Motor control device

Abstract

The present application relates to a motor control device. A manual steering operation command value arithmetic unit is configured to use road surface information including information about a road surface reaction force torque for arithmetic of a manual steering operation command value when a first condition is satisfied, and not to use the road surface information for arithmetic of the manual steering operation command value when the first condition is not satisfied, wherein the first condition is that at least one of input torques in which a dead zone processing unit is provided is outside a dead zone range, and wherein the manual steering operation command value arithmetic unit uses the road surface information for arithmetic of the manual steering operation command value for a certain period from a time when a state in which the first condition is satisfied changes to a state in which the first condition is not satisfied, in a case in which a warning vibration torque is applied.

Description

Technical Field

[0001] This invention relates to a control device for an electric motor used for steering angle control. Background Technology

[0002] Patent Document 1 disclosed below discloses a motor control device that performs angle feedback control on an electric motor based on a comprehensive angle command value obtained by adding an automatic steering control command value and a manual steering control command value.

[0003] Patent Document 2 discloses a vehicle steering device comprising: a vibration torque calculation unit that calculates a warning vibration torque when it is determined that the vehicle has left its lane; and a current control unit that controls an electric motor to apply vibration to the steering wheel by using the vibration torque calculated by the vibration torque calculation unit. The vibration torque calculation unit sets a value for the vibration torque such that a larger steering torque detected by a torque sensor results in a larger vibration torque value, and a smaller steering torque results in a smaller vibration torque value. Specifically, the vibration torque calculation unit pre-stores a mapping that stores the relationship between the peak values ​​of the steering torque and the vibration torque, and sets the vibration torque based on the steering torque detected by the torque sensor and this mapping.

[0004] Patent Document 1: Japanese Patent Application Publication No. 2019-194059

[0005] Patent Document 2: Japanese Patent Application Publication No. 2017-65587 Summary of the Invention

[0006] The purpose of this invention is to provide a motor control device that can control an electric motor based on a comprehensive angle command value obtained by adding an automatic steering control command value and a manual steering control command value. This motor control device is suitable for applying warning vibrations to the steering wheel according to the driving state of the vehicle.

[0007] One embodiment of the present invention provides a motor control device for driving and controlling an electric motor for steering angle control. The device includes: an auxiliary torque command value setting unit that calculates an auxiliary torque command value using a steering torque; a manual steering command value calculation unit that calculates a manual steering command value using the steering torque and the auxiliary torque command value; a comprehensive angle command value calculation unit that calculates a comprehensive angle command value by adding the automatic steering command value and the manual steering command value; a control unit that performs angle control on the electric motor based on the comprehensive angle command value; and a dead-zone processing unit that, when the steering torque input to the manual steering command value calculation unit, the auxiliary torque command value input to the manual steering command value calculation unit, and the steering torque input to the auxiliary torque command value setting unit are set as input torques... The dead zone processing unit is provided for at least one of the aforementioned input torques; and a warning vibration application unit is provided for applying a warning vibration torque as a component of the motor torque command value of the electric motor. The manual steering operation command value calculation unit is configured to use road information containing information related to the road reaction torque to calculate the manual steering operation command value when a first condition is met, and not use the road information to calculate the manual steering operation command value when the first condition is not met. The first condition is that at least one of the input torques for which the dead zone processing unit is provided is outside the dead zone range. When the warning vibration torque is applied, the manual steering operation command value calculation unit uses the road information to calculate the manual steering operation command value for a certain period of time from the moment when the state of meeting the first condition changes to the moment when the state of not meeting the first condition is met.

[0008] In this structure, a motor control device suitable for applying warning vibrations to the steering wheel according to the driving status of the vehicle can be obtained.

[0009] The above-mentioned or other objects, features, and effects of the present invention will become clear from the following description of the embodiments with reference to the accompanying drawings. Attached Figure Description

[0010] Figure 1 This is a schematic diagram showing the general structure of an electric power steering system that utilizes a motor control device according to an embodiment of the present invention.

