JP6710614B2 - Motor control device and steering device - Google Patents

Description

The present invention relates to a motor control device and a steering device.

As a motor control device that controls the operation of a motor having a plurality of windings, for example, there is one described in Patent Document 1.
In Patent Document 1, in a vehicle steering system, two systems of a first motor having a first motor winding and a second motor having a second motor winding so as to apply power to a steering mechanism. Is provided with a steering control device for controlling the operation of the motor. In this steering control device, a first system configured by a first ECU provided in combination with a first drive circuit so as to supply a current to a first motor and a current supply to a second motor are provided. A second system configured by a second ECU provided in combination with the second drive circuit is provided. Note that the steering angle of the steering wheel is individually input as a position signal from the outside to each ECU, and a rotation angle sensor that detects the rotation angle of each motor is individually connected.

Specifically, the first ECU uses the position signal to generate a torque command value. The torque command value is distributed by the first ECU to the first ECU and the second ECU. Each ECU controls the operation of each drive circuit provided in combination based on the torque command value distributed by the first ECU, using the detection result of the rotation angle sensor connected to each ECU. ing. That is, a master-slave relationship is established in each ECU, with the first ECU as a master and the second ECU as a slave.

However, when an abnormality occurs in the first ECU such as a position signal externally input to the master first ECU or a detection result of the rotation angle sensor connected thereto, the second ECU causes the first system to rotate the first motor winding when the first ECU has an abnormality. The supply of electric current to them has been cut off. In this case, the second ECU that is a slave generates a torque command value using a position signal input from the outside, and controls the operation of the drive circuit using the detection result of the connected rotation angle sensor. That is, when the first ECU is abnormal, at least the second ECU continues to supply the current to the second motor winding, and the output for the second motor is secured.

JP 2004-182039 A

As described in Patent Document 1, when the first ECU that is the master is abnormal, the supply of current from the first ECU to the first motor winding is cut off, and the output for the first motor is lost. It becomes half of the total output of the first motor and the second motor under normal conditions. On the other hand, even when the first ECU, which is the master, is in an abnormal state, it is desired to suppress a decrease in the overall output of the first motor and the second motor. Such demands are not limited to those for applying power to the steering mechanism in the vehicle, and are the same as long as they control the operation of the motor.

The present invention has been made in view of these circumstances, and an object thereof is to provide a motor control device and a steering device that can suppress a decrease in the overall output of the motor even when the master is in an abnormal state.

A motor control device for solving the above problem includes a plurality of control systems for controlling the operation of a motor having windings of a plurality of systems, and each control system supplies a current to each of the windings of each system. It is configured to include each arithmetic unit provided in combination with each drive circuit, and to each arithmetic unit of each control system, an individual external command value is input from the outside, and the relationship between the master and slave is Has been built. In this motor control device, the master computing unit computes a current command value, which is a target of the amount of current supplied to the winding, using the external command value, and sends the current command value to the slave computing unit. Output. Further, the master arithmetic unit and the slave arithmetic unit are configured to respectively control the operation of the drive circuit of the control system to which they belong, based on the current command value. When an abnormality occurs in the external command value externally input to the master calculation unit, the external command value externally input to the slave calculation unit instead of the external command value is used to calculate the current command value. Is configured to be used.

When each arithmetic unit of each control system has a master-slave relationship as in the above configuration, when an external command value input from the outside to the master arithmetic unit is abnormal, the current command value is appropriately adjusted. It becomes impossible to perform such calculations. However, even if there is an abnormality in the external command value input from the outside to the master arithmetic unit, there is a case where the external command value externally input to the slave arithmetic unit is not abnormal.

Therefore, according to the above configuration, when an abnormality occurs in the external command value externally input to the master arithmetic unit, the external command value externally input to the slave arithmetic unit is detected instead of the external command value. By using the result, it becomes possible to continue the calculation of the current command value. As a result, even when the master is in an abnormal state, it is possible to suppress a decrease in the overall output of the motor.

Specifically, when an abnormality occurs in the external command value input from the outside to the master calculation unit, the slave calculation unit uses the external command value input from the outside instead of the master calculation unit to generate the current. It is configured to calculate a command value and output the current command value to the calculation unit of the master.

According to the above configuration, when an external command value externally input to the slave arithmetic unit is used instead of the external command value externally input to the master arithmetic unit, between the master arithmetic unit and the slave arithmetic unit. As for the movement of information, it is not necessary to move information back and forth between the arithmetic unit of the master and the arithmetic of the slave.

Thus, for example, when each arithmetic unit executes the periodic processing, after an abnormality occurs in the external command value input to the arithmetic unit of the master from the outside, the arithmetic unit of the master operates in the same cycle of the periodic processing. The command value can be obtained from the arithmetic unit of the slave. Therefore, the output of the motor can be appropriately controlled even when the master is abnormal.

In the above motor control device, the master arithmetic unit and the slave arithmetic unit can output information from the master arithmetic unit to the slave arithmetic unit, and the slave arithmetic unit can output information to the master arithmetic unit. It is connected via an interface having a state that enables output of information, and the interface is connected from the master arithmetic unit to the slave arithmetic unit when there is no abnormality in the external command value input from the outside to the master arithmetic unit. While the information can be output to the calculation unit, if an external command value input to the calculation unit of the master is abnormal, the slave calculation unit sends information to the master calculation unit. It is desirable that it is configured to enable output.

According to the above configuration, when an abnormality occurs in the external command value input to the master computing unit from the outside, the interface is used to output the current command value from the slave computing unit to the master computing unit. You can As a result, even if the overall output of the motor is suppressed from being reduced when the master is abnormal, the range of hardware changes such as the addition of interfaces can be reduced.

Further, in the above motor control device, the master calculation unit has an abnormality detection unit that detects an abnormality in an external command value input from the outside, and the abnormality detection unit is the master calculation unit. When an external command value input from the outside is abnormal, it is desirable that the information indicating the occurrence of the abnormality is output through the interface.

According to the above configuration, the abnormality detection unit can output information indicating that an abnormality has occurred, using an interface common to transmitting and receiving the current command value. As a result, even when the reduction of the overall motor output is suppressed when the master malfunctions, the range of hardware changes such as the addition of interfaces can be reduced more preferably.

