Control device for an electric machine

Abstract

A control device (50; 100) for an electric motor (21) includes an electronic control unit. The electronic control unit includes a first controller (81), a second controller (83), a third controller (84), and a fourth controller (85). The first controller (81) is configured to calculate a feedback control torque to be generated by the electric motor (21) through execution of feedback control. The second controller (83) is configured to calculate a disturbance torque based on the feedback control torque and a predetermined angle. The third controller (84) is configured to correct the feedback control torque by using the disturbance torque. The fourth controller (85) is configured to compensate for a transfer time lag between the feedback control torque and the predetermined angle to the second controller (83).

Description

TECHNICAL FIELD

[0001] The present application relates to a control device for a motor. BACKGROUND

[0002] A control device that controls electric power supplied to a motor for controlling an automatic driving system, a driving support system, or a steering system such as a steer-by-wire system is known. For example, the control device of Japanese Unexamined Patent Application Publication No. 2018-183046 (JP 2018-183046 A) calculates a target motor torque (target automatic steering torque) based on a target steering angle set by a control device for automatic driving control, and calculates a target motor current by dividing the calculated target motor torque by a torque constant of the motor. The control device for the motor feeds back the current supplied to the motor so that the motor current detected by a current detection circuit coincides with the target motor current. SUMMARY

[0003] The control device of JP 2018-183046 A includes a disturbance observer. The disturbance observer estimates a disturbance torque based on a rotor rotation angle of the motor detected by a rotation angle sensor and the target motor torque calculated based on the target steering angle. The control device calculates the target motor torque taking into account the disturbance torque calculated by the disturbance observer. Higher accuracy of the motor control is achieved by compensating for the disturbance torque.

[0004] However, the rotor rotation angle of the motor detected by the rotation angle sensor is delayed by a delay time of the rotation angle sensor or a dead time in the steering mechanism compared to the target motor torque. The delay time is a time from when the rotation angle sensor detects the rotor rotation angle to when the rotation angle sensor fixes the rotor rotation angle as a sensor output. The dead time is a time during which there is no response even when an operation is performed on the motor, for example. There is a concern about a decrease in accuracy of calculating the disturbance torque due to a time difference between the two inputs to the disturbance observer.

[0005] The present application improves the accuracy of calculating the disturbance torque.

[0006] An aspect of the present application provides a control device for an electric motor. The electric motor rotates a steered wheel of a vehicle. The control device includes an electronic control unit. The electronic control unit includes: a first controller, a second controller, a third controller, and a fourth controller. The first controller is configured to calculate a feedback control torque to be generated by the electric motor through execution of feedback control. The feedback control is control to cause an angle that can be converted into a wheel steering angle of the steered wheel to follow a target angle. The second controller is configured to calculate a disturbance torque based on a predetermined angle and the feedback control torque calculated by the first controller. The predetermined angle is an angle that can be converted into the wheel steering angle and is detected by a sensor. The disturbance torque is a torque that affects the angle that can be converted into the wheel steering angle, other than the torque to be generated by the electric motor. The third controller is configured to correct the feedback control torque calculated by the first controller by using the disturbance torque calculated by the second controller. The fourth controller is configured to compensate for a transfer time lag between the predetermined angle to the second controller and the feedback control torque calculated by the first controller.

[0007] With the above configuration, the transfer time lag between the feedback control torque calculated by the first controller to the second controller and the angle that can be converted into the wheel steering angle and is detected by the sensor is compensated for. Therefore, the accuracy of calculating the disturbance torque by the second controller is further improved. In addition, the disturbance torque is further appropriately compensated for, and thus the electric motor is controlled with high accuracy.

[0008] In the control device, the fourth controller can be configured to delay the feedback control torque calculated by the first controller (81) by a delay of the predetermined angle with respect to the feedback control torque calculated by the first controller.

[0009] With the above configuration, the transfer time lag between the feedback control torque calculated by the first controller to the second controller and the angle that can be converted into the wheel steering angle and is detected by the sensor is eliminated. Therefore, the accuracy of calculating the disturbance torque by the second controller is further improved.

