WO2019049731A1

WO2019049731A1 - Control device for power steering device

Info

Publication number: WO2019049731A1
Application number: PCT/JP2018/031768
Authority: WO
Inventors: 健太上阪; 光昭中田
Original assignee: 日立オートモティブシステムズ株式会社
Priority date: 2017-09-11
Filing date: 2018-08-28
Publication date: 2019-03-14
Also published as: JPWO2019049731A1

Abstract

Provided is a control device for a power steering device, with which a diagnostic range during operation of a vehicle can be expanded and a breakdown can be detected and notified early. The control device for the power steering device has a redundant configuration comprising first and second system drive units that each drive an assist electric motor. Each drive unit comprises: a diagnosis functional unit that diagnoses a breakdown; and a mode switching functional unit that, during vehicle operation in which the necessary assist force output is low, uses one of the system drive units to output assist force and causes the other system drive unit to transition to a breakdown diagnosis mode so as to perform a diagnosis of a drive circuit or a power supply circuit.

Description

Control device for power steering device

The present invention relates to a control device of a power steering device configured to be redundant.

With EPS (Electric Power Steering) having a redundant system, failure diagnosis of some functions and circuits can not be performed during vehicle operation because assist power output can not be performed. Therefore, failure diagnosis is performed only before the output of the assist force at the start of driving. Therefore, while the vehicle is in operation, even if a failure occurs in the function or circuit, it is not possible to find out the diagnosis at the next activation.
Therefore, for example, in the electric power steering apparatus of Patent Document 1, the assist motor is provided with a prediction unit for predicting a period in which the drive current does not flow, and when it is estimated that the period does not flow the drive current in the motor Diagnosis of the circuit related to vehicle operation during vehicle operation.

JP, 2016-113024, A

By the way, in recent years, with the spread of EPS, further improvement of the product power has been desired, and it is desirable that the diagnostic range at the time of vehicle traveling be as wide as possible, and include the earlier failure detection and failure notification function. There is a demand.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a control apparatus of a power steering apparatus capable of expanding a diagnosis range during driving of a vehicle and capable of early detection and notification of a failure. It is to do.

The control device of the power steering apparatus according to the present invention is, in one aspect thereof, a system of a redundant configuration provided with a plurality of drive units for driving the assist motors, respectively, during driving of the vehicle with a small required assist force output. In the period, the drive power output is carried by a part of drive units of a plurality of systems, and the mode switching function unit is provided to make the drive units of the remaining systems transition to the diagnostic mode and diagnose the drive circuit or the power supply circuit. .

According to the present invention, in a control device of a power steering apparatus having a redundant configuration provided with a plurality of drive units, when the drive units of a part of the systems are in the assist mode, drive circuits or power supplies of drive units of the remaining systems. The circuit diagnosis can be performed, and the opportunity for diagnosis of the drive circuit and the power supply circuit can be increased. Therefore, the diagnostic range during driving of the vehicle can be expanded, early detection and notification of a failure can be performed, and safety can be improved.

FIG. 1 is a perspective view showing a schematic configuration by extracting main parts related to a power steering apparatus according to an embodiment of the present invention. It is a block diagram showing an example of composition of ECU for EPS control in a control device of a power steering device concerning an embodiment of the present invention. It is a functional block diagram of a control device of a power steering device concerning a 1st embodiment of the present invention. It is a block diagram which shows the structural example of the 1st microcontroller in FIG. 3A. It is a block diagram which shows the structural example of the 2nd microcontroller in FIG. 3A. It is a flowchart which shows roughly operation | movement in the control apparatus shown to FIG. 3A, FIG. 3B and FIG. 3C. It is a flowchart which shows an example of the failure diagnosis mode switch determination process in FIG. It is a flowchart which shows an example of the failure diagnosis mode interruption request | requirement determination processing in FIG. It is a flowchart which shows an example of the failure diagnosis mode transition process in FIG. It is a flowchart which shows an example of the assist force output mode reset process in FIG. It is a flowchart which shows an example of the failure diagnostic process in FIG. It is a functional block diagram of a control device of a power steering device concerning a 2nd embodiment of the present invention. It is a block diagram which shows the structural example of the 1st microcontroller in FIG. 10A. It is a block diagram which shows the structural example of the 2nd microcontroller in FIG. 10A. It is a functional block diagram of a control device of a power steering device concerning a 3rd embodiment of the present invention. It is a functional block diagram of a control device of a power steering device concerning a 4th embodiment of the present invention. It is a block diagram which shows the structural example of the 1st microcontroller in FIG. 12A. It is a block diagram which shows the structural example of the 2nd microcontroller in FIG. 12A. It is a functional block diagram of a control device of a power steering device concerning a 5th embodiment of the present invention. It is a block diagram which shows the structural example of the 1st microcontroller in FIG. 13A. It is a block diagram which shows the structural example of the 2nd microcontroller in FIG. 13A.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
First Embodiment
FIG. 1 shows a schematic configuration by extracting main parts related to a power steering apparatus according to an embodiment of the present invention. The power steering apparatus 10 includes a rack housing 11, a motor housing 12, an electric motor (three-phase brushless motor) 13 having two winding sets, a reduction gear 14, a pinion 15,

dust boots

16, 16,

tie rods

17, 17 and A steering mechanism 18 and the like are provided. The rack housing 11 houses a pinion shaft and a rack bar (not shown) and a part of the steering shaft 19. Further, the motor housing 12 accommodates the electric motor 13 and the EPS control ECU 3. Then, the rotation of the electric motor 13 is decelerated by the reduction gear 14 and transmitted to the steering mechanism 18 to assist the steering force by the driver of the vehicle and apply it to the steered wheels.

The steering mechanism 18 has a steering shaft 19, a pinion shaft and a torsion bar. The steering shaft 19 rotates integrally with the steering wheel. On the steering shaft 20, a steering torque sensor 21 and a steering angle sensor 22 as a steering sensor for detecting the steering state of the steering mechanism 18 are attached. The steering torque sensor 21 and the steering angle sensor 22 are respectively provided in pairs. The steering torque sensor 21 detects a steering torque (torsion bar torque) generated in the steering mechanism 18 based on the amount of torsion of the torsion bar. The steering angle sensor 22 detects a steering angle at the time of steering operation.

The pinion shaft is connected to the steering shaft 19 via a torsion bar. The

dust boots

16 and 16 are formed in a bellows shape using rubber or the like. Outer ends in the vehicle width direction of the

dust boots

16, 16 are fixed to inner ends in the vehicle width direction of the

tie rods

17, 17. The ends of the pair of

tie rods

17, 17 are connected to both ends of the rack bar.

FIG. 2 is a block diagram showing a configuration example of the EPS control ECU 3 in FIG. The EPS control ECU 3 has a logic circuit unit 3a mounted on a printed circuit board and a power circuit unit 3b mounted on a metal printed circuit board. The logic circuit unit 3 a operates with an internal power supply voltage generated by a power supply IC or the like, and the power circuit unit 3 b operates with an external power supply voltage supplied from the battery 31. And with metal printed circuit boards, measures against heat radiation of power devices with large calorific value and measures against reliability of electronic parts by heat are taken.

The logic circuit unit 3a and the power circuit unit 3b have a redundant configuration including first and second drive units EPP1 and EPP2 having a dashed dotted line DL as a boundary. The logic circuit unit 3a of the drive unit EPP1 of the first system is composed of a first microcontroller (in this example, dual core CPU) 32, a predriver 33, a CPU monitor 34, a virtual motor position detector (inductance detector) 35, etc. Be done. The power circuit unit 3 b includes a first inverter 40 and a first current detection unit 42 of a 3-shunt system. The current detection unit 42 is used as a motor phase current sensor and a primary current sensor.

Similarly, the logic circuit unit 3a of the drive unit EPP2 of the second system includes a second microcontroller (dual core CPU in this example) 36, a predriver 37, a CPU monitor 38 and a virtual motor position detector (inductance detector) 39. And so on. The power circuit unit 3 b includes a second inverter 41 and a three-shunt second current detection unit 43. The current detection unit 43 is used as a motor phase current sensor and a primary current sensor.