[0011] Figure 2 This is a block diagram used to illustrate the electrical structure of an ECU for motor control.

[0012] Figure 3 This indicates the steering torque T. tb Auxiliary torque command value T as The diagram shows the configuration example.

[0013] Figure 4 This is a block diagram showing the structure of the angle control unit.

[0014] Figure 5 This is a schematic diagram illustrating a structural example of the physical model of an electric power steering system.

[0015] Figure 6 This is a block diagram showing the structure of the disturbance torque estimation unit.

[0016] Figure 7 This is a schematic diagram showing the structure of the torque control unit.

[0017] Figure 8 This is a block diagram showing the structure of the manual steering control command value calculation unit.

[0018] Figure 9 It is a graph representing the input / output characteristics of the first dead zone processing unit.

[0019] Figure 10 This is a graph representing the input / output characteristics of the second dead zone processing unit.

[0020] Figure 11A This is a flowchart illustrating a part of the decision processing performed by the decision unit in driver assistance mode.

[0021] Figure 11B This is a flowchart illustrating a part of the decision processing performed by the decision unit in driver assistance mode.

[0022] Figure 12 This is a time graph representing an example of a vibration waveform in warning mode. Detailed Implementation

[0023] [Description of embodiments of the present invention]

[0024] One embodiment of the present invention provides a motor control device for driving and controlling an electric motor for steering angle control, comprising: an auxiliary torque command value setting unit that calculates an auxiliary torque command value using a steering torque; a manual steering command value calculation unit that calculates a manual steering command value using the steering torque and the auxiliary torque command value; a comprehensive angle command value calculation unit that calculates a comprehensive angle command value by adding an automatic steering command value and the manual steering command value; a control unit that performs angle control on the electric motor based on the comprehensive angle command value; and a dead zone processing unit that, when the steering torque input to the manual steering command value calculation unit, the auxiliary torque command value input to the manual steering command value calculation unit, and the steering torque input to the auxiliary torque command value setting unit are set as input torques, performs dead zone processing on the electric motor. At least one of the aforementioned input torques is provided with the aforementioned dead zone processing unit; and a warning vibration application unit is used to apply a warning vibration torque as a component of the motor torque command value of the aforementioned electric motor. The aforementioned manual steering operation command value calculation unit is configured to use road information containing information related to the road reaction torque to calculate the aforementioned manual steering operation command value when a first condition is met, and not use the aforementioned road information to calculate the aforementioned manual steering operation command value when the first condition is not met. The aforementioned first condition is that at least one of the aforementioned input torques provided with the aforementioned dead zone processing unit is outside the dead zone range. When the aforementioned warning vibration torque is applied, the aforementioned manual steering operation command value calculation unit uses the aforementioned road information to calculate the aforementioned manual steering operation command value for a certain period of time from the moment when the state of meeting the aforementioned first condition changes to the moment when the state of not meeting the aforementioned first condition changes.

[0025] In this structure, a motor control device suitable for applying warning vibrations to the steering wheel according to the driving status of the vehicle can be obtained.

[0026] In one embodiment of the present invention, the dead zone processing unit includes a first dead zone processing unit for the steering torque input to the manual steering command value calculation unit, and a second dead zone processing unit for the auxiliary torque command value input to the manual steering command value calculation unit.

[0027] In one embodiment of the present invention, the road surface information is calculated based on the comprehensive torque command value corresponding to the comprehensive angle command value and the steering angle, and is the high-frequency component of the estimated value of the disturbance torque applied to the steering shaft.

[0028] In one embodiment of the present invention, the warning vibration application unit is configured to output a vibration torque command value corresponding to the target warning vibration waveform, and the vibration torque command value is added to a comprehensive torque command value corresponding to the comprehensive angle command value.