[0010] In the control device, the electronic control unit can further include a fifth controller configured to calculate a feedforward control torque based on a second-order time derivative of the target angle. The third controller can be configured to subtract the disturbance torque from a value obtained by adding the feedforward control torque to the feedback control torque calculated by the first controller.

[0011] With the above configuration, the response of the electric motor control is further improved by using the feedforward control torque, as compared with a case where the electric motor is controlled without using the feedforward control torque.

[0012] With the above configuration, the accuracy of calculating the disturbance torque is further increased. Attached Figure Description

[0013] The features, advantages, and technical and industrial significance of exemplary embodiments of the present invention will now be described with reference to the accompanying drawings, wherein like reference numerals denote like elements, and in the drawings:

[0014] Figure 1 This is a configuration diagram of an electric power steering system equipped with a control device for a motor according to the first embodiment;

[0015] Figure 2 This is a control block diagram of a control device for an electric motor according to the first embodiment;

[0016] Figure 3 This is a control block diagram of the instruction value calculation unit in the first embodiment;

[0017] Figure 4 This is a control block diagram of the steering angle feedback control unit in the first embodiment;

[0018] Figure 5 This is a configuration diagram of a steering device for a motor, in which a control device for a motor according to the second embodiment is installed; and

[0019] Figure 6 This is a control block diagram of a control device for an electric motor according to the second embodiment. Detailed Implementation

[0020] In the following text, a first embodiment in which the control device for the motor is implemented as a control device for electric power steering (EPS) will be described. Figure 1 As shown, the EPS 10 includes a steering shaft, a pinion shaft 14, and a wheel steering shaft 15, which serve as the power transmission path between the steering wheel 11 and the steering wheel 12. The wheel steering shaft 15 is located along the vehicle width direction ( Figure 1 Extending in the left and right directions. Steering wheels 12 are coupled to the two ends of wheel steering shaft 15 via tie rods 16. Pinion shaft 14 is configured to intersect wheel steering shaft 15. The pinion teeth 14a of pinion shaft 14 mesh with the rack teeth 15a of wheel steering shaft 15. Wheel steering shaft 15 moves linearly with the rotation of steering wheel 11. The linear movement of wheel steering shaft 15 is transmitted to right steering wheel 12 and left steering wheel 12 via tie rods 16, thus changing the wheel steering angle θ of steering wheels 12. w .

[0021] The EPS 10 includes a motor 21 and a reduction mechanism 22 as components for generating an assist force that is a force for assisting the driver in steering. The motor 21 functions as an assist motor that is a source for generating the assist force. For example, a three-phase brushless motor is employed as the motor 21. The motor 21 is coupled to a pinion shaft 23 via the reduction mechanism 22. Pinion teeth 23a of the pinion shaft 23 are engaged with rack teeth 15a of the wheel steering shaft 15. Rotation of the motor 21 is reduced in speed by the reduction mechanism 22, and the rotation force that is reduced in speed is transmitted to the wheel steering shaft 15 via the pinion shaft 23 as the assist force. The wheel steering shaft 15 moves in the vehicle width direction along with the rotation of the motor 21.

[0022] The EPS 10 includes a control device 50. The control device 50 controls the motor 21 on the basis of results detected by various sensors. The sensors include a torque sensor 51, a vehicle speed sensor 52, and a rotation angle sensor 53. The torque sensor 51 detects a steering torque T h that acts on the steering shaft 13 by a rotation operation of the steering wheel 11. The vehicle speed sensor 52 detects a vehicle speed V. The rotation angle sensor 53 is provided in the motor 21. The rotation angle sensor 53 detects a rotation angle Θ m of the motor 21. The control device 50 performs assist control by energization control of the motor 21 to generate an assist force in accordance with the steering torque T h . The control device 50 controls electric power supplied to the motor 21 on the basis of the steering torque T h detected by the torque sensor 51, the vehicle speed V detected by the vehicle speed sensor 52, and the rotation angle Θ m detected by the rotation angle sensor 53.

[0023] Next, the control device 50 will be described in detail. As shown in Figure 2 , the control device 50 includes a pinion angle calculation unit 61, an instruction value calculation unit 62, and an energization control unit 63.