The first and

second microcontrollers

32 and 36 respectively perform EPS assist control calculation, motor current control, functional component abnormality detection, and transition processing to a safe state. Power supply voltages are applied to the first and

second microcontrollers

32 and 36 from the internal operation power supplies 48 and 49, respectively. The CPU monitors 34 and 38 detect an abnormality that has occurred in the

microcontrollers

32 and 36, and have a function of shutting off the power supply to the

microcontrollers

32 and 36 when it is determined that they are abnormal. The

predrivers

33 and 37 drive the drive elements in the

inverters

40 and 41 based on the commands from the

microcontrollers

32 and 36, respectively. The

inverters

40 and 41 are composed of a plurality of drive elements for supplying current to the electric motor 13, and operate based on commands from the

predrivers

33 and 37. In accordance with the drive current from the

inverters

40 and 41, the electric motor 13 having the two winding sets is driven to generate motor torque.

The

current detection units

42 and 43 have a function of monitoring whether the current value required by the motor control is as intended to output the required torque of the electric motor 13 obtained from the assist control and the primary current (from the battery 31 It has a function of monitoring the current (captured current) to the drive units EPP1 and EPP2.
A power supply voltage is applied to the first steering sensor 23a (the steering torque sensor 21a and the steering angle sensor 22a) of the drive unit EPP1 from the internal operation power supply 45 of the logic circuit unit 3a, and the detection output is the first and second microcontrollers 32. , 36, respectively. A power supply voltage is applied to the second steering sensor 23b (the steering torque sensor 21b and the steering angle sensor 22b) of the drive unit EPP2 from the internal operation power supply 47 of the logic circuit unit 3a, and the detection output is the second and first micro The signals are supplied to the

controllers

36 and 32, respectively.

Here, dual sensors respectively corresponding to the dual core CPU can be used as the steering torque sensor 21a and the steering angle sensor 22a, and the steering torque sensor 21b and the steering angle sensor 22b. The first and

second microcontrollers

32 and 36 perform inter-microcomputer communication (inter-CPU communication) to transmit and receive a status signal and a sensor signal.
In the electric motor 13, motor rotation angle sensors (dual motor position sensors) 50a and 50b are mounted on a printed circuit board. Power supply voltages are applied to the motor

rotational angle sensors

50a and 50b from internal operation power supplies 51 and 52 provided in the logic circuit unit 3a, and detection outputs are supplied to the first and

second microcontrollers

32 and 36, respectively. .

The first microcontroller 32 is based on the three-phase current detected by the current detection unit 42, the rotational position of the rotor detected by the virtual motor position detector 35, and the motor rotational angle detected by the motor

rotational angle sensors

50a and 50b. , Generates a pulse signal for performing PWM (Pulse Width Modulation) control. The pulse signal output from the first microcontroller 32 is supplied to the predriver 33. Also, the second microcontroller 36 is based on the phase current detected by the current detection unit 43, the rotational position of the rotor detected by the virtual motor position detector 39, and the motor rotational angle detected by the motor

rotational angle sensors

50a and 50b. And generates a pulse signal for performing PWM control. The pulse signal output from the second microcontroller 36 is supplied to the predriver 37.

The operation of the first microcontroller 32 is verified by the CPU monitor 34, and the operation of the second microcontroller 36 is verified by the CPU monitor 38. The CPU monitors 34 and 38 are configured by timers called, for example, watchdogs, and constantly monitor whether the first and

second microcontrollers

32 and 36 are normal or not.

The pulse signals (PWM signals) output from the

predrivers

33 and 37 are respectively supplied to the

inverters

40 and 41, and the electric motor 13 is driven according to the current from the

inverters

40 and 41. Three-phase currents at the time of driving the electric motor 13 are detected by the

current detection units

42 and 43, respectively, and detection signals are supplied to the first and

second microcontrollers

32 and 36 to perform feedback control. The first and

second microcontrollers

32, 36 calculate the total amount of current from the battery 31 based on the three-phase current. Further, the rotational position of the rotor is detected by the virtual

motor position detectors

35 and 39 based on the neutral point voltage of the stator coil, and detection signals are supplied to the first and

second microcontrollers

32 and 36. The detection signals of the virtual

motor position detectors

35 and 39 are used for verification of detection outputs of the

current detection units

42 and 43 and the motor

rotation angle sensors

50a and 50b and for backup at the time of sensor failure.

FIG. 3A is a functional block diagram of a control device of a power steering apparatus according to a first embodiment of the present invention, showing in detail an example of functional configuration of first and second drive units EPP1 and EPP2 in FIG. There is. 3B and 3C respectively show configuration examples of the first and second microcontrollers in FIG. 3A. The drive unit EPP1 of the first system includes a first sensor 54, a first microcontroller (first microprocessor) 32, a predriver 33, an inverter 40, a motor relay 44, a power relay (first power circuit) 29, and the electric motor 13 , And the like. The pre-driver 33, the inverter 40 and the motor relay 44 function as a first drive circuit DR1 that drives the winding set 13a of the electric motor 13.

Furthermore, the drive unit EPP2 of the second system includes a second sensor 55, a second microcontroller (second microprocessor) 36, a predriver 37, an inverter 41, a motor relay 46, a power supply relay (second power supply circuit) 30, and an electric motor. It includes a winding set 13b of the motor 13 and the like. The predriver 37, the inverter 41, and the motor relay 46 function as a second drive circuit DR2 that drives the winding set 13b of the electric motor 13.

The first sensor 54 detects a state quantity indicating the driving state of the vehicle, and the steering torque sensor 21 (21a, 21b), the steering angle sensor 22 (22a, 22b), and the motor rotation angle sensor 50 (50a, 50a, A power supply voltage monitor 81 and a temperature sensor 82 are included in addition to the motor phase current sensor and primary current sensor (current detection unit) 50b). Similarly, the second sensor 55 detects a state quantity indicating the driving state of the vehicle, and the steering torque sensor 21 (21a, 21b), the steering angle sensor 22 (22a, 22b), and the motor rotation angle sensor 50 ( In addition to the motor phase current sensor / primary current sensor (current detection unit) 43, a power supply voltage monitor 83 is included.

The first microcontroller 32 generates a pulse signal for PWM control of the winding set 13 a of the electric motor 13 based on the output signal of the first sensor 54. As shown in FIG. 3B, the first microcontroller 32 has an input signal processing unit 61, a CAN communication unit (first transceiver and first controller) 62, an assist control / external command control unit 63, an assist limiting unit 64, and a motor. The control unit 65, a diagnosis function unit (first diagnosis unit) 66, a mode switching function unit (first mode switching control unit) 67, an inter-microcomputer communication unit 68, a non-volatile memory 69, and the like are provided. The assist control / external command control unit 63, the assist limiting unit 64, and the motor control unit 65 calculate a first motor command signal for driving and controlling the electric motor 13 based on a signal related to the driving state of the vehicle, and outputs the first drive circuit DR1. It works as a first motor command signal calculation unit to output. The non-volatile memory 69 functions as a first diagnostic status storage unit that stores the diagnostic status in the diagnostic function unit 66.

Similarly, the second microcontroller 36 generates a pulse signal for PWM control of the winding set 13 b of the electric motor 13 based on the output signal of the second sensor 55. As shown in FIG. 3C, the second microcontroller 36 has an input signal processing unit 71, a CAN communication unit (second transceiver and second controller) 72, an assist control / external command control unit 73, an assist limiting unit 74, and a motor. The control unit 75, a diagnostic function unit (second diagnostic unit) 76, a mode switching function unit (second mode switching control unit) 77, an inter-microcomputer communication unit 78, a non-volatile memory 79, and the like are provided. The assist control / external command control unit 73, the assist limiting unit 74, and the motor control unit 75 calculate a second motor command signal for controlling the driving of the electric motor 13 based on a signal related to the driving state of the vehicle, and send it to the second drive circuit DR2. It works as a second motor command signal calculation unit to output. The non-volatile memory 79 serves as a first diagnostic status storage unit that stores the diagnostic status in the diagnostic function unit 76.
Each CAN

communication unit

62, 72 is connected to another ECU or a vehicle-mounted device via a CAN bus (communication network) 53.

The first and

second microcontrollers

32 and 36 mutually monitor each other by inter-microcomputer communication. Further,

diagnostic function units

66 and 76 provided in these

microcontrollers

32 and 36 perform abnormality detection in the own system and abnormality detection in the other system through communication between microcomputers. Furthermore, each of the

assist limiting units

64 and 74 reduces the motor torque command to a preset torque (upper limit output) with respect to the calculation result of the assist control when the EPS control ECU 3 is overheated or the like. Protect your own system.