[0029] In one embodiment of the present invention, the warning vibration application unit is configured to output a vibration angle command value corresponding to the target warning vibration waveform, and the vibration angle command value is added to the comprehensive angle command value.

[0030] [Detailed Description of Embodiments of the Invention]

[0031] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0032] Figure 1 This is a schematic diagram showing the general structure of an electric power steering system that utilizes a motor control device according to an embodiment of the present invention.

[0033] The electric power steering system 1 includes a steering wheel 2 as a steering control component for steering the vehicle, a steering mechanism 4 that is linked to the rotation of the steering wheel 2 and turns the steering wheels 3, and a steering control assist mechanism 5 for assisting the driver in steering control. The steering wheel 2 and the steering mechanism 4 are mechanically connected via a steering shaft 6 and an intermediate shaft 7.

[0034] The steering shaft 6 includes an input shaft 8 connected to the steering wheel 2 and an output shaft 9 connected to the intermediate shaft 7. The input shaft 8 and the output shaft 9 are connected by a torsion bar 10 so that they can rotate relative to each other.

[0035] A torque sensor 12 is disposed near the torsion bar 10. The torque sensor 12 detects the steering torque (torsion bar torque) T applied to the steering wheel 2 based on the relative rotational displacement of the input shaft 8 and the output shaft 9. tb In this embodiment, the steering torque T detected by torque sensor 12... tb For example, the torque used for steering to the left is detected as a positive value, and the torque used for steering to the right is detected as a negative value. The larger the absolute value, the greater the steering torque T. tb The larger the size.

[0036] The steering mechanism 4 is composed of a rack and pinion mechanism including a pinion shaft 13 and a rack shaft 14 serving as the steering shaft. Steering wheels 3 are connected to each end of the rack shaft 14 via tie rods 15 and steering knuckle arms (not shown). The pinion shaft 13 is connected to the intermediate shaft 7. The pinion shaft 13 rotates in conjunction with the steering operation of the steering wheel 2. A pinion 16 is connected to the front end of the pinion shaft 13.

[0037] The rack shaft 14 extends in a straight line along the left-right direction of the vehicle. A rack 17 is formed at the middle of the axial direction of the rack shaft 14, which meshes with the pinion 16. Through the pinion 16 and the rack 17, the rotation of the pinion shaft 13 is converted into the axial movement of the rack shaft 14. By moving the rack shaft 14 axially, the steering wheel 3 can be turned.

[0038] If the steering wheel 2 is turned, the rotation is transmitted to the pinion shaft 13 via the steering shaft 6 and the intermediate shaft 7. Then, the rotation of the pinion shaft 13 is converted into axial movement of the rack shaft 14 via the pinion 16 and the rack 17. As a result, the steering wheel 3 turns.

[0039] The steering assist mechanism 5 includes an electric motor 18 for generating steering assist force (assist torque) and a reducer 19 for amplifying the output torque of the electric motor 18 and transmitting it to the steering mechanism 4. The reducer 19 is composed of a worm mechanism including a worm 20 and a worm wheel 21 meshing with the worm 20. The reducer 19 is housed within a gear housing 22, which serves as the housing of the transmission mechanism.

[0040] The following cases involve N representing the reduction ratio (transmission ratio) of reducer 19. The reduction ratio N is defined as the rotation angle of the worm 20, i.e., the worm angle θ. wg The rotation angle relative to worm gear 21, i.e., the worm gear angle θ ww The ratio (θ) wg / θ ww ).

[0041] The worm gear 20 is driven to rotate by the electric motor 18. In addition, the worm wheel 21 is rotatably connected to the output shaft 9.

[0042] If the worm gear 20 is driven by the rotation of the electric motor 18, the worm wheel 21 is driven to rotate, applying motor torque to the steering shaft 6, and the steering shaft 6 (output shaft 9) rotates. The rotation of the steering shaft 6 is then transmitted to the pinion shaft 13 via the intermediate shaft 7. The rotation of the pinion shaft 13 is converted into axial movement of the rack shaft 14. Thus, the steering wheel 3 turns. That is, by rotating the worm gear 20 by the electric motor 18, steering assistance based on the electric motor 18 and steering of the steering wheel 3 are possible. A rotation angle sensor 23 is provided in the electric motor 18 for detecting the rotation angle of the rotor of the electric motor 18.