[0024] The pinion angle calculation unit 61 calculates a pinion angle Θ p on the basis of the rotation angle Θ m of the motor 21 detected by the rotation angle sensor 53. The pinion angle Θ p is a rotation angle of the pinion shaft 23. The pinion angle calculation unit 61 calculates the pinion angle Θ m by, for example, dividing the rotation angle Θ p of the motor 21 by a reduction ratio of the reduction mechanism 22.

[0025] The pinion angle calculation unit 61 can calculate a rotation angle of the pinion shaft 14 as the pinion angle Θ pIn this case, the pinion angle calculation unit 61 calculates a pinion angle θ p , for example, by dividing the rotation angle θ m of the motor 21 by the reduction ratio of the components from the motor 21 to the pinion shaft 14.

[0026] The command value calculation unit 62 calculates an assist command value T* based on the steering torque T h detected by the torque sensor 51 and the vehicle speed V detected by the vehicle speed sensor 52. The assist command value T* indicates an assist torque that is a rotational force to be generated by the motor 21. The command value calculation unit 62 calculates the assist command value T* that has a larger absolute value as the absolute value of the steering torque T h increases or that has a larger absolute value as the vehicle speed V decreases.

[0027] The energization control unit 63 supplies electric power to the motor 21 in accordance with the assist command value T*. Specifically, the energization control unit 63 is configured as follows. The energization control unit 63 calculates a current command value based on the assist command value T*. The current command value is a target value of the current to be supplied to the motor 21. The energization control unit 63 detects the current I m supplied to the motor 21 by a current sensor 64 provided in the electric power supply line to the motor 21. The energization control unit 63 calculates a deviation between the current command value and the actual value I m of the current, and controls the electric power supplied to the motor 21 so that the deviation is minimized (feedback control of the current I m ). Thus, the motor 21 generates a torque in accordance with the assist command value T*.

[0028] Next, the command value calculation unit 62 will be described in detail. As Figure 3 shown, the command value calculation unit 62 includes an adder 70, a target steering torque calculation unit 71, a torque feedback control unit 72, a target angle calculation unit 73, an angle feedback control unit 74, and an adder 75.

[0029] The adder 70 calculates an input torque T in * as a torque to be applied to the steering shaft 13 by adding the steering torque T h detected by the torque sensor 51 and a first assist torque T1* calculated by the torque feedback control unit 72.

[0030] The target steering torque calculation unit 71 calculates a target steering torque T in * based on the input torque T h * calculated by the adder 70. The target steering torque T h* is the steering torque T applied to the steering wheel 11. h The target value. Target steering torque calculation unit 71 calculates the target steering torque T. h * The target steering torque T h *With input torque T in The absolute value of * increases and thus has a larger absolute value.

[0031] The torque feedback control unit 72 acquires the steering torque T detected by the torque sensor 51. h And the target steering torque T calculated by the target steering torque calculation unit 71 h *. The torque feedback control unit 72 controls the steering torque T. h Execute feedback control to adjust the steering torque T detected by torque sensor 51. h Follow the target steering torque T h *To calculate the first auxiliary torque T1*.

[0032] The target angle calculation unit 73 acquires the steering torque T detected by the torque sensor 51. h The first auxiliary torque T1* calculated by the torque feedback control unit 72 and the vehicle speed V detected by the vehicle speed sensor 52. The target angle calculation unit 73 calculates the target angle based on the acquired steering torque T1*. h The target pinion angle θ is calculated using the first auxiliary torque T1* and the vehicle speed V. p * Target pinion angle θ p * represents the target value of the rotation angle of the pinion shaft 23.

[0033] The angle feedback control unit 74 acquires the target pinion angle θ calculated by the target angle calculation unit 73. p *and the actual pinion angle θ calculated by the pinion angle calculation unit 61 p The angle feedback control unit 74 measures the angle θ of the pinion gear. p Execute feedback control to adjust the actual pinion angle θ p Following the target pinion angle θ p *To calculate the second auxiliary torque T2*.