An output signal of each sensor in the first sensor 54 is input to the input signal processing unit 61, for example, A / D converted and converted into a digital signal. An output signal of the input signal processing unit 61 is supplied to the assist control / external command control unit 63. In the assist control / external command control unit 63, calculation of a first control amount for driving and controlling the electric motor 13 is performed based on the output signal of the first sensor 54. The first control amount includes the assist amount of the driver's steering force and, for example, the amount of steering force output by an external command regardless of the driver's steering operation in the automatic parking system. A signal output from the assist control / external command control unit 63 is supplied to the motor control unit 65 via the assist limiting unit 64. The motor control unit 65 drives and controls the winding set 13 a of the electric motor 13 via the predriver 33, the inverter 40 and the motor relay 44 based on the first control amount.

An output signal of the input signal processing unit 61 and an output signal of the CAN communication unit 62 are supplied to the diagnosis function unit 66, and presence or absence of abnormality of the output signal of the predriver 33, the inverter 40, the winding set 13a or the first sensor 54 To judge. The output signal of the diagnosis function unit 66 is supplied to the assist limiting unit 64 and the mode switching function unit 67, so that the assist of the steering force by the electric motor 13 is limited and switching to the failure diagnosis mode is executed. The mode switching function unit 67 monitors the driving condition of the vehicle, and outputs a small amount of assist force while driving the vehicle, and when it is determined that no assist force by all the systems is required, the other system (drive unit EPP2 Request that the own system (drive unit EPP1) make a transition to the failure diagnosis mode. Then, when the transition to the failure diagnosis mode is determined, the assist function of the own system is distributed to another system, and then the diagnosis function unit 66 performs the failure diagnosis. The diagnosis result is recorded in the non-volatile memory 69. If it turns out to be normal after the diagnosis, the system returns to the assist power output mode, and if a failure is found out during the diagnosis, the abnormality is notified to other systems and other systems immediately.
When the diagnostic function unit 66 determines that the output signal of the predriver 33, the inverter 40, the motor relay 44, the winding set 13a or the first sensor 54 is abnormal, the mode switching function unit 67 performs assist control and external command. The calculation stop instruction is output to the control unit 63, the assist limiting unit 64, and the motor control unit 65 to stop the calculation.

In addition, the output signal of each sensor in the second sensor 55 is input to the input signal processing unit 71, for example, A / D converted and converted into a digital signal. An output signal of the input signal processing unit 71 is supplied to the assist control / external command control unit 73. The assist control / external command control unit 73 performs calculation of a second control amount for driving and controlling the winding set 13 a of the electric motor 13 based on the output signal of the second sensor 55. The second control amount includes the assist amount of the driver's steering force and, for example, the amount of steering force output by the external command regardless of the driver's steering operation in the automatic parking system. A signal output from the assist control / external command control unit 73 is supplied to the motor control unit 75 via the assist limiting unit 74. The motor control unit 75 drives and controls the winding set 13b of the electric motor 13 through the predriver 37, the inverter 41, and the motor relay 46 based on the second control amount.

The diagnostic function unit 76 is supplied with the output signal of the input signal processing unit 71 and the output signal of the CAN communication unit 72, and there is an abnormality in the output signal of the predriver 37, the inverter 41, the winding set 13b or the second sensor 55 To judge. The output signal of the diagnosis function unit 76 is supplied to the assist limiting unit 74 and the mode switching function unit 77, so that the assist of the steering force by the electric motor 13 is limited and switching to the failure diagnosis mode is executed. The mode switching function unit 77 monitors the driving condition of the vehicle, and when it is determined that the required assist force output while driving the vehicle is small and the assist force by all the systems is not necessary, the other system (drive unit EPP1 Request that the own system (drive unit EPP2) make a transition to the failure diagnosis mode. Then, when the transition to the failure diagnosis mode is determined, the assist function of the own system is distributed to the other system, and then the diagnosis function unit 76 performs the failure diagnosis. The diagnosis result is recorded in the non-volatile memory 79. If it turns out to be normal after the diagnosis, the system returns to the assist power output mode, and if a failure is found out during the diagnosis, the abnormality is notified to other systems and other systems immediately.
When the diagnostic function unit 76 determines that the output signal of the predriver 37, the inverter 41, the motor relay 46, the winding set 13b or the second sensor 55 is abnormal, the mode switching function unit 77 performs assist control and external command. The calculation stop instruction is output to the control unit 73, the assist limiting unit 74, and the motor control unit 75 to stop the calculation.

The inter-microcomputer communication units (inter-CPU communication units) 68 and 78 perform transmission and reception of signals performed between the first microcontroller 32 and the second microcontroller 36. The inter-microcomputer communication unit 68 exchanges data with the diagnostic function unit 66 and the mode switching function unit 67, and communicates with another ECU or vehicle-mounted device via the CAN communication unit 62 and the CAN bus 53. The inter-microcomputer communication unit 78 exchanges data with the diagnostic function unit 76 and the mode switching function unit 77, and communicates with another ECU or vehicle-mounted device via the CAN communication unit 72 and the CAN bus 53. .

The mode switching function unit 67 receives a mode switching command from the microcontroller 36 via the

inter-microcomputer communication units

78 and 68, and transmits mode switching completion information to the microcontroller 36 via the

inter-microcomputer communication units

68 and 78. The mode switching function unit 77 also receives a mode switching command from the microcontroller 32 via the

inter-microcomputer communication unit

68, 78, and sends mode switching completion information to the microcontroller 32 via the

inter-microcomputer communication unit

78, 68. Send.

Next, in the configuration as described above, the control operation will be described with reference to the flowcharts of FIGS. 4 to 9. FIG. 4 is a flow chart schematically showing the operation of the control device shown in FIGS. 3A, 3B and 3C. Steps S2 to S5, S7 and S10 to S14 show the operation of mode

switching function units

67 and 77, step S8 shows the operations of

diagnostic function units

66 and 76, and steps S9 and S15 show the operations of mode

switching function units

67 and 77, respectively. ing.

Here, it is assumed that the steering assist force is output in the driving state of the vehicle (step S1). First, based on the state of the mode switching function unit, it is determined whether "other system is in failure diagnosis mode" (step S2). That is, the mode switching function unit 67 determines whether the diagnostic function unit 76 of the other system is in the failure diagnosis mode based on its own state. Further, the mode switching function unit 77 determines whether the diagnostic function unit 66 of the other system is in the failure diagnosis mode based on its own state.
If it is determined in step S2 that the failure diagnosis mode is not in effect, the diagnosis function unit of another system is accessed similarly via the

inter-microcomputer communication unit

68, 78, and a failure diagnosis mode transition notification is sent from the diagnosis function unit of another system. It is determined whether or not it has been received (step S3). If the other system is not in the failure diagnosis mode and no failure diagnosis mode transition notification is received from the other system, it is determined whether or not the own system can be switched to the failure diagnosis mode (fault diagnosis mode switching Determination) is performed (step S4).

The failure diagnosis mode switching determination determines whether or not to transition to the failure diagnosis mode based on, for example, the vehicle speed, the torque value, the steering angle, and the like. The vehicle speed is input to the

diagnostic function units

66 and 76 by CAN communication via the CAN bus 53 and the CAN communication unit 62 or the CAN bus 53 and the CAN communication unit 72, and acquired by the mode

switching function units

67 and 77. The torque value and the steering angle are acquired from the steering torque sensor 21 and the steering angle sensor 22 by the mode switching function unit 67 via the input signal processing unit 61 and the diagnostic function unit 66. Alternatively, it is acquired by the mode switching function unit 77 from the steering torque sensor 21 and the steering angle sensor 22 via the input signal processing unit 71 and the diagnostic function unit 76.

Subsequently, it is determined whether "fault diagnosis mode switching is possible" (step S5), and if it is determined that switching to the fault diagnosis mode is impossible, it is determined whether or not the assist force output ends (step S6). If it is determined in step S6 that the output of assist force is ended, the assist is ended, and if it is determined that the end is not ended, the process returns to step S1 and the output of assist force is continued.
On the other hand, if it is determined in step S5 that switching to the failure diagnosis mode is possible, the mode

switching function unit

67 or 77 stops its own assist and switches to the failure diagnosis mode (step S7), and executes failure diagnosis (step S8). ) And then return to the assist force output mode (step S9). Next, it is determined whether or not the assist force output is ended (step S6), and when it is determined that the assist force output is ended, the assist is ended, and when it is judged that it is not ended, the process returns to step S1 to output the assist force continue.