[0043] As a torque applied to the output shaft 9 (an example of the object driven by the electric motor 18), there exists the motor torque generated by the electric motor 18, and a disturbance torque T other than the motor torque. lc The disturbance torque T other than the motor torque. lc Includes steering torque T tb Road load torque (road reaction torque) Trl Friction torque T f wait.

[0044] Steering torque T tb The torque is applied to the output shaft 9 from the steering wheel 2 side by the force applied by the driver to the steering wheel 2, the force generated by steering inertia, etc.

[0045] Road load torque T rl The torque is applied to the output shaft 9 from the steering wheel 3 side via the rack shaft 14 through the self-aligning torque generated by the tire, the force generated by the suspension and tire alignment, the friction force of the rack and pinion mechanism, etc.

[0046] The vehicle is equipped with a CCD (Charge Coupled Device) camera 25 for photographing the road ahead of the vehicle in the direction of travel, a GPS (Global Positioning System) 26 for detecting the vehicle's position, a radar 27 for detecting road shape and obstacles, and a map information storage device 28 for storing map information, etc.

[0047] The CCD camera 25, GPS 26, radar 27, and map information storage 28 are connected to the upper-level ECU (Electronic Control Unit) 201 for driver assistance control. Based on the information obtained from the CCD camera 25, GPS 26, and radar 27, as well as map information, the upper-level ECU 201 performs surrounding environment recognition, vehicle position estimation, path planning, and determines the control target values ​​for steering and drive actuators.

[0048] In this embodiment, there are two driving modes: a normal mode and a driving assistance mode. In this embodiment, when the host ECU 201 is in driving assistance mode, it generates an automatic steering control command value θ for driving assistance mode based on information obtained from the CCD camera 25, GPS 26, radar 27, and map information. ad,cmd .

[0049] In this embodiment, the driving assistance is Lane Centering Assist (LCA), which enables the vehicle to automatically follow the center of the lane (lane center). Automatic steering command value θ ad,cmd This is the target value for the steering angle (in this embodiment, the rotation angle of the pinion shaft 13) used to keep the vehicle moving along the center of the lane. Because such an automatic steering command value θ is set... ad,cmdThe processing is well-known, so detailed explanations are omitted here. Furthermore, automatic steering control (driving assistance control) can also be, for example, lane keeping assist (LKA) control used to keep the vehicle within its lane.

[0050] Furthermore, the host ECU 201 determines the likelihood of the vehicle leaving the lane based on images captured by the CCD camera 25. In this embodiment, when the host ECU 201 determines that the likelihood of the vehicle leaving the lane is high, it generates and outputs a vibration torque command value T corresponding to the waveform of the warning vibration that should be applied to the steering wheel 2 (hereinafter referred to as the "target warning vibration waveform"). wa,cmd .

[0051] The vibration torque command value T will be output from the host ECU201 below. wa,cmd This mode is called "warning mode". The host ECU201 outputs a warning mode signal S indicating whether it is in warning mode. wa,mode .

[0052] In addition, the host ECU201 generates a driving mode signal S indicating whether the driving mode is normal mode or driving assistance mode. dr,mode Driving mode signal S dr,mode Automatic steering control command value θ ad,cmd Warning mode signal S wa,mode and vibration torque command value T wa,cmd It is provided to the motor control ECU202 via the vehicle network.

[0053] Steering torque T detected by torque sensor 12 tb The output signal of the rotation angle sensor 23 is input to the motor control ECU 202. The motor control ECU 202 controls the electric motor 18 based on these input signals and information provided by the host ECU 201.