These can be embodied in a steering device including a motor having a plurality of windings for applying power to steer the steered wheels of the vehicle, and the motor control device that controls the motor.

According to these configurations, it is possible to realize a motor control device capable of stabilizing the application of power by suppressing a decrease in the overall output of the motor even when the master is in an abnormal state. Then, in the steering device realized by using this motor control device, it is possible to improve the reliability in applying the power.

According to the present invention, it is possible to suppress a decrease in the overall output of the motor even when the master is abnormal.

The figure which shows the outline about one Embodiment of the electric power steering device which materialized the steering device. The block diagram which shows the electric constitution about the same electric power steering apparatus. The block diagram which shows the function of each arithmetic processing part about the motor control device of the electrical equipment power steering apparatus. The flowchart which shows the flow of the abnormality detection process which the abnormality detection part performs about the 1st arithmetic processing part and the 2nd arithmetic processing part of the same motor control device. The block diagram which shows the function of each arithmetic processing part when the abnormality has arisen in the 1st arithmetic processing part about the motor control device.

An embodiment of the motor control device and the steering device will be described below.
As shown in FIG. 1, the vehicle A is deviated from the lane while the vehicle A is traveling by applying power to the steering mechanism 2 described later to automatically change the traveling direction of the vehicle A. A vehicle steering system 1 that builds a lane departure prevention support system that prevents this is installed. In the present embodiment, the vehicle steering system 1 is an example of a steering device.

The steering mechanism 2 includes a steering wheel 10 operated by a user and a steering shaft 11 fixed to the steering wheel 10. The steering shaft 11 has a column shaft 11a connected to the steering wheel 10, an intermediate shaft 11b connected to the lower end of the column shaft 11a, and a pinion shaft 11c connected to the lower end of the intermediate shaft 11b. doing. The lower end of the pinion shaft 11c is connected to the rack shaft 12 via a rack and pinion mechanism 13. Rotational movement of the steering shaft 11 is converted into axial reciprocating linear movement of the rack shaft 12 via the rack and pinion mechanism 13. This reciprocating linear motion is transmitted to the left and right steered wheels 15 via the tie rods 14 connected to both ends of the rack shaft 12, respectively, so that the steered angles of these steered wheels 15 change.

An actuator 3 having a motor 20 that is a source of power to be applied to the steering mechanism 2 is provided in the middle of a column shaft 11 a fixed to the steering wheel 10. For example, the motor 20 is a surface magnet synchronous motor (SPMSM), and is a three-phase brushless motor that rotates based on three-phase (U, V, W) drive power. The rotating shaft 21 of the motor 20 is connected to the column shaft 11 a via a reduction mechanism 22. The actuator 3 transmits the rotational force of the rotary shaft 21 of the motor 20 to the column shaft 11 a via the speed reduction mechanism 22. The torque (rotational force) of the motor 20 applied to the column shaft 11a becomes power (steering force), and changes the steered angles of the left and right steered wheels 15.

As shown in FIG. 2, the motor 20 includes a rotor 23 that rotates about its rotation shaft 21 and a stator 24 that is arranged on the outer periphery of the rotor 23. A permanent magnet is fixed to the surface of the rotor 23. The permanent magnets are arranged such that different polarities (N pole, S pole) are alternately arranged in the circumferential direction of the rotor 23. Such a permanent magnet forms a magnetic field, that is, a field when the motor 20 rotates. A plurality of windings 25 of three phases (U phase, V phase, W phase) are annularly arranged on the stator 24. The winding 25 is classified into a first system winding 26 and a second system winding 27. The first system winding 26 and the second system winding 27 are star-connected. The system windings 26 and 27 are arranged such that the windings of the respective phases are alternately arranged along the circumference of the stator 24 for each system, or the windings of the respective phases are arranged along the circumference of the stator 24. They may be collectively arranged side by side, or may be laminated and arranged in the same tooth in the radial direction of the stator 24.

Returning to the description of FIG. 1, the actuator 3 is connected to a motor control device 30 that controls the operation (drive) of the motor 20 by controlling the amount of current that is the control amount of the motor 20. The motor control device 30 controls the operation of the motor 20 based on the detection results of various sensors provided in the vehicle A. The various sensors include, for example, two (individual) torque sensors 50, 51 and two (individual) rotation angle sensors 52, 53.

The torque sensors 50 and 51 are provided on the column shaft 11a, and the rotation angle sensors 52 and 53 are provided on the motor 20. The torque sensors 50 and 51 detect torque values Tm1 and Tm2, which are values indicating the magnitude and direction of the steering torque that is the load applied to the steering shaft 11 by the user's steering operation. The rotation angle sensors 52 and 53 detect the rotation angles θm1 and θm2 of the rotation shaft 21 of the motor 20, respectively. It should be noted that there is a correlation between the respective rotation angles θm1 and θm2, and the rotation angle of the column shaft 11a and the steering angle of the steered wheels 15 that are interlocked with the user's steering operation. By processing the rotation angles θm1 and θm2 and multiplying them by the conversion factor, the rotation angle of the column shaft 11a and the steering angle of the steered wheels 15, that is, the actual angle can be calculated.

The torque sensors 50 and 51 have the same configuration, and are, for example, Hall ICs (elements) that output a digital value according to the steering torque. Each of the torque sensors 50 and 51 has the column shaft 11a as a detection target, and when both are normal, outputs substantially the same digital value. As a result, the torque sensors 50 and 51, that is, the steering torque information that is the detection result of these torque sensors 50 and 51 are made redundant. Similarly, the rotation angle sensors 52 and 53 have the same configuration and are, for example, Hall ICs (elements) that output digital values according to the rotation angle of the rotation shaft 21 of the motor 20. Each of the rotation angle sensors 52 and 53 has the rotation axis 21 as a detection target, and when both are normal, outputs substantially the same digital value. As a result, the rotation angle sensors 52 and 53, that is, the information on the rotation angle that is the detection result thereof, is made redundant.

Further, the motor control device 30 is connected to an on-vehicle host control device 40. The host controller 40 instructs the motor controller 30 to perform automatic steering control (lane keeping control) that automatically changes the traveling direction of the vehicle A.