If it is determined in step S3 that the failure diagnosis mode transition notification has been received, the output of its own assist force is increased (step S10), and it is determined whether or not the assist force output is ended (step S6). If it is determined that the output is completed, the assist is ended, and if it is determined that the output is not ended, the process returns to step S1 to continue the output of the assist force.
If it is determined in step S2 that the other system is in the failure diagnosis mode, it is determined whether the assist output mode return notification has been received (step S11). If not received, the failure diagnosis mode is in progress. Therefore, failure diagnosis mode interruption request determination is performed (step S12). In the next step S13, it is determined whether or not there is a "failure diagnosis mode interruption request", and if there is no request, the process proceeds to step S6 and it is determined whether or not the assist force output is ended. If it is determined in step S6 that the output of assist force is ended, the assist is ended, and if it is determined that the end is not ended, the process returns to step S1 and the output of assist force is continued.

If it is determined in step S13 that there is a "fault diagnosis mode interruption request", an interruption request is transmitted to the "in failure diagnosis mode" system (step S14), and the process proceeds to step S6 and the assist force output ends It is determined whether or not the output of assist force is determined to end, and the assist is ended. If it is determined that the end is not determined, the process returns to step S1 to continue the output of assist force.
If it is determined in step S11 that the assist force output mode return notification has been received, the other system returns from the failure diagnosis mode. For this reason, since it is necessary to increase or decrease the assist force also in the system which is not in the failure diagnosis mode, the process proceeds to step S15 to execute the assist force output mode return. Subsequently, the process proceeds to step S6, and it is determined whether or not the assist force output is ended. If it is determined that the assist force output is ended, the assist is ended. If it is determined that it is not ended, the process returns to step S1. To continue.

<Fault diagnosis mode switching determination processing>
FIG. 5 is a flow chart showing an example of the failure diagnosis mode switching determination process of step S4 in FIG. First, it is determined whether the vehicle speed is the first predetermined speed or more (step S21). If the vehicle speed is the first predetermined speed or more, "fault diagnosis mode switchable" is returned (the second diagnosis mode is selected) and the process returns (return Step S27). Here, the first predetermined speed is set, for example, on the assumption that the vehicle is traveling at high speed.

If it is determined in step S21 that the vehicle speed is not the first predetermined speed or more, it is determined whether the vehicle speed is the second predetermined speed or less (step S22). If it is higher than the second predetermined speed, "fault diagnosis mode switchable" is returned and the process returns (step S27). Here, the second predetermined speed is set to a low speed on the assumption that, for example, a vehicle is parked, a temporary stop at an intersection, an idling stop, or the like.
If it is determined in step S22 that the speed is not lower than the second predetermined speed, it is determined whether the steering angle or torque is lower than a predetermined value (step S23). If lower than the predetermined value, "fault diagnosis mode switchable" is returned. And return (step S27). Here, as the predetermined value, for example, the steering angle or the torque is set on the assumption that the necessity for applying a large steering force is low, such as when traveling at high speed.

If it is determined in step S23 that the vehicle speed is not less than the predetermined value, it is determined whether mode switching is possible according to the vehicle operating condition received from another system (step S24). Is returned and returned (step S27). In step S24, it is determined from the signals of other related devices, such as an engine rotation number signal, a transmission position signal, a brake pedal stroke signal, a yaw rate sensor and a vehicle speed signal, that the need for applying a large steering force is low. Do.
If it is determined in step S24 that mode switching is not possible, it is determined whether 100% assist output is possible outside the own system (step S25), and if assist output is available, "fault diagnosis mode switchable" is selected. It returns and returns (step S27). If it is determined that 100% assist output is not possible except in the own system, "failure diagnosis mode switching prohibition" is returned and the process returns (step S26). In step S25, if 100% assist output is possible in another system, it is possible to switch to the failure diagnosis mode, so this is determined.

<Fault diagnosis mode interruption request determination processing>
FIG. 6 is a flowchart showing an example of the failure diagnosis mode interruption request determination process of step S12 in FIG. In the failure diagnosis mode interruption request determination process, it is determined by the

diagnosis function units

66 and 76 whether or not the system of “in assist output mode” is in normal operation (step S31), and if in normal operation It is judged by the assist control and external

command control unit

63, 73 whether or not the system can be output only by the system of the assist force output mode (step S32). If it is determined in step S31 that normal operation is not in progress, and if it is determined in step S32 that the necessary assist force can not be obtained only by the system of "assist power output mode", "failure diagnosis mode interruption request" Is returned and returned (step S33).
On the other hand, when it is determined in step S32 that the necessary assist force can be obtained only by the system of the "assist force output mode", the "failure diagnosis mode continuation request" is returned and returned (step S34).

<Fault diagnosis mode transition process>
FIG. 7 is a flow chart showing an example of the failure diagnosis mode transition process of steps S7 and S10 in FIG. In the fault diagnosis mode transition process, when the own system enters the fault diagnosis mode, an operation to gradually transfer and reduce the assist to another system is performed, and when the other system enters the fault diagnosis mode, the assist of the own system is gradually Perform an action to increase it.
First, the mode

switching function units

67 and 77 determine whether or not the own system is a system for transition to the fault diagnosis mode (step S41), and if it is a system for transition to the fault diagnosis mode, a fault diagnosis mode transition notification is transmitted Step S42). Next, the assist control / external

command control unit

63, 73 determines whether the currently required assist force output is equal to or less than a predetermined value (step S43), and if not equal to or less than the predetermined value, the assist force is gradually reduced (step S44). If not, the assist force is immediately reduced (step S45). Subsequently, the state is transitioned to "in failure diagnosis mode" (step S46), and the process returns.

If it is determined in step S41 that the system does not shift to the failure diagnosis mode, it is determined whether the currently required assist force output is equal to or less than a predetermined value (step S47). If it is equal to or less than the predetermined value (step S48), the assist force is immediately increased (step S49). Subsequently, the state is transitioned to “in assist force output mode” and “in other system in failure diagnosis mode” (step S50), and the process returns.

<Assist force output mode return processing>
FIG. 8 is a flow chart showing an example of the assist force output mode return process of steps S9 and S15 in FIG. In the assist force output mode return process, contrary to the above-described assist force output mode transition process, when the own system returns to the assist force output mode, an operation of gradually increasing the assist of another system is performed, and the other system assists When returning to the force output mode, an operation is performed to gradually reduce the assist of the own system.
First, the mode

switching function units

67 and 77 determine whether or not the own system is a system to return to the assist force output mode (step S51), and if it is a system to return to the assist force output mode, the assist force output mode return notification It transmits (step S52). Next, the assist control / external

command control unit

63, 73 determines whether the currently required assist force output is equal to or less than a predetermined value (step S53). If not, the assist force is gradually increased (step S54) If not, the assist force is immediately increased (step S55). Subsequently, the state is transitioned to "in the assist force output mode" (step S56), and the process returns.

If it is determined in step S51 that the system does not return to the assist force output mode, it is determined whether the currently required assist force output is equal to or less than a predetermined value (step S57). Gradually decrease (step S58), if it is less than a predetermined value, the assist force is immediately decreased (step S59). Subsequently, the state is transitioned to "in the assist force output mode" (step S56), and the process returns.

<Fault diagnosis process>
FIG. 9 is a flowchart showing an example of the failure diagnosis process of step S8 in FIG. In the failure diagnosis processing, first, it is determined whether or not failure diagnosis mode interruption information is stored in the non-volatile memory 69, 79 (step S61), and if not stored, the diagnosis target is set from the beginning (step S62) If it is stored, the diagnosis target is set from the point at which it was interrupted (step S63). In the next step S64, it is judged whether or not a failure diagnosis mode interruption request has been received from the

diagnostic function unit

66, 76 on the non-diagnostic side via the

inter-microcomputer communication unit

68, 78. The mode interruption information is stored in the non-volatile memory 69, 79 (step S74), and the process returns.