[0054] Figure 2 This is a block diagram used to explain the electrical structure of the ECU202 for motor control.

[0055] The following mainly explains the situation where the driving mode is driving assistance mode.

[0056] The motor control ECU 202 includes a microcomputer 50, a drive circuit (inverter circuit) 41 controlled by the microcomputer 50 and supplying power to the electric motor 18, and a current detection circuit 42 for detecting the current flowing through the electric motor 18 (hereinafter referred to as "motor current I").

[0057] The microcomputer 50 includes a CPU and memory (ROM, RAM, non-volatile memory, etc.), and functions as multiple functional processing units by executing a prescribed program. These multiple functional processing units include an auxiliary torque command value setting unit 51, a manual steering operation command value calculation unit 52, a comprehensive angle command value calculation unit 53, an angle control unit 54, a torque control unit (current control unit) 55, a switching switch 56, and an adder unit 57.

[0058] The auxiliary torque command value setting unit 51 sets the auxiliary torque command value T as the target value of the auxiliary torque required for manual operation. assist The auxiliary torque command setting unit 51 is based on the steering torque T detected by the torque sensor 12. tb To set the auxiliary torque command value T assist Regarding the steering torque T tb Auxiliary torque command value T assist The setting example is in Figure 3 As shown in the image.

[0059] For the auxiliary torque command value T assist Specifically, the auxiliary torque command value T is set to a positive value when the electric motor 18 should generate a steering assist force for left-hand steering and a negative value when the electric motor 18 should generate a steering assist force for right-hand steering. assist For steering torque T tb The positive value is taken as positive, for steering torque T. tb Negative values ​​are taken as negative. Furthermore, the auxiliary torque command value T... assist Set as steering torque T tb The larger the absolute value, the larger its absolute value. Auxiliary torque command value T assist It is input to the first input terminal of the switch 56.

[0060] Furthermore, the auxiliary torque command value setting unit 51 can also take into account the vehicle speed detected by a vehicle speed sensor (not shown) when setting the auxiliary torque command value T. assist In this case, the auxiliary torque command value T assist Set as steering torque T tb The larger the absolute value, the larger the absolute value; the higher the vehicle speed, the smaller the absolute value.

[0061] The auxiliary torque command value setting unit 51 can also set the steering torque T by... tb The auxiliary torque command value T is calculated by multiplying it by a pre-set constant. assist .

[0062] In order to set the steering angle (more precisely, the rotation angle of the pinion shaft 13) corresponding to the steering wheel operation to the manual steering command value θ when the driver operates the steering wheel 2. md,cmd A manual steering command value calculation unit 52 is provided. The manual steering command value calculation unit 52 uses the steering torque T detected by the torque sensor 12. tb and the auxiliary torque command value T set by the auxiliary torque command value setting unit 51. assist To generate manual steering control command value θ md,cmd Details regarding the manual steering command value calculation unit 52 will be described later.

[0063] The integrated angle command value calculation unit 53 calculates the automatic steering control command value θ set by the upper ECU 201. ad,cmd With manual steering control command value θ md,cmd Add them together to calculate the combined angle command value θ. sint,cmd .

[0064] Angle control unit 54 based on comprehensive angle command value θ sint,cmd Calculation and synthesis of the angle instruction value θ sint,cmd The corresponding comprehensive motor torque command value T mint,cmd Comprehensive motor torque command value T mint,cmd The input is sent to the second input terminal of the switch 56. The combined motor torque command value T mint This is an example of the "comprehensive torque command value" in this invention. Details regarding the angle control unit 54 will be described later.

[0065] Switch 56 changes according to driving mode signal S dr,mode Output auxiliary torque command value T assist and the comprehensive motor torque command value T mint,cmd One of them is used as the first motor torque command value T m1,cmd Specifically, when the driving mode is in driving assistance mode, switch 56 outputs the combined motor torque command value T. mint,cmd The first motor torque command value T m1,cmd The first motor torque command value T m1,cmd It was provided to the Addition Department 57.