The host control device 40 is based on the detection result of the vehicle surrounding environment detection unit 54 by GPS or other on-vehicle sensors (camera, distance sensor, yaw rate sensor, laser, etc.) provided in the vehicle A, such as a car navigation system, or vehicle-to-vehicle communication. , Two (individual) angle command values θs1* and θs2* used for automatic steering control are calculated for each predetermined period. Then, the host controller 40 individually outputs the calculated angle command values θs1*, θs2* to the motor controller 30 at predetermined intervals. In the present embodiment, the angle command values θs1* and θs2* are examples of external command values.

The vehicle surrounding environment detection unit 54 detects the vehicle surrounding environment from various sensors, and calculates the angle information θv based on these. The angle information θv is, for example, the relative direction of the vehicle A with respect to the road. This is a component (state quantity) indicating the traveling direction of the vehicle A, and is the steering angle of the steered wheels 15 with respect to the straight traveling direction of the vehicle A. Therefore, the respective rotation angles θm1 and θm2 that can be converted into the steering angle of the steered wheels 15 are components indicating the actual traveling direction of the vehicle A. The angle command values θs1* and θs2* used for the automatic steering control are target values of components indicating the traveling direction of the vehicle A. The angle command values θs1* and θs2* are, in principle, the same value, and the information of the angle command value of the automatic steering control is made redundant.

A changeover switch (not shown) is connected to the motor control device 30. The changeover switch is operated by the user, and instructs the motor control device 30 to switch whether or not to set the automatic steering mode for executing the automatic steering control. The motor control device 30 executes the automatic steering control while the setting of the automatic steering mode is instructed, and interrupts the automatic steering control if the steering operation is intervened by the user (hereinafter referred to as “intervention operation”). Executes intervention control to assist steering operation. Further, the motor control device 30 does not execute the automatic steering control while the setting of the automatic steering mode is not instructed (while the setting is not instructed), and executes the assist control for assisting the steering operation. In this case, the motor control device 30 invalidates the respective angle command values θs1*, θs2* output by the higher-level control device 40.

Next, the electrical configuration of the vehicle steering system 1 will be described together with the function of the motor control device 30.
As shown in FIG. 2, the motor control device 30 includes a first electronic control device 31 (hereinafter, referred to as “first ECU” that configures a control system that supplies a current (driving power) to the first system winding 26 of the motor 20. And a second electronic control unit 32 (hereinafter, referred to as “second ECU”) that constitutes a control system that supplies a current (driving power) to the second system winding 27 of the motor 20. .. Each of the electronic control units 31 and 32 is an ECU (Electronic Control Unit) that constitutes a control system independent of each other.

A torque sensor 50 and a rotation angle sensor 52 are connected to the first ECU 31. The torque value Tm1 is input from the torque sensor 50 to the first ECU 31 via the interface com11 (communication line), and the rotation angle θm1 is input from the rotation angle sensor 53. The angle command value θs1* is input to the first ECU 31 from the host controller 40 via the interface com12 (communication line). Similarly, the torque sensor 51 and the rotation angle sensor 53 are connected to the second ECU 32. The torque value Tm2 is input from the torque sensor 51 to the second ECU 32 via the interface com21 (communication line), and the rotation angle θm2 is input from the rotation angle sensor 53. The angle command value θs2* is input to the second ECU 32 from the host controller 40 via the interface com22 (communication line). It should be noted that each of the ECUs 31 and 32 is connected to an individual DC power source for supplying a current to each of the system windings 26 and 27.

In the motor control device 30, each of the ECUs 31 and 32 can transmit and receive information to and from each other via an interface com13 (communication line) provided in the first ECU 31 and an interface com23 (communication line) provided in the second ECU 32. It is connected to the. A plurality of pieces of information including at least a torque command value and a rotation angle, which will be described later, are transmitted from the first ECU 31 to the second ECU 32 in one direction at a time through serial communication or the like via the interfaces com13 and com23. , Is transmitted from the second ECU 32 in one direction to the first ECU 31 at one time.

The first ECU 31 has a first calculation processing section 310, a first drive circuit 311, a first current sensor 312, and a first angle calculation section 313. The second ECU 32 also includes a second arithmetic processing unit 320, a second drive circuit 321, a second current sensor 322, and a second angle arithmetic unit 323.

Each of the drive circuits 311 and 321 is a three-phase (U-phase, V-phase, W-phase) inverter circuit including a plurality of switching elements such as MOSFETs. Each drive circuit 311 and 321 has three pairs of arms (single-phase half bridges) each including two FETs (Field effect transistors) connected in series between the + terminal and the-terminal of the DC power supply. It is connected in parallel to.

The current sensors 312 and 322 detect the current values I1 and I2 of the respective phases generated in the power supply path between the drive circuits 311 and 321 and the system windings 26 and 27.
The angle calculation units 313 and 323 calculate the rotation angles θm1 and θm2 indicating the rotation angle of the rotation shaft 21 of the motor 20 based on the digital values V1 and V2 output from the rotation angle sensors 52 and 53.

The first arithmetic processing unit 310 executes the periodic process for each predetermined control period, so that the torque sensor 50, the rotation angle sensor 52 (the first angle arithmetic unit 313), and the first current together with the host controller 40. Each value of the sensor 312 is captured. Then, the first arithmetic processing unit 310 generates the first PWM signal P1 through the periodic processing and performs PWM control with the first drive circuit 311 (first system winding 26) as the control target. Similarly to this, the second arithmetic processing unit 320 executes the periodic process for each predetermined control period, so that the torque sensor 51, the rotation angle sensor 53 (second angle arithmetic unit 323), And the respective values of the second current sensor 322 are fetched. Then, the second arithmetic processing unit 320 generates the second PWM signal P2 through the periodic processing, and performs PWM control with the second drive circuit 321 (second system winding 27) as the control target.

In addition, the arithmetic processing units 310 and 320 fetch mutually necessary information. Each arithmetic processing unit 310, 320 takes in a command value, a detection result of a sensor, information relating to an abnormality of the arithmetic processing unit of the other party, etc. through the arithmetic processing unit of the other party.