If it is determined in step S64 that the failure diagnosis mode interruption request has not been received, it is determined whether the diagnosis target affects the reception of signals from other systems (step S65). In this step S65, since it is desirable to perform diagnosis in a state in which CAN communication is maintained, diagnosis is not performed on a diagnosis target that can not perform CAN communication. Specifically, for example, diagnosis of a power supply IC in which a driver for CAN communication is built can not be performed.
If it is determined in step S65 that there is no influence, failure diagnosis is performed (step S66), and it is then determined whether a failure has occurred (step S67). If no failure occurs, and if it is determined in step S65 that there is an influence on signal reception from other systems, the diagnosis target is changed (step S68), and it is determined whether all failure diagnosis has been completed. It determines (step S69). If all the fault diagnoses have not been completed, the process returns to step S64 to repeat the above-described process. If all the fault diagnoses have been completed, the fault diagnostic mode interruption information (step S70) is deleted and the process returns. .

If it is determined in step S67 that a failure has occurred, the state transitions to a failure state (step S71), and the failure is transferred to another system (vehicle-mounted device controlled by an ECU other than the EPS control ECU) The notification is given (step S72), the failure is notified to the control module for external communication (step S73), and the process proceeds to step S70.
According to the configuration as described above, in the control device of the power steering apparatus of the redundant configuration including the drive units of the first and second systems, when the drive unit of one system is in the assist mode, the drive of the other system is performed. The diagnostics of the unit's pre-driver, inverter, motor relay or power supply relay can be performed and the opportunity for these diagnostics can be increased. Therefore, the diagnostic range during driving of the vehicle can be expanded, early detection and notification of a failure can be performed, and safety can be improved.

Second Embodiment
FIG. 10A is a functional block diagram of a control device of a power steering apparatus according to a second embodiment of the present invention. 10B and 10C respectively show configuration examples of the first and second microcontrollers in FIG. 10A. The second embodiment differs from the above-described first embodiment in that the

CAN communication units

62 and 72 are connected to other ECUs or vehicle-mounted devices via the

CAN buses

53a and 53b, respectively. It is a point. The other configuration is the same as that of the first embodiment. Therefore, in FIG. 10A, FIG. 10B and FIG. 10C, the same components as in FIG. 3A, FIG. 3B and FIG. Is omitted.
According to such a configuration, the drive units EPP1 and EPP2 can independently perform CAN communication by making the

CAN communication units

62 and 72 and the

CAN buses

53a and 53b redundant, so that one drive unit Even in the failure diagnosis mode, the other drive unit can perform CAN communication with the outside.

Third Embodiment
FIG. 11 is a functional block diagram of a control device of a power steering apparatus according to a third embodiment of the present invention. The third embodiment is different from the first embodiment described above in that the three drive units EPP1, EPP2, EPP3 drive the winding

sets

13a, 13b, 13c of the electric motor 13, respectively. is there. Although the detailed configuration is omitted in FIG. 11, the configuration of each of the drive units EPP1 and EPP2 is substantially the same as that of the first embodiment shown in FIGS. 3A, 3B and 3C. The drive unit EPP3 is substantially similar to the drive unit EPP2. Then, each of the microcontrollers 32, 36-1 and 36-2 communicates via the inter-microcomputer communication unit to drive the electric motor 13.

According to such a configuration, the first and second drive units EPP1 and EPP2 carry the assist force output during a period in which the required assist force output during driving of the vehicle is small, and the failure diagnosis of the third drive unit EPP3 is performed. It is possible to make a transition to the mode to diagnose the drive circuit DR3 or the power supply circuit.
As described above, even if the drive unit (ECU) is tripled and any system is in failure diagnosis mode, the drive unit in the assist force output mode can ensure redundant configuration, and all the driving situations depending on the output distribution of the assist force Transition to the fault diagnosis mode is possible.
Of course, four or more multiplex drive units may be provided.

Fourth Embodiment
FIG. 12A is a functional block diagram of a control device of a power steering apparatus according to a fourth embodiment of the present invention. 12B and 12C respectively show configuration examples of the first and second microcontrollers in FIG. 12A. In the fourth embodiment, the communication network in the second embodiment described above is changed from CAN to Ethernet (registered trademark). That is,

Ethernet communication units

62a and 72a are provided instead of

CAN communication units

62 and 72, and

Ethernet buses

53c and 53d are provided instead of

CAN buses

53a and 53b, respectively, and are connected to other ECUs or vehicle-mounted devices . Since the other configuration is the same as that of the second embodiment, in FIGS. 12A, 12B, and 12C, the same components as those in FIGS. 10A, 10B, and 10C are denoted by the same reference numerals. Is omitted.
According to such a configuration, since the existing protocol is used, access to the Internet is facilitated in addition to the improvement of the communication speed. As a result, the system can be extended to a system that is equipped with an information communication system that can communicate with the Internet, called a connected car, or cooperate with devices such as smartphones and tablets.

Fifth Embodiment
FIG. 13A is a functional block diagram of a control device of a power steering apparatus according to a fifth embodiment of the present invention. 13B and 13C respectively show configuration examples of the first and second microcontrollers in FIG. 13A. In the fifth embodiment, the communication network in the second embodiment described above is changed from CAN to FlexRay (registered trademark). That is,

FlexRay communication units

62b and 72b are provided instead of

CAN communication units

62 and 72, and

FlexRay buses

53e and 53f are provided instead of

CAN buses

53a and 53b, respectively, and are connected to other ECUs or vehicle-mounted devices . The other configuration is the same as that of the second embodiment, so in FIGS. 13A, 13B and 13C, the same components as in FIGS. 10A, 10B and 10C are denoted by the same reference numerals and detailed description thereof. Is omitted.
According to such a configuration, by using the in-vehicle network communication protocol "FlexRay", the transfer speed can be improved, the flexibility of the network configuration can be improved, and the reliability can be improved as compared with the CAN communication.

As described above, in a control device of a power steering apparatus using a plurality of sensors and a plurality of CPUs, it is possible to improve safety and stability by expanding the scope of failure diagnosis and early detection and notification of a failure even while driving. Become. In particular, in the case of a vehicle that performs automatic driving, by maintaining coordination with other systems even when a failure occurs during automatic driving, vehicle control can be maintained, and a highly reliable system can be achieved.

Here, technical ideas that can be grasped from the above-described embodiments will be described together with their effects.
In one aspect thereof, a control device of a power steering device includes an electric motor for applying a steering force to a steering wheel, and the control device of a power steering device for outputting a command signal for driving the electric motor A first drive circuit including a first inverter for driving and controlling a motor; a second drive circuit including a second inverter for driving and controlling the electric motor; a first power supply circuit for supplying power to the first inverter; A second power supply circuit for supplying power to a second inverter, a first microprocessor, a first motor command signal calculation unit, a first diagnosis unit, a first inter-microcomputer communication unit, and a first mode switching control And the first motor command signal calculation unit is configured to control the first motor command signal for driving and controlling the electric motor based on a signal related to the driving state of the vehicle. It outputs to a drive circuit, The said 1st diagnostic part diagnoses the presence or absence of any abnormality in at least said 1st drive circuit, said 1st power supply circuit, or said 1st microprocessor. The first mode switching control unit switches between a first assist mode and a first diagnosis mode, and in the first assist mode, the first motor command signal operation unit controls the first motor command signal. Is calculated, and the first motor command signal is output to the first drive circuit, and in the first diagnosis mode, the first diagnosis unit includes at least the first drive circuit, and the first power circuit. Or the first microprocessor and the second microprocessor in a state of diagnosing the presence or absence of an abnormality of any one of the first microprocessors, wherein the second motor command signal Unit, a second diagnosis unit, a second microcomputer communication unit, and a second mode switching control unit, wherein the second motor command signal calculation unit controls the drive of the electric motor based on a signal related to the driving state of the vehicle A second motor command signal to the second drive circuit, and the second diagnosis unit is configured to at least one of the second drive circuit, the second power supply circuit, and the second microprocessor. The second mode switching control unit switches between the second assist mode and the second diagnosis mode, and the first mode switching control unit is configured to diagnose the presence or absence of an abnormality of When the assist mode is selected, the second diagnostic mode can be selected, and in the second assist mode, the second motor command signal calculation unit calculates the second motor command signal, and 2 A state in which a motor command signal is output to the second drive circuit, wherein in the second diagnostic mode, the second diagnostic unit at least outputs the second drive circuit, the second power supply circuit, or the second microprocessor And the second microprocessor, which is in a state of diagnosing the presence or absence of any one of the above.
According to the above configuration, in a redundant system system having a plurality of microprocessors, drive circuits, and power supply circuits, when one system is in the assist mode, the drive circuit or the power supply circuit is diagnosed in the other system. The opportunity for diagnosis of the power supply circuit can be increased, and the safety of the device can be improved.