[0066] On the other hand, when the driving mode is normal, the switch 56 outputs the auxiliary torque command value T. assist The first motor torque command value T m1,cmd The first motor torque command value T m1,cmd It was provided to the Addition Department 57.

[0067] The vibration torque command value T was not output from the upper ECU201.wa,cmd In this case, the addition unit 57 will input the first motor torque command value T. m1,cmd The calculation yields the final motor torque command value T. m,cmd The upper-level ECU201 outputs a vibration torque command value T. wa,cmd In this case, the addition unit 57 calculates the first motor torque command value T. m1,cmd With vibration torque command value T wa,cmd The sum of these values ​​is used as the final motor torque command value T. m,cmd .

[0068] The torque control unit 55 drives the drive circuit 41, causing the motor torque of the electric motor 18 to approach the motor torque command value T. m,cmd .

[0069] Figure 4 This is a block diagram showing the structure of the angle control unit 54.

[0070] Angle control unit 54 based on comprehensive angle command value θ sint,cmd Calculate the overall motor torque command value T mint,cmd The angle control unit 54 includes a low-pass filter (LPF) 61, a feedback control unit 62, a feedforward control unit 63, an interference torque estimation unit 64, a torque addition unit 65, an interference torque compensation unit 66, a first reduction ratio division unit 67, a reduction ratio multiplication unit 68, a rotation angle calculation unit 69, and a second reduction ratio division unit 70.

[0071] The reduction ratio multiplier 68 is controlled by a switching switch 56 (see reference). Figure 2 The first motor torque command value T calculated m1,cmd Multiply by the reduction ratio N of reducer 19 to obtain the first motor torque command value T. m1,cmd Converted to the pinion shaft torque command value (N·T) acting on pinion shaft 13 (worm gear 21) m1,cmd .

[0072] The rotation angle calculation unit 69 calculates the rotor rotation angle θ of the electric motor 18 based on the output signal of the rotation angle sensor 23. m The second reduction ratio division unit 70 calculates the rotor rotation angle θ by the rotation angle calculation unit 69. m Divide by the reduction ratio N, thus increasing the rotor rotation angle θ. m Converted to the rotation angle (actual steering angle) of pinion shaft 13 θ p .

[0073] Low-pass filter 61 combines the angle command value θ sint,cmd Low-pass filtering is performed. The resulting composite angle command value θ is obtained after low-pass filtering. sin,cmd It is provided to the feedback control unit 62 and the feedforward control unit 63.

[0074] To make the steering angle estimate calculated by the disturbance torque estimation unit 64 ^θ p The combined angle command value θ after close low-pass filtering sin,cmd A feedback control unit 62 is provided. The feedback control unit 62 includes an angle deviation calculation unit 62A and a PD control unit 62B. The angle deviation calculation unit 62A calculates the comprehensive angle command value θ. sin,cmd With the estimated steering angle ^θ p The deviation Δθ (=θ) sin,cmd -^θ p Furthermore, the angle deviation calculation unit 62A can also calculate the comprehensive angle command value θ. sin The steering angle θ calculated by the second reduction ratio divider 70 p deviation (θ) sin,cmd -θ p ) is used as the angular deviation Δθ.

[0075] The PD control unit 62B calculates the feedback control torque T by performing PD calculation (proportional-derivative calculation) on the angle deviation Δθ calculated by the angle deviation calculation unit 62A. fb Feedback control torque T fb It is supplied to the torque adding unit 65.

[0076] A feedforward control unit 63 is provided to compensate for the responsiveness delay caused by inertia in the electric power steering system 1, thereby improving the control responsiveness. The feedforward control unit 63 includes an angular acceleration calculation unit 63A and an inertia multiplication unit 63B. The angular acceleration calculation unit 63A calculates the comprehensive angle command value θ... sin,cmd Perform a second-order differential to calculate the target angular acceleration d. 2 θ sin,cmd / dt 2 .