Next, the functions of the first arithmetic processing unit 310 and the second arithmetic processing unit 320 will be described in detail.
As illustrated in FIG. 3, each of the arithmetic processing units 310 and 320 is, for example, a micro process unit (MPU) including a single or a plurality of CPUs (Central Processing Units), and is described in “Claims”. Section”.

Each of the arithmetic processing units 310 and 320 includes a position feedback arithmetic unit (hereinafter referred to as “position F/B unit”) 410, 420, an angle conversion unit 411, 421, an assist torque arithmetic unit 412, 422, a current feedback arithmetic unit (hereinafter referred to as “current feedback arithmetic unit”). , “Current F/B section”) 413, 423, PWM output sections 414, 424, and abnormality detection sections 415, 425, respectively.

Each position F/B unit 410, 420 is a difference between each angle command value θs1*, θs2* obtained from the host controller 40 and each real angle θs1, θs2 obtained through each angle conversion unit 411, 421. The automatic steering torque components Ts1* and Ts2* are calculated based on the angle deviation. The automatic steering torque components Ts1* and Ts2* are target values of the amount of current corresponding to the automatic steering torque (power) to be generated in the motor 20 through the system windings 26 and 27. That is, the automatic steering torque components Ts1* and Ts2* are current command values.

Each of the angle conversion units 411 and 421 integrates the respective rotation angles θm1 and θm2 obtained from the angle calculation units 313 and 323, respectively, to obtain an absolute angle that is a numerical value of an angle range wider than 0 to 360°. Convert to. Then, the angle conversion units 411 and 421 calculate the actual angles θs1 and θs2 by multiplying the rotation angles θm1 and θm2 converted into the absolute angles by a coefficient. This coefficient is determined according to the rotation speed ratio between the reduction mechanism 22 and the rotation shaft 21 of the motor 20.

Note that each position F/B unit 410, 420 outputs a zero value regardless of the value of each automatic steering torque component Ts1*, Ts2* when it can determine that there is an intervention operation during the setting of the automatic steering mode. .. Similarly to this case, since the position F/B units 410 and 420 invalidate the angle command values θs1* and θs2* output by the host controller 40 during the non-setting of the automatic steering mode, the zero value is set. Output.

The assist torque calculation units 412 and 422 calculate the assist torque components Ta1* and Ta2* based on the torque values Tm1 and Tm2 obtained from the torque sensors 50 and 51. The assist torque components Ta1* and Ta2* are target values of the amount of current corresponding to the assist torque (power) to be generated in the motor 20 through the system windings 26 and 27. That is, each assist torque component Ta1*, Ta2* is a current command value.

A torque command value T1*, which is an addition value of the automatic steering torque component Ts1* calculated in the first ECU 31, and an assist torque component Ta1*, and an automatic calculation calculated in the second ECU 32 are applied to the respective current F/B units 413 and 423. Any torque command value of the torque command value T2*, which is the added value of the steering torque component Ts2* and the assist torque component Ta2*, is input. The torque command value, which is the sum of the automatic steering torque component and the assist torque component, is the current command value.

Then, each current F/B unit 413, 423, based on the torque command value of each torque command value T1*, T2*, the rotation angle and each phase current value, the duty command value D1 of the PWM control. Calculate * and D2*. The rotation angle in this case is a rotation angle obtained in each of the ECUs 31 and 32 to which each calculation unit that calculates the input torque command value belongs, while each phase current value corresponds to each current F/B unit 413. It is each phase current value obtained in each ECU 31, 32 to which 423 belongs.

Each PWM output unit 414, 424 calculates each PWM signal P1, P2 based on each duty command value D1*, D2* calculated in each ECU 31, 32 to which it belongs.
Each abnormality detection unit 415, 425 performs self-diagnosis as to whether or not there is an abnormality in which control related to operation such as power supply to each system winding 26, 27 to which current is to be supplied in each ECU 31, 32 to which it belongs cannot be continued. It has a self-diagnosis function. Each abnormality detection unit 415, 425 determines whether or not there is an abnormality in each angle command value θs1*, θs2*, each rotation angle θm1, θm2, or each torque value Tm1, Tm2 obtained in each ECU 31, 32 to which it belongs. Diagnose.

When each abnormality detection unit 415, 425 self-diagnoses that an abnormality has occurred in each of the ECUs 31, 32 to which it belongs, as a result, each abnormality detection unit FLG1, FLG2 is output. Each of the abnormality flags FLG1 and FLG2 is output to the position F/B section and the assist torque calculation section of the ECU to which it belongs. The abnormality flag FLG1 output from the abnormality detection unit 415 of the first ECU 31 is sent to the second calculation processing unit 320 (the position F/B unit 420 and the assist torque calculation unit 422) of the second ECU 32 via the interfaces com13 and com23. It is output to. As a result, the arithmetic processing units 310 and 320 (the position F/B units 410 and 420 and the assist torque arithmetic units 412 and 422) detect that an abnormality has occurred in the respective ECUs 31 and 32. The second arithmetic processing unit 320 detects that an abnormality has occurred in the first ECU 31.

In the present embodiment, when the respective ECUs 31 and 32 are normal and do not detect the occurrence of abnormality through the respective abnormality detection units 415 and 425, the respective ECUs 31 and 32 include the first ECU 31, that is, the first arithmetic processing unit. A master-slave relationship is established in which 310 is the master and the second ECU 32, that is, the second arithmetic processing unit 320 is the slave. In this case, the torque command value T1* calculated by the first calculation processing unit 310 of the master is used to calculate the PWM signals P1 and P2 of the calculation processing units 310 and 320, and the first calculation processing of the master is performed. The rotation angle θm1 detected by the rotation angle sensor 52 connected to the first ECU 31 to which the unit 310 belongs is used.

As a result, the arithmetic processing units 310 and 320 operate synchronously so as to calculate the PWM signals P1 and P2 whose phases match each other, and drive the driving circuits 311 and 321 (the system windings 26 and 27). Is basically configured to supply the same amount of current at the same timing. That is, the same torque command value and the same rotation angle are used for the calculation of the PWM signals P1 and P2 of the calculation processing units 310 and 320, and they are matched by the drive circuits 311 and 321 (the system windings 26 and 27). A torque command value calculated so that the required current amount is obtained is used. The torque command value of this embodiment is calculated as a target value of the amount of current corresponding to half (50%) of the total torque generated in the motor 20.