[0034] The adder 75 calculates the auxiliary command value T* by adding the first auxiliary torque T1* calculated by the torque feedback control unit 72 and the second auxiliary torque T2* calculated by the angle feedback control unit 74. When current based on the auxiliary command value T* is supplied to the motor 21, the motor 21 generates torque according to the auxiliary command value T*.

[0035] Next, the angle feedback control unit 74 will be described in detail. For example... Figure 4As shown, the angle feedback control unit 74 includes: a feedback control unit 81, a feedforward control unit 82, a disturbance observer 83, and an adder 84.

[0036] The feedback control unit 81 is configured to make the pinion angle estimate θ pe Approximately to the target pinion angle θ p *. Estimated angle θ of the pinion pe The pinion angle θ is calculated by the disturbance observer 83. p The estimated value. The feedback control unit 81 includes a subtractor 81A and a PD control unit (proportional-derivative control unit) 81B. The subtractor 81A calculates the target pinion angle θ. p *Compared with the pinion angle estimate θ calculated by disturbance observer 83 pe The deviation Δθ between p (=θ p *-θ pe The PD control unit 81B measures the deviation Δθ calculated by the subtractor 81A. p Perform proportional-derivative operations to calculate the feedback control torque T. fb In other words, the feedback control torque T fb It is for the deviation Δθ p The sum of the output values ​​of the proportional control element and the derivative control element.

[0037] The feedforward control unit 82 is configured to improve the control response by compensating for the response delay caused by the inertia of the EPS 10. The feedforward control unit 82 includes an angular acceleration calculation unit 82A and a multiplication unit 82B. The angular acceleration calculation unit 82A evaluates the target pinion angle θ. p The second derivative of * is used to calculate the acceleration α of the target pinion (=d). 2 θ p / dt 2 The multiplication unit 82B calculates the feedforward control torque T by multiplying the inertia J of EPS 10 by the target pinion angular acceleration α calculated by the angular acceleration calculation unit 82A. ff (=J·α) is used as the inertia compensation value. For example, the inertia J is obtained according to the physical model of EPS 10.

[0038] The disturbance observer 83 is configured to estimate and compensate for disturbance torque. Disturbance torque is a nonlinear torque generated as a disturbance in the device to be controlled (EPS10), and it affects the pinion angle θ. p The torque, not the torque generated by motor 21. Disturbance observer 83 is based on the second auxiliary torque T2* and the actual pinion angle θ. p To calculate the estimated disturbance torque T, which serves as the disturbance torque compensation value.1d and pinion angle estimation value θ pe . The second assist torque T2* is a target value of the device. The actual pinion angle θ p is an output of the device. The disturbance observer 83 can be configured to calculate a disturbance torque estimation value T 1d and pinion angle estimation value θ pe .

[0039] The adder 84 calculates the second assist torque T2* (= T ff + T fb - T 1d ) by subtracting the disturbance torque estimation value T fb from a value obtained by adding the feedforward control torque T ff and the feedback control torque T ld . Thus, the second assist torque T2* that compensates for the inertia and the disturbance torque is obtained. Using the assist command value T* based on the second assist torque T2*, thus further higher accuracy motor control is performed.

[0040] The pinion angle θ m is calculated based on the rotation angle θ p of the motor 21 detected by the rotation angle sensor 53. Thus, the pinion angle θ p may delay a delay time of the rotation angle sensor 53 or a dead time in the EPS 10 compared to the assist command value T*. The delay time of the rotation angle sensor 53 is a time from when the rotation angle sensor 53 detects the rotation angle θ m to when the rotation angle sensor 53 fixes the rotation angle θ m as a sensor output. The dead time in the EPS 10 is a time during which there is no response even when an operation is performed on the motor 21. Then, there is a concern about a decrease in accuracy of calculating the disturbance torque estimation value T 1d due to a time difference between the two inputs (i.e., the assist command value T* and the pinion angle θ p ) to the disturbance observer 83.