In a preferred aspect of a control device of a power steering apparatus, the first drive circuit includes the first inverter, a first predriver, and a first motor relay, and the first predriver is based on the first motor command signal. The first motor relay has a function to shut off the power supply to the electric motor, and the first power supply circuit includes a battery of the vehicle and the first inverter. Between the second inverter and the second motor, and the second drive circuit includes the second inverter, the second predriver, and the second motor relay, and the second predriver includes the second inverter, the second predriver, and the second motor relay. Is for driving the second inverter based on the second motor command signal, and the second motor relay supplies power to the electric motor Those having a blocking function, the second power supply circuit is provided between the vehicle battery and the second inverter, and wherein the one having a function of shutting off the power supply to the inverter.
According to the above configuration, the diagnosis opportunities of the above configuration can be increased by the first and second diagnosis units, and the safety of the device can be improved.

In still another preferable aspect, the second mode switching control unit selects the second diagnostic mode when the first motor command signal calculation unit does not output the first motor command signal to the first drive circuit. It is characterized by
According to the above configuration, it is possible to safely diagnose the apparatus by selecting the diagnosis mode when it is determined that the application of the steering force (steering assist) is unnecessary and the motor command signal is not output.

In still another preferable aspect, the second mode switching control unit selects the second diagnostic mode when the vehicle speed is equal to or higher than a first predetermined speed.
According to the above configuration, it is not necessary to apply a large steering force at the time of high speed traveling, and therefore, it is possible to suppress an increase in the driver's steering load due to the steering force not being applied in the system performing diagnosis. it can.

In still another preferred aspect, the second mode switching control unit selects the second diagnostic mode when the vehicle speed is equal to or less than a second predetermined speed.
According to the above configuration, the steering force in the system performing the diagnosis by selecting the diagnosis mode in a situation where the need for applying the steering force is low, such as during parking, pausing at an intersection, idling stop, etc. It is possible to suppress an increase in the driver's steering load due to the absence of the provision of.

In still another preferable aspect, the power steering apparatus includes a steering mechanism, and the steering mechanism steers the steered wheel along with a steering shaft that rotates based on a driver's steering operation and the steering shaft. A steering shaft is included, the electric motor applies a steering force to the steered wheels through the steering mechanism, and the signal related to the driving state of the vehicle is a signal of a steering angle or a signal of a steering torque. The signal of the steering angle is a signal of the rotation angle of the steering shaft, the signal of the steering torque is a signal of a torque generated in the steering mechanism, and the second mode switching control unit Is selected, or the second diagnosis mode is selected when the steering torque signal is less than a predetermined steering torque.
According to the above configuration, in a situation where the need for applying a large steering force is low, selecting a diagnosis mode increases the driver's steering load due to the fact that no steering force is applied in the system performing diagnosis. Can be suppressed.

In still another preferable aspect, the signal related to the driving state of the vehicle is a signal related to equipment other than the power steering device mounted on the vehicle, and the second mode switching control unit is the power steering device mounted on the vehicle The second diagnostic mode is selected based on signals relating to devices other than the above.
According to the above configuration, it is determined by the signals of other related devices that the need for applying a large steering force is low, whereby the driver is not given the application of steering force in the system performing diagnosis. An increase in steering load can be suppressed. Signals of other related devices include an engine rotation number signal, a transmission position signal, a brake pedal stroke signal, a yaw rate sensor, a vehicle speed signal, and the like.

In still another preferable aspect, the first mode switching control unit is selecting the first assist mode, and the second mode switching control unit is selecting the second diagnostic mode, and the second mode When the switching control unit determines that switching to the second assist mode is necessary, the second diagnosis unit cancels the diagnosis of the second drive circuit, the second power supply circuit, or the second microprocessor. At the same time, the second motor command signal calculation unit is characterized in that the output of the second motor command signal to the drive circuit is started.
According to the above configuration, when it is determined that the application of a larger steering force is necessary, the diagnostic mode is switched to the assist mode to apply the steering force according to the situation, thereby suppressing an increase in the driver's steering load. can do.

In still another preferable aspect, the power steering apparatus includes a steering mechanism, and the steering mechanism steers the steered wheel along with a steering shaft that rotates based on a driver's steering operation and the steering shaft. A steering shaft is included, the electric motor applies a steering force to the steered wheels through the steering mechanism, and a signal related to an operating state of the vehicle is a signal of a steering torque, the steering torque Is a signal of torque generated in the steering mechanism, and the second mode switching control unit selects the second assist mode when the signal of the steering torque is equal to or greater than a predetermined steering torque. .
According to the above-described configuration, the steering torque is one of the indicators that best represents the driver's steering load. Therefore, more appropriate mode switching is performed by switching the diagnosis mode and the assist mode based on the steering torque signal. be able to.

In still another preferable aspect, the second diagnostic unit further determines the presence or absence of an abnormality of the first microprocessor, and the second diagnostic unit determines that the first microprocessor has an abnormality. At the same time, the second mode switching control unit selects the second assist mode.
According to the above configuration, when there is an abnormality in the first microprocessor, there is a possibility that the first motor command signal calculation unit can not apply an appropriate steering force, so by selecting the second assist mode, Even when an abnormality occurs in the first microprocessor, an increase in the steering load of the driver can be suppressed.

In still another preferable aspect, the second microprocessor includes a second diagnostic status storage unit, and the second diagnostic status storage unit stores a diagnostic status in the second diagnostic unit, and 2) The diagnosis unit temporarily suspends the diagnosis while performing diagnosis of the second drive circuit, the second power supply circuit, or the second microprocessor, and then restarts the diagnosis after that; 2) The diagnosis is resumed based on the diagnosis status stored in the diagnosis status storage unit.
According to the above configuration, the diagnosis is temporarily suspended in the middle of the diagnosis, and when the restart is resumed, the diagnostic status at the time of suspension is stored, and when the restart is performed, the diagnosis is repeated by continuing the diagnosis. Can be suppressed and efficient diagnosis can be performed.

In still another preferred aspect, a control device of a power steering apparatus includes a third drive circuit, a third power supply circuit, and a third microprocessor, and the third drive circuit drives and controls the electric motor. An inverter is included, and the third power supply circuit supplies power to the third inverter, and the third microprocessor includes a third motor command signal calculation unit, a third diagnosis unit, and a third diagnosis unit. The third motor command signal calculation unit includes a third motor command signal for driving and controlling the electric motor based on a signal related to the driving state of the vehicle. The third diagnostic unit outputs at least the third drive circuit, the third power supply circuit, or the third microprocessor. The third mode switching control unit is configured to switch between a third assist mode and a third diagnosis mode, and the first mode switching control unit is configured to perform the first assist mode. When it is selected or when the second mode switching control unit selects the second assist mode, the third diagnostic mode can be selected, and the third assist mode is the third assist mode. The motor command signal calculation unit calculates the third motor command signal and outputs the third motor command signal to the third drive circuit, and the third diagnosis unit in the third diagnosis mode is: It is characterized in that it is in a state of diagnosing the presence or absence of any one of at least the third drive circuit, the third power supply circuit, and the third microprocessor.
According to the above configuration, the control device includes the third drive circuit, the third power supply circuit, and the third microprocessor so that the remaining two microprocessors can be selected even if one microprocessor is selecting the diagnostic mode. Can configure a redundant system.

In still another preferred aspect, the third mode switching control unit can select the third diagnostic mode regardless of the driving state of the vehicle.
According to the above configuration, even if one microprocessor is selecting a diagnostic mode, a redundant system can be configured by the remaining two microprocessors, so that the diagnostic mode is selected regardless of the operating state. be able to.

In still another preferable aspect, when the second diagnostic unit starts diagnosis of the second drive circuit, the second power supply circuit, or the second microprocessor, the second motor command signal calculation unit is configured to: The first motor command signal calculation unit is characterized in that the torque value instructed by the first motor command signal is increased while the torque value instructed by the second motor command signal is decreased.
According to the above configuration, with the start of the diagnosis of the second diagnosis unit, the ratio of the steering power assistance on the second microprocessor side is decreased, and the ratio of the steering power assistance on the first microprocessor side is increased. The decrease in the steering force on the microprocessor and the second drive circuit side can be compensated by the increase in the steering force on the first microprocessor and the first drive circuit side, and the increase in the steering load of the driver can be suppressed.