Specifically, as indicated by a thick line in FIG. 3, the first calculation processing unit 310 of the master calculates the automatic steering torque component Ts1* calculated by the position F/B unit 410 and the assist torque calculation unit 412. The torque command value T1*, which is the addition value with the assist torque component Ta1*, is output to the current F/B unit 413. At the same time, the first arithmetic processing unit 310 of the master outputs the torque command value T1* to the current F/B unit 423 of the second arithmetic processing unit 320 of the slave via the interfaces com13 and com23, and at the same time, rotates the rotation angle. θm1 is output to the current F/B unit 423 of the slave second arithmetic processing unit 320 via the interfaces com13 and com23.

Then, the first calculation processing unit 310 of the master uses the torque command value T1* calculated by itself and the rotation angle θm1 detected through the rotation angle sensor 52 connected to the first ECU 31 to which the first calculation processing unit 310 belongs, to generate the first drive circuit. PWM control is performed with 311 (first system winding 26) as a control target. In addition, the slave second arithmetic processing unit 320 is connected to the torque command value T1* calculated by the master first arithmetic processing unit 310 and the rotation connected to the first ECU 31 to which the master first arithmetic processing unit 310 belongs. Using the rotation angle θm1 detected by the angle sensor 52, the second drive circuit 321 (second system winding 27) is PWM-controlled as a control target.

That is, in FIG. 3, since the first calculation processing unit 310 outputs the first PWM signal P1 so that dots are added in the blocks, the position F/B unit 410, the angle conversion unit 411 (the first angle calculation unit 313). (Rotation angle sensor 52)), assist torque calculation unit 412, current F/B unit 413, and PWM output unit 414 execute various processes. Further, in the second calculation processing section 320, the current F/B section 423 and the PWM output section 424 execute various processes in order to output the second PWM signal P2.

On the other hand, in FIG. 3, it is necessary for the position F/B unit 420 and the assist torque calculation unit 422 to output the second PWM signal P2 in the second calculation processing unit 320 so that no dots are added to the blocks. Information output is disabled. In this case, the angle command value θs2* and the actual angle θs2 are input to the position F/B unit 420, but the automatic steering torque component Ts2* is not output. The torque value Tm2 is input to the assist torque calculation unit 422, but the assist torque component Ta2* is not output. The position F/B unit 420 and the assist torque calculation unit 422 may or may not actually calculate the automatic steering torque component Ts2* and the assist torque component Ta2*.

Further, in FIG. 3, in the first arithmetic processing unit 310, the abnormality detection unit 415 self-diagnoses that an abnormality has occurred in the first ECU 31 so that a dot is added in the block. In this case, the abnormality detection unit 415 performs the abnormality detection process by performing the periodic process for each control period of the first arithmetic processing unit 310.

Specifically, as shown in FIG. 4, in the abnormality detection process, the abnormality detection unit 415 of the first arithmetic processing unit 310 receives the torque value Tm1 input via the interface com11 and the torque value Tm1 input via the interface com12. The angle command value θs1* and the rotation angle θm1 obtained through the first angle calculator 313 are acquired.

Then, the abnormality detection unit 415 determines whether or not there is an abnormality in the torque value Tm1 which is the detection result of the torque sensor 50 (S10).
In S10, when the abnormality detection unit 415 determines that the torque value Tm1 which is the detection result of the torque sensor 50 has no abnormality (S10: NO), the abnormality command value θs1* input from the host control device 40 is set. It is determined whether or not there is an abnormality (S20).

In S20, when the abnormality detection unit 415 determines that the angle command value θs1* input from the host controller 40 is not abnormal (S20: NO), the rotation angle θm1 which is the detection result of the rotation angle sensor 52. It is determined whether there is an abnormality (S30).

In S30, when the abnormality detection unit 415 determines that there is no abnormality in the rotation angle θm1 which is the detection result of the rotation angle sensor 52 (S30: NO), the abnormality detection processing ends.
In S10, S20, and S30, the abnormality detection unit 415 determines whether or not the torque value Tm1, the angle command value θs1*, and the rotation angle θm1 are input in each predetermined cycle. It is determined whether or not it is appropriate based on the comparison with the previous value and the calculation of the sum of squares.

When the torque value Tm1 is not input in each predetermined cycle, there is a possibility that the interface com11 is disconnected (“x” in FIG. 5). If the torque value Tm1 is not appropriate, there is a possibility that the sensor of the torque sensor 50 is abnormal. Further, when the angle command value θs1* is not input in each predetermined cycle, there is a possibility that the interface com12 is broken (“x” in FIG. 5). If the angle command value θs1* is not appropriate, there is a possibility that the host controller 40 has a calculation error. Further, when the rotation angle θm1 is not input in each predetermined cycle, there is a possibility that the rotation angle sensor 52 or the first angle calculation unit 313 is disconnected (“x” in FIG. 5). If the rotation angle θm1 is not appropriate, there is a possibility that the rotation angle sensor 52 has a sensor abnormality and the first angle calculation unit 313 has a calculation abnormality.

Then, the abnormality detection unit 415 determines that there is an abnormality in the torque value Tm1, the angle command value θs1*, or the rotation angle θm1 (S10:YES, S20:YES, or S30:YES, in FIG. 5). "X"), and the abnormality flag FLG1 is output (S40). In S40, the abnormality detection unit 415 outputs the abnormality flag FLG1 to the position F/B unit 410 and the assist torque calculation unit 412 of the first calculation processing unit 310. Further, in this case, the abnormality detection unit 415 outputs the abnormality flag FLG1 to the position F/B unit 420 and the assist torque calculation unit 422 of the second calculation processing unit 320 via the interfaces com13 and com23. Then, the abnormality detection unit 415 ends the abnormality detection process.

In the present embodiment, after the abnormality flag FLG1 is output, the control states of the respective arithmetic processing units 310 and 320 are changed from the control state in which the first arithmetic processing unit 310 is the master and the second arithmetic processing unit 320 is the slave to The two arithmetic processing units 320 are switched to the master state, and the first arithmetic processing unit 310 is switched to the control state (master-slave switching).

