also be performed during other vehicle motion. As a result, the frequency of fault detection can be increased.

[0120] According to the implementation method, when the motor's output request exceeds the maximum output of a system's motor, the anomaly detection unit does not perform a detection while the vehicle is in motion. Therefore, it is possible to suppress changes in the driving feel and vehicle behavior caused by anomaly detection during vehicle operation.

[0121] According to the implementation method, when the anomaly determination unit determines that the motor cut-off switch of another system is malfunctioning, the inverter of one system is driven when the motor output request is below the maximum output of the motor of one system. This reduces the frequency of use of the inverters of other systems that are determined to be malfunctioning, and reduces the probability of failure (double failure) of both the inverter of that other system and the motor cut-off switch. That is, it reduces the probability of dynamic braking. On the other hand, when the motor output request is greater than the maximum output of the motor of one system, the inverters of one system and other systems are driven. This suppresses changes in operator feel and vehicle movement.

[0122] According to the implementation method, a warning is issued when the anomaly determination unit determines that the motor cut-off switch of another system is abnormal. Therefore, the motor cut-off switch of the other system can be repaired or replaced based on the warning. From this perspective, the probability of failure of both the inverter and the motor cut-off switch of the other system (double failure) can also be reduced, that is, the probability of dynamic braking occurring.

[0123] According to the implementation method, the determination is made while the vehicle is parked, with braking force maintained by the electric brake for at least one round. Therefore, the determination can be made while the vehicle is parked, maintaining the vehicle's position. Thus, even when the determination is made while the vehicle is parked, discomfort to the driver can be minimized.

[0124] According to the implementation method, the fault determination is performed in the area where the braking component and the braked component do not contact while the vehicle is in motion. Therefore, even when the determination is performed while the vehicle is in motion, discomfort to the driver can be suppressed. Moreover, fault determination is not limited to fault determination (initial determination) when the vehicle starts (when the vehicle power is turned on) or fault determination (end determination) when the vehicle ends (when the vehicle power is turned off), but can also be performed during other times of vehicle operation. As a result, the frequency of fault detection can be increased.

[0125] Furthermore, the present invention is not limited to the embodiments described above, and includes various modifications. For example, the embodiments described above are detailed for ease of understanding and explanation of the present invention, and are not limited to having all the structures described. In addition, a part of the structure of a certain embodiment can be replaced with the structure of another embodiment, and it is also possible to add the structure of another embodiment to the structure of a certain embodiment. Furthermore, for a part of the structure of each embodiment, other structures can be added, deleted, or replaced.

[0126] This application claims priority based on Japanese Patent Application No. 2023-192054, filed on November 10, 2023. The entire disclosure of Japanese Patent Application No. 2023-192054, filed on November 10, 2023, including the description, claims, drawings and abstract, is incorporated herein by reference in its entirety.

[0127] Explanation of reference numerals in the attached figures

[0128] 1 Braking system; 2 Electric brake; 3 Motor assembly; 4 Brake motor; 6 Rotor (rotating component); 7 First winding group (stator winding); 8 Second winding group (stator winding); 10 First motor drive circuit (motor drive circuit); 11 First electronic control unit (control unit); 12 First inverter (inverter); 12A First inverter circuit (3-phase bridge circuit); 15 First FS disconnect switch (power disconnect switch); 15A Switching element; 19 First phase disconnect switch (motor disconnect switch); 19A Switching element; 20 Second motor Drive circuit (motor drive circuit); 21 Second electronic control unit (control unit); 22 Second inverter (inverter); 22A Second inverter circuit (3-phase bridge circuit); 25 Second FS disconnect switch (power disconnect switch); 25A Switching element; 29 Second phase disconnect switch (motor disconnect switch); 29A Switching element; 31 First power supply (power supply); 32 Second power supply (power supply); 45 Brake block (braking component); 63 First voltage monitor (measuring unit); 64 Second voltage monitor (measuring unit); D-disc rotor (braked component).

Claims

1. A motor control device, comprising: Multiple motor drive circuits are connected between a motor with multiple stator winding systems and a power source, enabling independent energization of each system of the motor's stator windings. as well as Multiple control units control the power supply to the motor drive circuit. Each of the plurality of motor drive circuits has: An inverter is disposed between the motor and the power supply; The measurement unit measures the voltage or current of the inverter; A motor shut-off switch cuts off the power supply from the inverter to the motor; as well as A power cut-off switch cuts off the power supply from the power source to the inverter. The control unit has an anomaly determination unit. When the motor drive circuit of one system is driven and the motor cut-off switch and the power cut-off switch of another system are turned off, the anomaly determination unit determines that the motor cut-off switch of the other system is abnormal when the measuring unit of the other system detects voltage or current.

2. The motor control device according to claim 1, wherein, The motor control device is installed in the vehicle. When the output request of the motor is below the maximum output of a system's motor, the fault determination unit determines whether there is a fault in the motor cut-off switch of other systems during the operation of the vehicle.

3. The motor control device according to claim 1, wherein, The motor control device is installed in the vehicle. If the output request of the motor is greater than the maximum output of a system's motor, the anomaly determination unit does not determine whether there is an anomaly in the motor cut-off switch of other systems while the vehicle is in motion.

4. The motor control device according to claim 1, wherein, When the anomaly determination unit determines that the motor cut-off switch of another system is abnormal, the control unit drives the inverter of one system when the output request of the motor is below the maximum output of the motor of one system, and drives the inverters of one system and other systems when the output request of the motor is greater than the maximum output of the motor of one system.

5. The motor control device according to claim 1, wherein, If the anomaly determination unit determines that the motor cut-off switch of another system is malfunctioning, the control unit issues a warning.

6. An electric braking device comprising: a motor having a stator winding having multiple systems; and a motor control device, the electric braking device being disposed in a vehicle and driving the motor to press a braking component toward a braked component. The motor control device includes: Multiple motor drive circuits, connected between the motor and the power supply, are capable of independently energizing each system of the motor's stator windings; and Multiple control units control the power supply to the motor drive circuit. Each of the plurality of motor drive circuits has: An inverter is disposed between the motor and the power supply; The measurement unit measures the voltage or current of the inverter; A motor shut-off switch cuts off the power supply from the inverter to the motor; as well as A power cut-off switch cuts off the power supply from the power source to the inverter. The control unit has an anomaly determination unit. When the motor drive circuit of one system is driven and the motor cut-off switch and the power cut-off switch of another system are turned off, the anomaly determination unit determines that the motor cut-off switch of the other system is abnormal when the measuring unit of the other system detects voltage or current.

7. The electric braking device according to claim 6, wherein, The anomaly determination unit determines whether there is an anomaly in the motor cut-off switch of other systems while the vehicle is parked and the electric braking device maintains braking force for at least one wheel.

8. The electric braking device according to claim 6, wherein, The anomaly determination unit determines, during the vehicle's operation, in the area where the braking component and the braked component are not in contact, whether or not there is an anomaly in the motor cut-off switch of another system.

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