[0041] In the present embodiment, the angle feedback control unit 74 includes a delay processing unit 85. The delay processing unit 85 is provided to minimize the time difference between the two inputs to the disturbance observer 83. The delay processing unit 85 delays the second assist torque T2* by a determined delay time. The second assist torque T2* is one of the two inputs to the disturbance observer 83. The set time is set based on the dead time of the device and the delay time of the rotation angle sensor 53. More specifically, the pinion angle θ pHow long is the second assist torque T2* delayed with respect to the second assist torque T2*, and the delay time of the second assist torque T2* is set with respect to the measured time.

[0042] For example, when the pinion angle θ p The delay processing unit 85 delays the second assist torque T2* by one calculation cycle of the second assist torque T2* when the second assist torque T2* is delayed by one calculation cycle. The delay processing unit 85 acquires the second assist torque T2* calculated by the adder 84, and holds the acquired second assist torque T2*. The adder 84 calculates the second assist torque T2* at a predetermined calculation cycle. The second assist torque T2* held in the delay processing unit 85 is updated every time the second assist torque T2* is calculated by the adder 84. In other words, the second assist torque T2* held in the delay processing unit 85 is the last value of the second assist torque T2* (the second assist torque T2* one cycle ago). The second assist torque T2* is the current value calculated by the adder 84.

[0043] In this way, by delaying the second assist torque T2* for a certain time, the pinion angle θ p The pinion angle θ p The time lag between the second assist torque T2*.

[0044] Advantages of the first embodiment

[0045] According to the first embodiment, the following advantageous effects are obtained. (1) The pinion angle θ p The time lag between the second assist torque T2*.

[0046] Second embodiment

[0047] Next, a second embodiment in which the control device for the motor is applied to a steer-by-wire steering device will be described. The same reference numerals denote the same components as those of the first embodiment, and detailed description thereof will be omitted.

[0048] As Figure 5As shown, in the steering system 90 for a vehicle, the steering shaft 13 and the pinion shaft 14 are mechanically separated. The steering system 90 includes a reaction motor 91 and a reduction gear 92 as components for generating steering reaction force. The steering reaction force is a force acting in the opposite direction to the direction in which the driver operates the steering wheel 11. By applying the steering reaction force to the steering wheel 11, an appropriate sense of resistance can be provided to the driver.

[0049] The reaction motor 91 is the source of the steering reaction force. For example, a three-phase brushless motor is used as the reaction motor 91. The rotation shaft of the reaction motor 91 is coupled to the steering shaft 13 via a reduction gear 92. The torque of the reaction motor 91 is applied to the steering shaft 13 as the steering reaction force. A rotation angle sensor 93 is provided in the reaction motor 91. The rotation angle sensor 93 detects the rotation angle θ of the reaction motor 91. mr .

[0050] Torque sensor 51 is located on a portion of steering shaft 13 between reduction gear 92 and steering wheel 11. Motor 21 serves as a wheel steering motor, acting as a source for generating wheel steering force. Wheel steering force is the driving force used to rotate steering wheel 12.

[0051] Next, the control device 100 of the steering device 90 will be described in detail. For example... Figure 6 As shown, the control device 100 includes: a steering angle calculation unit 101, a command value calculation unit 102, and a power control unit 103.

[0052] The steering angle calculation unit 101 is based on the rotation angle θ of the reaction motor 91 detected by the rotation angle sensor 93. mr To calculate the steering angle θ s Steering angle θ s This refers to the rotation angle of the steering wheel 11. The command value calculation unit 102 is based on the steering torque T. h Vehicle speed V and steering angle θ s To calculate the steering reaction force command value T r * The command value calculation unit 102 calculates the steering reaction force command value T. r * The steering reaction force command value T r *With steering torque T h The absolute value increases with the increase of the absolute value, or decreases with the decrease of vehicle speed V. The command value calculation unit 102 calculates the steering reaction force command value T. r During the process, the target steering angle θ of steering wheel 11 is calculated. s *

[0053] The power control unit 103 operates according to the steering reaction force command value T. r* The reaction motor 91 is supplied with electric power. Specifically, the energization control unit 103 calculates a current command value for the reaction motor 91 based on the steering reaction force command value T r * The energization control unit 103 detects the current I mr in the electric power supply line for the reaction motor 91 with the current sensor 104 provided in the electric power supply line. The energization control unit 103 finds a deviation between the current command value and the actual value I mr of the current, and controls the electric power supplied to the reaction motor 91 so that the deviation is minimized. Thus, the reaction motor 91 generates a torque in accordance with the steering reaction force command value T r *.