In this case, the torque command value T2* calculated by the second calculation processing unit 320 of the master is used to calculate the PWM signals P1 and P2 of the calculation processing units 310 and 320, and the second calculation processing of the master is performed. The rotation angle θm2 detected by the rotation angle sensor 53 connected to the second ECU 31 to which the unit 320 belongs is used.

Specifically, in FIG. 5, the second arithmetic processing unit 320 outputs the second PWM signal P2 so that dots are added in the blocks. Therefore, the position F/B unit 420 and the angle conversion unit 421 (the second angle The calculation unit 323 (rotation angle sensor 53)), the assist torque calculation unit 422, the current F/B unit 423, and the PWM output unit 424 execute various processes. Further, in the first arithmetic processing unit 310, the current F/B unit 413 and the PWM output unit 414 execute various processes in order to output the first PWM signal P1.

On the other hand, in FIG. 5, the position F/B unit 410 of the first arithmetic processing unit 310 of the slave does not add a dot in the block, and after the abnormality flag FLG1 is input, the automatic steering torque component Ts1* Disable the output of. In addition, the assist torque calculation unit 412 of the slave first calculation processing unit 310 invalidates the output of the assist torque component Ta1* after the abnormality flag FLG1 is input. In this case, the position F/B unit 410 receives the angle command value θs1* and the actual angle θs1, but does not output the automatic steering torque component Ts1*. Further, the torque value Tm1 is input to the assist torque calculation unit 412, but the assist torque component Ta1* is not output. The position F/B unit 410 and the assist torque calculation unit 412 may or may not actually calculate the automatic steering torque component Ts1* and the assist torque component Ta1*.

Then, the second calculation processing section 320 of the master uses the torque command value T2* calculated by itself and the rotation angle θm2 detected by the rotation angle sensor 53 connected to the second ECU 32 to which the second calculation processing section 320 belongs, to drive the second drive circuit. PWM control is performed with 321 (second system winding 27) as a control target. In addition, the slave first arithmetic processing unit 310 is connected to the torque command value T2* calculated by the master second arithmetic processing unit 320, and the rotation connected to the second ECU 32 to which the master second arithmetic processing unit 320 belongs. Using the rotation angle θm2 detected by the angle sensor 53, the first drive circuit 311 (first system winding 26) is PWM-controlled as a control target.

As described above, in the present embodiment, the ECUs 31 and 32 are provided, the torque sensors 50 and 51 and the rotation angle sensors 52 and 53 that are individually connected to the ECUs 31 and 32 are provided, and the angle command values θs1*, By inputting θs2* individually, the control related to the operation of the motor 20 (the system windings 26 and 27) is made redundant.

In addition, in FIG. 5, in the second arithmetic processing unit 320, the abnormality detection unit 425 self-diagnoses that an abnormality has occurred in the second ECU 32 so that a dot is added in the block. In this case, the abnormality detection unit 425 performs the same abnormality detection process (shown in FIG. 4) as the abnormality detection unit 415 by performing the periodic process for each control period of the second arithmetic processing unit 320.

When determining that the torque value Tm2, the angle command value θs2*, or the rotation angle θm2 is abnormal, the abnormality detection unit 425 outputs the abnormality flag FLG2. The abnormality detection unit 425 outputs the abnormality flag FLG2 to the position F/B unit 420 and the assist torque calculation unit 422 of the second calculation processing unit 320.

For example, while the second arithmetic processing unit 320 is the master and the first arithmetic processing unit 310 is the slave, the position F/B unit 420 of the second arithmetic processing unit 320 receives the automatic steering torque after the abnormality flag FLG2 is input. The output of the component Ts1* is invalidated. Further, in this case, the assist torque calculation unit 422 of the second calculation processing unit 320 invalidates the output of the assist torque component Ta1* after the abnormality flag FLG2 is input. Accordingly, when it is detected that both ECUs 31 and 32 have an abnormality, the control states of the arithmetic processing units 310 and 320 are such that the second arithmetic processing unit 320 is the master and the first arithmetic processing unit 310 is the slave. The control state is switched to the control state in which the control of the operation of the motor 20 is stopped.

In some cases, the second ECU 32 may detect that the abnormality has occurred before the first ECU 31 detects that the abnormality has occurred. In this case, when it is detected that the first ECU 31 has an abnormality, the control states of the arithmetic processing units 310 and 320 are controlled such that the first arithmetic processing unit 310 is the master and the second arithmetic processing unit 320 is the slave. The state is switched to the control state in which the control of the operation of the motor 20 is stopped.

According to this embodiment described above, the following actions and effects are exhibited.
(1) When the arithmetic processing units 310 and 320 of the ECUs 31 and 32 have a master-slave relationship as in the present embodiment, the angle input from the host controller 40 to the master arithmetic processing unit. When an abnormality occurs in the command value, the torque command value (automatic steering torque component) cannot be properly calculated. However, even if the angle command value input to the master arithmetic processing unit is abnormal, the angle command value input to the slave arithmetic processing unit may not be abnormal.

In that respect, as shown in FIGS. 3 and 5, for example, when the first arithmetic processing unit 310 is a master, if an abnormality occurs in the angle command value θs1* input to the first arithmetic processing unit 310, the angle The control state is switched to use the angle command value θs2* input to the second arithmetic processing unit 320, which is a slave, instead of the command value θs1*.

In this case, even when the angle command value θs1* input from the host controller 40 to the first arithmetic processing unit 310 of the master is abnormal, the second arithmetic operation of the slave is performed instead of the angle command value θs1*. By using the angle command value θs2* input from the host controller 40 to the processing unit 320, the calculation of the torque command value can be continued. As a result, even when the first ECU 31 to which the master first arithmetic processing unit 310 belongs is abnormal, the output of the motor 20 can be maintained, and a decrease in the overall output of the motor 20 can be suppressed.

(2) In the case where the first arithmetic processing unit 310 is the master, if an abnormality occurs in the angle command value θs1* input to the first arithmetic processing unit 310, a slave is used instead of the first arithmetic processing unit 310 of the master. The second arithmetic processing unit 320 outputs the rotation angle θm2 together with the torque command value T2* to the first arithmetic processing unit 310. That is, the control states of the arithmetic processing units 310 and 320 are the control state in which the first arithmetic processing unit 310 is the master and the second arithmetic processing unit 320 is the slave, and the second arithmetic processing unit 320 is the master and the first arithmetic processing is the first arithmetic processing. It is switched to a control state in which the unit 310 is a slave.