In still another preferable aspect, when the second diagnostic unit starts diagnosis of the second drive circuit, the second power supply circuit, or the second microprocessor, the second motor command signal calculation unit is configured to: (2) The torque value instructed by the motor command signal is gradually decreased, and the first motor command signal calculating unit is characterized by gradually increasing the torque value instructed by the first motor command signal.
According to the above configuration, with the start of the diagnosis of the second diagnosis unit, the ratio of the steering assist by the second microprocessor and the second drive circuit is reduced, and the steering assist by the first microprocessor and the first drive circuit By gradually changing the output when increasing the ratio of V, it is possible to suppress the occurrence of steering discomfort due to the change of the steering force.

In still another preferable aspect, the power steering apparatus includes a steering mechanism, and the steering mechanism steers the steered wheel along with a steering shaft that rotates based on a driver's steering operation and the steering shaft. A steering shaft is included, the electric motor applies a steering force to the steered wheels via the steering mechanism, and a signal related to an operating state of the vehicle is a signal of a steering torque, The signal is a signal of torque generated in the steering mechanism, and when the second diagnostic unit starts diagnosis of the second drive circuit, the second power circuit, or the second microprocessor, When the steering torque signal is less than a predetermined value, the second motor command signal calculation unit decreases the torque value instructed by the second motor command signal, and calculates the first motor command signal. It is characterized by increasing the torque value indicated by the first motor command signal.
According to the above configuration, when the value of the steering torque is small, the steering assist force is also small. Therefore, by changing the ratio of the steering force on the first microprocessor, the first drive circuit side and the second microprocessor, and the second drive circuit side The change in output is also small. Therefore, the occurrence of steering discomfort can be suppressed.

In still another preferred aspect, a control device of a power steering device includes a first transceiver, a first controller, a second transceiver, and a second controller, and the vehicle includes a bus and a vehicle control device other than the power steering device. The first transceiver is connected to the bus and transmits / receives signals to / from the bus, and the first controller transmits / receives signals to / from the first transceiver. The second transceiver is connected to the bus, and transmits and receives signals to and from the bus, and the second controller transmits and receives signals to and from the second transceiver. In the first transceiver, the first diagnosis unit is the first drive circuit, and the first power circuit Alternatively, when a first abnormality that is an abnormality of the first microprocessor is detected, a signal relating to the first abnormality is transmitted to the vehicle control device, and the second transceiver is configured to transmit the second diagnostic unit. A signal related to the second abnormality is transmitted to the vehicle control device when a second abnormality that is an abnormality of the drive circuit, the second power supply circuit, or the second microprocessor is detected.
According to the above configuration, the second vehicle control device can appropriately cope with the second abnormality by sharing information with the second vehicle control device regarding the second abnormality.

In still another preferable aspect, the vehicle control device is a control module for external communication that transmits a signal to an apparatus other than the vehicle, and the signal regarding the second abnormality received from the first transceiver or the second transceiver. Are transmitted to devices other than the vehicle.
According to the above configuration, by transmitting the information to the device other than the vehicle, for example, the network of the vehicle service, regarding the second abnormality, it is possible to receive the prompt and appropriate vehicle service for the second abnormality.

In still another preferred aspect, the first diagnostic circuit is configured to transmit the first drive circuit when at least one of the first transceiver and the second transceiver can transmit and receive signals to and from the bus. And diagnosing the presence or absence of an abnormality of the first power supply circuit or the first microprocessor, and the second diagnostic unit is configured to communicate signals between at least one of the first transceiver and the second transceiver with the bus. When in a state capable of transmission and reception, it is characterized in that presence or absence of abnormality of the second drive circuit, the second power supply circuit, or the second microprocessor is diagnosed.
According to the above configuration, the first and second diagnosis units can perform appropriate diagnosis based on the signals from the other on-vehicle devices acquired via the bus. Alternatively, a signal can be transmitted to another vehicle-mounted device regarding the occurrence of the second abnormality. For example, when an abnormality occurs in the first drive circuit in a situation where the first transceiver can not transmit / receive signals to / from the bus, the first drive circuit via the communication unit between the first and second microcomputers The second abnormality signal can be transmitted to the second microprocessor side, and the second transceiver can transmit a second abnormality signal to another vehicle-mounted device.

3 ... ECU for EPS control, 10 ... power steering device, 13 ... electric motor, 13a, 13b, 13c ... winding assembly, 29, 30 ... power supply relay (power supply circuit), 31 ... battery, 32 ... first microcontroller (the first microcontroller) First microprocessor), 33 ... predriver (first predriver), 36 ... second microcontroller (second microprocessor), 37 ... predriver (second predriver), 40 ... inverter (first inverter), DESCRIPTION OF SYMBOLS 41 ... Inverter (2nd inverter) 44 ... Motor relay (1st motor relay) 46 ... Motor relay (2nd motor relay) 53, 53a, 53b ... CAN bus, 53c, 53d ... Ethernet bus, 53e, 53f ... FlexRay bus, 54 ... first sensor, 55 ... second sensor, 61 ... input signal processing unit, 62, 72 ... AN

communication unit

62a, 72a: Ethernet communication unit, 62b, 72b: FlexRay communication unit, 63: assist control / external command control unit, 65: motor control unit, 66: diagnosis function unit (first diagnosis unit), 67: Mode switching function unit (first mode switching control unit) 68, 78 Inter-microcomputer communication unit 71 Input signal processing unit 73 Assist control / external command control unit 75 Motor control unit 76 Diagnostic function unit (Second diagnostic unit) 77: Mode switching function unit (second mode switching control unit) EPP1, EPP2, EPP3: Drive unit