[0054] The control device 100 includes an angle feedback control unit 105 in addition to the pinion angle calculation unit 61 and the energization control unit 63. The angle feedback control unit 105 has a processing function similar to that of the angle feedback control unit 74 of the first embodiment described with reference to Figure 4 The angle feedback control unit 105 acquires the target steering angle θ s * calculated by the command value calculation unit 102 as a target pinion angle θ p *. The angle feedback control unit 105 acquires the pinion angle θ p calculated by the pinion angle calculation unit 61. The angle feedback control unit 105 calculates a pinion angle command value T p * by feedback control of the pinion angle θ p so that the actual pinion angle θ p follows the target pinion angle θ s * (here, equal to the target steering angle θ p *). The energization control unit 63 supplies electric power to the wheel steering motor 21 in accordance with the pinion angle command value T p *. Thus, the wheel steering motor 21 rotates by a certain angle in accordance with the pinion angle command value T p *.

[0055] Next, the command value calculation unit 102 will be described in detail. As shown by the reference numerals in parentheses in Figure 3 , the command value calculation unit 102 basically has a processing function similar to that of the command value calculation unit 62 of the first embodiment. However, the command value calculation unit 102 differs from the command value calculation unit 62 in the following points.

[0056] The torque feedback control unit 72 acquires the steering torque T h detected by the torque sensor 51 and the target steering torque T h*. The torque feedback control unit 72 controls the steering torque T. h Feedback control to make the steering torque T h Follow the target steering torque T h * to calculate the first steering reaction force command value T r1 *

[0057] The target angle calculation unit 73 acquires the steering torque T detected by the torque sensor 51. h The first steering reaction force command value T calculated by the torque feedback control unit 72 r1 *And the vehicle speed V detected by vehicle speed sensor 52. Target angle calculation unit 73 is based on steering torque T. h First steering reaction force command value T r1 *The target steering angle θ of the steering wheel 11 is calculated using the vehicle speed V. s *

[0058] The angle feedback control unit 74 acquires the steering angle θ calculated by the steering angle calculation unit 101. s And the target turning angle θ calculated by the target angle calculation unit 73 s *. The angle feedback control unit 74 uses the steering angle θ calculated by the steering angle calculation unit 101 to... s Feedback control to make the steering angle θ s Follow the target turning angle θ s * to calculate the second steering reaction force command value T r2 *

[0059] Adder 75 inputs the first steering reaction force command value T calculated by torque feedback control unit 72. r1 * and the second steering reaction force command value T calculated by the angle feedback control unit 74. r2 *Add them together to calculate the steering reaction force command value T. r *

[0060] Advantages of the second embodiment

[0061] According to the second embodiment, the following beneficial effects are obtained: (2) The steering angle θ in the disturbance observer 83, which is input to the angle feedback control unit 74, is eliminated. s With the second steering reaction force command value T r2 The propagation delay between * is eliminated. The pinion angle θ of the disturbance observer 83 input to the angle feedback control unit 105 is eliminated. p With the second steering reaction force command value T r2a time lag between the two. Thus, the accuracy of the disturbance torque calculated by the disturbance observer 83 is further improved. In addition, the disturbance torque is further appropriately compensated, and thus the reaction motor 91 and the motor 21 serving as a wheel steering motor are controlled with higher accuracy.

[0062] Other Embodiments

[0063] The first embodiment and the second embodiment can be modified as follows. In the first embodiment, an example in which the control device 50 is applied to an EPS 10 that applies an assist force to the wheel steering shaft 15 is described. Alternatively, the control device 50 can be applied to an EPS that applies an assist force to the steering shaft 13. As described above, the control device 50 can be applied to an EPS that applies an assist force to the steering shaft 13 or the wheel steering shaft 15. Figure 1 The motor 21 is coupled to the steering shaft 13, for example, via a reduction mechanism 22, as indicated by long and two short dotted lines alternated in