Specifically, as shown by the thick line in FIG. 5, the position F/B unit 420 of the second calculation processing unit 320 of the master receives the angle command value θs2* and the actual angle θs2 after the abnormality flag FLG1 is input. Using and, the automatic steering torque component Ts2* is calculated. Similarly, the assist torque calculator 422 calculates the assist torque component Ta2* by using the torque value Tm2 after the abnormality flag FLG1 is input. Then, the second calculation processing unit 320 has a torque command value T2 that is the sum of the automatic steering torque component Ts2* calculated by the position F/B unit 420 and the assist torque component Ta2* calculated by the assist torque calculation unit 422. * Is output to the current F/B unit 423. At the same time, the second arithmetic processing unit 320 of the master outputs the torque command value T2* to the current F/B unit 413 of the first arithmetic processing unit 310 of the slave via the interfaces com13 and com23, and at the same time, rotates the rotation angle. θm2 is output to the current F/B unit 413 of the slave first arithmetic processing unit 310 via the interfaces com13 and com23.

As described above, according to the present embodiment, when the angle command value θs2* input to the second calculation processing unit 320 is used instead of the angle command value θs1* input to the first calculation processing unit 310, each calculation is performed. As for information transfer between the processing units 310 and 320, it is not necessary to move information back and forth between the arithmetic processing units 310 and 320.

As a result, while the respective arithmetic processing units 310 and 320 perform the periodic processing, after the abnormality occurs in the angle command value θs1* input to the first arithmetic processing unit 310, the first arithmetic processing unit 310 performs the periodic processing. The rotation angle θm2 as well as the torque command value T2* can be obtained from the second arithmetic processing unit 320 within the same cycle of the processing. Therefore, even when the first ECU 31 to which the master first arithmetic processing unit 310 belongs is abnormal, the output of the motor 20 can be appropriately controlled.

(3) In addition, when the first arithmetic processing unit 310 is a master and an abnormality occurs in the angle command value θs1* input to the first arithmetic processing unit 310, the second arithmetic operation is performed using the interfaces com13 and com23. The rotation angle θm2 is output from the processing unit 320 to the first arithmetic processing unit 310 together with the torque command value T2*. As a result, when the first ECU 31 to which the master first arithmetic processing unit 310 belongs is abnormal, even if the reduction of the overall output of the motor 20 is suppressed, the range of hardware changes such as the addition of an interface (communication line) is reduced. Can be made smaller.

(4) When the first arithmetic processing unit 310 is a master, when the angle command value θs1* has an abnormality, the first arithmetic processing unit 310 sets an abnormality flag FLG1 indicating that the abnormality has occurred, The rotation angle is transmitted and received together with the torque command value using the common interfaces com13 and com23. Thus, when the first ECU 31 to which the master first arithmetic processing unit 310 belongs is abnormal, even if the reduction of the entire output of the motor 20 is suppressed, the hardware (such as adding an interface (communication line connected to this)) The range of change can be reduced more preferably.

(5) According to the present embodiment, as described above, when the first arithmetic processing unit 310 is the master, the entire output of the motor 20 is generated even when the first ECU 31 to which the first arithmetic processing unit 310 belongs is abnormal. The motor control device 30 capable of stabilizing the application of the power applied to the steering mechanism 2 is realized by suppressing the decrease of Then, in the vehicle steering system 1 of the present embodiment realized by using the motor control device 30, it is possible to improve the reliability of applying power to the steering mechanism 2.

In addition, the above-mentioned embodiment can also be implemented in the following forms.
The detection of whether or not an abnormality has occurred in each of the ECUs 31 and 32 may be configured to be collectively detected by either of the arithmetic processing units 310 and 320. The abnormality flag FLG1 output from the abnormality detection unit 415 of the first ECU 31 is output to the second ECU 32 (second arithmetic processing unit 320) via a dedicated interface (communication line) different from the interfaces com13 and com23. You may do it. Even in these cases, it is possible to suppress a decrease in the overall output of the motor 20 when the first ECU 31 to which the master first arithmetic processing unit 310 belongs is abnormal.

-Each ECU 31 and 32 should just be connected in the motor control device 30 so that information can be transmitted and received mutually, and the concrete composition may be changed. For example, the communication of information from the first ECU 31 to the second ECU 32 and the communication of information from the second ECU 32 to the first ECU 31 may be configured to be able to be transmitted and received via dedicated interfaces (communication lines).

-For example, when the 1st arithmetic processing part 310 is a master, you may make it use the information acquired by the 2nd arithmetic processing part 320 only about the information in which abnormality has occurred. That is, when the torque value Tm1 is abnormal, in the calculation of the PWM signals P1 and P2 of the calculation processing units 310 and 320, the torque value Tm2 obtained by the second calculation processing unit 320 instead of the torque value Tm1. May be used. When the angle command value θs1* is abnormal, the second command processing unit 320 obtains the angle command value θs1* instead of the angle command value θs1* in the calculation of the PWM signals P1 and P2 of the calculation processing units 310 and 320. The angle command value θs2* may be used. Further, when the rotation angle θm1 is abnormal, in the calculation of the PWM signals P1 and P2 of the calculation processing units 310 and 320, the rotation angle θm2 obtained by the second calculation processing unit 320 instead of the rotation angle θm1. May be used. In these cases, even if an abnormality occurs in the torque value Tm1, the angle command value θs1*, or the rotation angle θm1, the relationship in which the first arithmetic processing unit 310 is the master and the second arithmetic processing unit 320 is the slave is maintained. You can Even in this case, when the first ECU 31 to which the master first arithmetic processing unit 310 belongs is abnormal, it is possible to suppress a decrease in the overall output of the motor 20.

In the motor control device 30 of the present embodiment, it is sufficient that the angle command values θs1*, θs2* input from the host control device 40 are at least redundant, the detection results of the torque sensors 50, 51, and The detection results of the rotation angle sensors 52 and 53 may not be redundant.