Claims

A control device for a power steering device, wherein the power steering device includes an electric motor for applying a steering force to steering wheels, and the control device for the power steering device for outputting a command signal for driving the electric motor.
A first drive circuit including a first inverter for driving and controlling the electric motor;
A second drive circuit including a second inverter for driving and controlling the electric motor;
A first power supply circuit for supplying power to the first inverter;
A second power supply circuit for supplying power to the second inverter;
A first microprocessor comprising a first motor command signal calculation unit, a first diagnosis unit, a first inter-microcomputer communication unit, and a first mode switching control unit;
The first motor command signal calculation unit outputs, to the first drive circuit, a first motor command signal for driving and controlling the electric motor based on a signal related to a driving state of a vehicle.
The first diagnosis unit diagnoses the presence or absence of any abnormality among at least the first drive circuit, the first power supply circuit, or the first microprocessor.
The first mode switching control unit switches between a first assist mode and a first diagnostic mode.
The first assist mode is a state in which the first motor command signal calculation unit calculates the first motor command signal and outputs the first motor command signal to the first drive circuit.
The first diagnostic mode is a state in which the first diagnostic unit diagnoses at least one of the first drive circuit, the first power circuit, and the first microprocessor for abnormality.
The first microprocessor;
A second microprocessor, comprising a second motor command signal operation unit, a second diagnosis unit, a second inter-microcomputer communication unit, and a second mode switching control unit;
The second motor command signal calculation unit outputs, to the second drive circuit, a second motor command signal for driving and controlling the electric motor based on a signal related to a driving state of a vehicle.
The second diagnosis unit diagnoses the presence or absence of any abnormality among at least the second drive circuit, the second power supply circuit, or the second microprocessor,
The second mode switching control unit switches between a second assist mode and a second diagnosis mode, and the second mode switching control unit selects the first assist mode when the first mode switching control unit selects the first assist mode. The diagnostic mode can be selected,
The second assist mode is a state in which the second motor command signal calculation unit calculates the second motor command signal and outputs the second motor command signal to the second drive circuit.
The second diagnostic mode is a state in which the second diagnostic unit diagnoses the presence or absence of at least one of the second drive circuit, the second power circuit, and the second microprocessor.
The second microprocessor;
And a control device for a power steering device.
The control device for a power steering apparatus according to claim 1, wherein the first drive circuit includes the first inverter, a first predriver, and a first motor relay.
The first predriver drives the first inverter based on the first motor command signal,
The first motor relay has a function of interrupting power supply to the electric motor,
The first power supply circuit is provided between a battery of a vehicle and the first inverter, and has a function of interrupting power supply to the inverter.
The second drive circuit includes the second inverter, a second predriver, and a second motor relay.
The second pre-driver drives the second inverter based on the second motor command signal,
The second motor relay has a function of interrupting power supply to the electric motor,
A control device for a power steering apparatus, wherein the second power supply circuit is provided between a battery of a vehicle and the second inverter, and has a function to shut off the power supply to the inverter.
The control device of a power steering apparatus according to claim 1, wherein the second mode switching control unit, when the first motor command signal calculation unit does not output the first motor command signal to the first drive circuit, A control device of a power steering device, which selects the second diagnostic mode.
The power steering apparatus according to claim 3, wherein the second mode switching control unit selects the second diagnosis mode when the vehicle speed is equal to or higher than a first predetermined speed. Control device.
The power steering apparatus according to claim 3, wherein the second mode switching control unit selects the second diagnostic mode when the vehicle speed is equal to or lower than a second predetermined speed. Control device.
The control device of a power steering device according to claim 3, wherein the power steering device includes a steering mechanism,
The steering mechanism includes a steering shaft that rotates based on a driver's steering operation, and a steered shaft that steers the steered wheels as the steering shaft rotates.
The electric motor applies a steering force to the steered wheels via the steering mechanism,
The signal related to the driving state of the vehicle is a signal of a steering angle or a signal of a steering torque,
The signal of the steering angle is a signal of the rotation angle of the steering shaft,
The steering torque signal is a torque signal generated in the steering mechanism,
A power steering apparatus characterized in that the second mode switching control unit selects the second diagnosis mode when the signal of the steering angle is less than a predetermined steering angle or the signal of the steering torque is less than a predetermined steering torque. Control device.
4. The control device for a power steering device according to claim 3, wherein the signal related to the driving state of the vehicle is a signal related to equipment other than the power steering device mounted on the vehicle,
A power steering apparatus characterized in that the second mode switching control unit selects the second diagnostic mode based on a signal related to an apparatus other than the power steering apparatus mounted on a vehicle.
The control device for a power steering apparatus according to claim 1, wherein the first mode switching control unit is selecting the first assist mode, and the second mode switching control unit is selecting the second diagnostic mode. When the second mode switching control unit determines that switching to the second assist mode is necessary, the second diagnostic unit is configured to determine whether the second drive circuit, the second power supply circuit, or the (2) A control device of a power steering apparatus characterized in that the diagnosis of the microprocessor is stopped and the second motor command signal operation unit starts outputting the second motor command signal to the drive circuit.
The control device for a power steering apparatus according to claim 8, wherein the power steering apparatus includes a steering mechanism,
The steering mechanism includes a steering shaft that rotates based on a driver's steering operation, and a steered shaft that steers the steered wheels as the steering shaft rotates.
The electric motor applies a steering force to the steered wheels via the steering mechanism,
The signal related to the driving state of the vehicle is a signal of steering torque, and
The steering torque signal is a torque signal generated in the steering mechanism,
The control device of a power steering apparatus, wherein the second mode switching control unit selects the second assist mode when the signal of the steering torque is equal to or more than a predetermined steering torque.
9. The control device for a power steering apparatus according to claim 8, wherein the second diagnosis unit further determines the presence or absence of an abnormality of the first microprocessor,
The control device of a power steering apparatus, wherein the second mode switching control unit selects the second assist mode when the second diagnosis unit determines that the first microprocessor is abnormal.
9. The control device for a power steering apparatus according to claim 8, wherein the second microprocessor includes a second diagnosis status storage unit.
The second diagnostic status storage unit stores the diagnostic status in the second diagnostic unit, and
The second diagnostic unit temporarily suspends the diagnosis during the diagnosis of the second drive circuit, the second power supply circuit, or the second microprocessor, and then resumes the diagnosis after that. A control apparatus for a power steering apparatus, wherein the diagnosis is resumed based on the diagnosis status stored in the second diagnosis status storage unit.
The control device of the power steering apparatus according to claim 1 includes a third drive circuit, a third power supply circuit, and a third microprocessor.
The third drive circuit includes a third inverter that drives and controls the electric motor,
The third power supply circuit supplies power to the third inverter,
The third microprocessor includes a third motor command signal calculation unit, a third diagnosis unit, a third inter-microcomputer communication unit, and a third mode switching control unit.
The third motor command signal calculation unit outputs, to the third drive circuit, a third motor command signal for driving and controlling the electric motor based on a signal related to a driving state of a vehicle.
The third diagnosis unit diagnoses the presence or absence of any abnormality among at least the third drive circuit, the third power supply circuit, or the third microprocessor.
The third mode switching control unit switches between a third assist mode and a third diagnosis mode, and the first mode switching control unit selects the first assist mode, or When the second mode switching control unit selects the second assist mode, the third diagnostic mode can be selected,
The third assist mode is a state in which the third motor command signal calculation unit calculates the third motor command signal and outputs the third motor command signal to the third drive circuit.
The third diagnosis mode is a state in which the third diagnosis unit diagnoses the presence or absence of any abnormality among at least the third drive circuit, the third power supply circuit, or the third microprocessor. The control device of the power steering device which is characterized.
The control device of a power steering device according to claim 12, wherein the third mode switching control unit is capable of selecting the third diagnosis mode regardless of the driving state of the vehicle. Control device.
The control device for a power steering apparatus according to claim 1, wherein the second diagnosis unit starts diagnosis of the second drive circuit, the second power circuit, or the second microprocessor, the second motor command. The signal operation unit decreases the torque value instructed by the second motor instruction signal, and the first motor instruction signal operation unit increases the torque value instructed by the first motor instruction signal. Control device for power steering device.
The control device of a power steering apparatus according to claim 14, wherein the second diagnosis unit starts diagnosis of the second drive circuit, the second power circuit, or the second microprocessor, the second motor command. The signal operation unit gradually decreases the torque value instructed by the second motor command signal, and the first motor command signal operation unit gradually increases the torque value instructed by the first motor command signal. Control device for power steering device.
The control device of a power steering device according to claim 14, wherein the power steering device includes a steering mechanism,
The steering mechanism includes a steering shaft that rotates based on a driver's steering operation, and a steered shaft that steers the steered wheels as the steering shaft rotates.
The electric motor applies a steering force to the steered wheels via the steering mechanism,
The signal related to the driving state of the vehicle is a signal of steering torque,
The steering torque signal is a torque signal generated in the steering mechanism, and
When the second diagnosis unit starts diagnosis of the second drive circuit, the second power supply circuit, or the second microprocessor, and the signal of the steering torque is less than a predetermined value, the second motor The command signal operation unit decreases the torque value instructed by the second motor command signal, and the first motor command signal operation unit increases the torque value instructed by the first motor command signal. The control device of the power steering device which is characterized.
The control device of the power steering apparatus according to claim 1 includes a first transceiver, a first controller, a second transceiver, and a second controller.
The vehicle includes a bus and a vehicle control device other than the power steering device.
The first transceiver is connected to the bus, and transmits and receives signals to and from the bus.
The first controller transmits and receives signals to and from the first transceiver,
The second transceiver is connected to the bus and transmits and receives signals to and from the bus.
The second controller transmits and receives signals to and from the second transceiver,
The first transceiver is a signal related to the first abnormality when the first diagnosis unit detects a first abnormality that is an abnormality of the first drive circuit, the first power supply circuit, or the first microprocessor. To the vehicle control device,
When the second diagnostic unit detects a second abnormality that is an abnormality of the second drive circuit, the second power supply circuit, or the second microprocessor, the second transceiver detects a signal related to the second abnormality. Control device for transmitting power to the vehicle control device.
The control device for a power steering device according to claim 17, wherein the vehicle control device is a control module for external communication that transmits a signal to a device other than the vehicle, and is received from the first transceiver or the second transceiver A control apparatus for a power steering apparatus, comprising: transmitting a signal relating to the second abnormality to an apparatus other than the vehicle.
The control device of a power steering apparatus according to claim 17, wherein the first diagnostic unit is in a state in which at least one of the first transceiver and the second transceiver can transmit and receive signals to and from the bus. When diagnosing the presence or absence of an abnormality of the first drive circuit, the first power supply circuit, or the first microprocessor;
The second drive circuit, the second power supply circuit, the second diagnosis unit, when at least one of the first transceiver and the second transceiver can transmit and receive signals to and from the bus, Alternatively, a control device of a power steering apparatus, which diagnoses the presence or absence of an abnormality of the second microprocessor.