[0064] In the second embodiment, a clutch can be provided in the steering device 90. In this case, the steering shaft 13 and the pinion shaft 14 are coupled via the clutch 94, as indicated by long and two short dotted lines alternated in Figure 5 The electromagnetic clutch that provides power or interrupts power by supplying current to the field coil or interrupting current to the field coil is employed as the clutch 94. The control device 100 performs engagement / detachment control for engaging or detaching the clutch 94. When the clutch 94 is detached, the power transmission between each of the steering wheels 12 and the steering wheel 11 is mechanically interrupted. When the clutch 94 is engaged, the power transmission between each of the steering wheels 12 and the steering wheel 11 is mechanically allowed.

[0065] In the first embodiment and the second embodiment, when the disturbance observer 83 uses an integral operation in calculating the pinion angle estimate value θ pe In this case, for the discrete integral operation, a bilinear transformation relationship can be used.

[0066] The vehicle can be equipped with an automatic driving system that implements various driving support functions to further improve the safety or convenience of the vehicle or an automatic driving function that utilizes the system to take over the driving operation. In this case, the vehicle is equipped with a host control device 500 of a control device that generally controls various onboard systems, as indicated by long and two short dotted lines alternated in Figure 1 and Figure 5 The host control device 500 determines the optimal control method based on the state of the vehicle at any given time, and the host control device 500 instructs various onboard control devices to perform control in accordance with the determined control method, respectively.

[0067] The host control device 500 intervenes in the steering control performed by the control device 50 or the control device 100. The host control device 500, for example, calculates an additional angle command value for making the vehicle travel in the target lane as the command value θ*. The additional angle command value is a target value of the pinion angle θ p or the steering angle θ s (to be added to the current pinion angle θ p or the steering angle θ s ) required for the vehicle to travel along the lane for the travel state of the vehicle at any given time. As indicated by the long and two short dashed lines alternately in Figure 3 , the command value θ* is added to the target pinion angle θ p * or the target steering angle θ s * calculated by the target angle calculation unit 73.

[0068] In the first embodiment and the second embodiment, the angle feedback control unit 74 or the angle feedback control unit 105 that does not include the feedforward control unit 82 can be employed.

[0069] Other technical ideas

[0070] Next, the technical idea that can be obtained according to the first embodiment and the second embodiment will be described below. The electric motor is an assist electric motor, a wheel steering electric motor, or a reaction electric motor. The assist electric motor is a source for generating an assist force. The wheel steering electric motor is a source for generating a wheel steering force. The reaction electric motor is a source for generating a steering reaction force.

Claims

1. A control device (50; 100) for an electric machine (21) for rotating a steered wheel (12) of a vehicle, characterized in that: including an electronic control unit, wherein the electronic control unit includes a first controller (81), a second controller (83), a third controller (84), and a fourth controller (85); the first controller (81) is configured to calculate a feedback control torque to be generated by the motor (21) through execution of feedback control that causes an angle that can be converted into a wheel steering angle of the steered wheels (12) to follow a target angle; the second controller (83) is configured to calculate a disturbance torque based on a predetermined angle and the feedback control torque calculated by the first controller, the predetermined angle being an angle that can be converted into the wheel steering angle and detected by a sensor, the disturbance torque being a torque that affects the angle that can be converted into the wheel steering angle, other than a torque to be generated by the motor (21); the third controller (84) is configured to correct the feedback control torque calculated by the first controller (81) by using the disturbance torque calculated by the second controller (83); and the fourth controller (85) is configured to compensate for a transfer time lag between the predetermined angle to the second controller (83) and the feedback control torque calculated by the first controller (81), delay the feedback control torque calculated by the first controller (81) by a delay of the predetermined angle with respect to the feedback control torque calculated by the first controller (81), the electronic control unit executes control of the motor (21) based on the feedback control torque.

2. The control device (50; 100) according to claim 1, characterized in that the electronic control unit further includes a fifth controller (82) configured to calculate a feedforward control torque based on a second-order time derivative of the target angle; and the third controller (84) is configured to subtract the disturbance torque from a value obtained by adding the feedforward control torque to the feedback control torque calculated by the first controller (81).

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