When the first ECU 31 is abnormal, the motor 20 may be generated with some torque through the first drive circuit 311 (first system winding 26). In this case, compared with the case where the supply of the current from the first drive circuit 311 to the first system winding 26 is cut off, it is possible to suppress a decrease in the overall output of the motor 20.

The motor control device 30 only needs to have a plurality of control systems (ECUs), and may have three or four or more control systems. In this case, the number of arithmetic processing units (driving circuits, etc.) is increased according to the number of control systems, and the torque value, the angle command value, and the rotation angle are individually input to each of the control systems. It suffices that any control system is configured to control the operation of the motor 20 as a master.

In the control of the motor 20, the steering angle that is the rotation angle of the column shaft 11a, the pinion angle that is the rotation angle of the pinion shaft 11c, or the moving position of the rack shaft 12 may be used as the actual angle θs. .. In these cases, the torque values Tm1 and Tm2 can also be calculated by processing the steering angle and the like. Thereby, the torque sensors 50 and 51 can be omitted, and the number of parts and the cost can be reduced.

The vehicle steering system 1 may be configured to switch from the automatic steering control to the assist control when an intervention operation is performed while the setting of the automatic steering mode is instructed.
The host controller 40 may output the angle deviation to the motor controller 30 instead of the angle command values θs1* and θs2*. In this case, the host controller 40 may calculate the angle deviation based on the rotation angles θm1 and θm2 obtained from the rotation angle sensors 52 and 53, the steering angle, and the like.

The calculation of each assist torque component Ta1*, Ta2* may use at least the torque values Tm1, Tm2, and the vehicle speed of the vehicle A may be used. In addition, each of the assist torque components Ta1* and Ta2* may be calculated using the torque values Tm1 and Tm2, the vehicle speed, and other factors. The automatic steering torque components Ts1* and Ts2* may be calculated by using at least the angle command values θs1* and θs2* calculated based on the vehicle surrounding environment (angle information θv). You may make it use (theta)s1*, (theta)s2* and a vehicle speed and other elements.

The vehicle steering system 1 may be, for example, one that builds a skid prevention device (vehicle stability control) as another function for supporting the traveling of the vehicle, or a lane departure prevention support system, It may be constructed together with the skid prevention device.

In the above embodiment, the vehicle steering system 1 is embodied as a type that applies power to the column shaft 11a, but may be applied to a type that applies power to the rack shaft 12. In this case, the torque sensors 50 and 51 may be provided on the pinion shaft 11c, for example.

-In the said embodiment, although the motor 20 of the vehicle steering system 1 was controlled, it is not restricted to this. For example, a steer-by-wire steering device motor, a rear wheel steering device, or a four-wheel steering device (4WS) motor may be controlled. Further, in the above-described embodiment, the motor of the steering device that executes only the assist control for assisting the steering operation may be the control target without executing the automatic steering control. Further, in the above-described embodiment, a motor mounted other than the vehicle may be a control target.

Each modification may be applied in combination with each other. For example, embodying a steer-by-wire type steering device and the configurations of other modifications may be applied in combination with each other.

DESCRIPTION OF SYMBOLS 1... Vehicle steering system, 2... Steering mechanism, 3... Actuator, 15... Steering wheel, 20... Motor, 21... Rotating shaft, 23... Rotor, 24... Stator, 25... Winding, 26... 1st system winding , 27... Second system winding, 30... Motor control device, 31... First ECU, 32... Second ECU, 40... Upper control device, 50, 51... Torque sensor, 52, 53... Rotation angle sensor, 310... First Arithmetic processing section 311, 1st drive circuit, 312 ... 1st current sensor, 313 ... 1st angle calculation section, 320 ... 2nd arithmetic processing section, 321 ... 2nd drive circuit, 322 ... 2nd current sensor, 323 ... Second angle calculator, 415, 425... Abnormality detector, Tm... Torque value, θm1, θm2... Rotation angle, θs1*, θs2*... Angle command value, T1*, T2*... Torque command value, Ta1*, Ta2 *... Assist torque component, Ts1*, Ts2*... Automatic steering torque component, FLG1... Abnormality flag, com11, com12, com13, com21, com22, com23... Interface.

Claims (5)

Each control system is provided with a plurality of control systems for controlling the operation of a motor having a plurality of windings, and each control system is provided in combination with each drive circuit so as to supply a current to each winding of each system. In the motor control device in which each external command value is input from the outside to each arithmetic unit of each control system, and a master-slave relationship is established,
The master arithmetic unit calculates a current command value that is a target of the amount of current supplied to the winding using the external command value, and outputs the current command value to the slave arithmetic unit,
The master arithmetic unit and the slave arithmetic unit are configured to respectively control the operation of the drive circuit of the control system to which they belong, based on the current command value.
When an abnormality occurs in the external command value externally input to the master arithmetic unit, the external command value externally input to the slave arithmetic unit instead of the external command value is the current command value A motor control device configured to be used for calculation. When an abnormality occurs in the external command value externally input to the master arithmetic unit, the slave arithmetic unit uses the external command value externally input instead of the master arithmetic unit, The motor control device according to claim 1, wherein the motor control device is configured to calculate a current command value and output the current command value to the calculation unit of the master. The operation unit of the master and the operation unit of the slave are in a state in which information can be output from the operation unit of the master to the operation unit of the slave and the operation unit of the slave with respect to the operation unit of the master. Connected via an interface having a state that enables output of information,
The interface sets a state in which information can be output from the master computing unit to the slave computing unit when no abnormality occurs in the external command value input from the outside to the master computing unit. On the other hand, when an abnormality occurs in the external command value input to the arithmetic unit of the master from the outside, the slave arithmetic unit is configured to output information to the arithmetic unit of the master. The motor control device according to claim 2, which is provided. The calculation unit of the master has an abnormality detection unit that detects an abnormality in the external command value input from the outside,
The abnormality detection unit is configured to output information indicating that the abnormality has occurred through the interface when an abnormality has occurred in the external command value input to the calculation unit of the master from the outside. The motor control device according to claim 3. A motor having windings of a plurality of systems for giving power for steering the steered wheels of the vehicle,
The motor control device according to claim 1, wherein the motor is a control target.
Steering device equipped with.

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