[0077] The inertial multiplication unit 63B multiplies the target angular acceleration d calculated by the angular acceleration calculation unit 63A. 2 θ sin,cmd / dt 2 Multiply by the inertia J of the electric power steering system 1 to calculate the feedforward control torque T. ff (=J·d 2 θ sin,cmd / dt 2 For example, according to the physical model 121 of the electric power steering system 1 described later (refer to...). Figure 5 Calculate the inertia J. Calculate the feedforward control torque T. ff The inertia compensation value is provided to the torque addition unit 65.

[0078] The torque adder 65 controls the torque T by feeding back the torque.fb With feedforward control torque T ff Add them together to calculate the basic torque command value (T). fb +T ff ).

[0079] An interference torque estimation unit 64 is provided to estimate the nonlinear torque (interference torque: torque other than motor torque) generated as an disturbance in the mechanical device (the controlled object of the electric motor 18). The interference torque estimation unit 64 is based on the pinion shaft torque command value N·T. m1,cmd and steering angle θ p To estimate the disturbance torque (disturbing load) T lc Steering angle θ p And the differential value of the steering angle (angular velocity) dθ p / dt. Disturbance torque T lc Steering angle θ p And the differential value of the steering angle (angular velocity) dθ p The estimated values ​​of / dt are respectively expressed in terms of ^T lc ,^θ p and d^θ p / dt represents the value. Details regarding the disturbance torque estimation unit 64 will be discussed later.

[0080] The disturbance torque estimate ^T calculated by the disturbance torque estimation unit 64 lc As a disturbance torque compensation value, it is provided to the disturbance torque compensation unit 66 and to the manual steering control command value calculation unit 52 (see reference). Figure 2 The estimated steering angle ^θ calculated by the disturbance torque estimation unit 64. p It is provided to the angle deviation calculation unit 62A.

[0081] The disturbance torque compensation unit 66 obtains the basic torque command value (T) from the basic torque command value (T). fb +T ff Subtract the estimated disturbance torque value ^T lc To calculate the comprehensive steering torque command value T pint,cmd (=T fb +T ff -^T lc Therefore, the comprehensive steering torque command value T after compensating for the disturbance torque is obtained. pint,cmd (Torque command value for pinion shaft 13).

[0082] Comprehensive steering torque command value T pint,cmd It is provided to the first reduction ratio divider 67. The first reduction ratio divider 67 measures the overall steering torque command value T. pint,cmd Divide by the reduction ratio N to calculate the overall motor torque command value T.mint,cmd The comprehensive motor torque command value T mint,cmd Provided to switch 56 (see reference) Figure 2 ).

[0083] The disturbance torque estimation unit 64 will be described in detail. The disturbance torque estimation unit 64 is, for example, composed of a disturbance observer, which uses... Figure 5 The physical model 121 of the electric power steering system 1 shown is used to estimate the disturbance torque T. lc Steering angle θ p and angular velocity dθ p / dt.

[0084] The physical model 121 includes a mechanical device (an example of a motor-driven object) 122 comprising an output shaft 9 and a worm gear 21 fixed to the output shaft 9. A steering torque T is applied to the mechanical device 122 from the steering wheel 2 via a torsion bar 10. tb And apply the road reaction torque T to the mechanical equipment 122 from the side of the steering wheel 3. rl .

[0085] Furthermore, the pinion shaft torque command value N·T is applied to the mechanical device 122 via the worm gear 20. m1,cmd Furthermore, a frictional torque T is applied to the mechanical device 122 due to the friction between the worm gear 21 and the worm 20. f .

[0086] When the inertia of the mechanical device 122 is set as J, the equation of motion for the inertia of the physical model 121 is expressed by the following equation (3).

[0087] [Number 1]

[0088]

[0089] Tlc=Ttb+Trl+Tf

[0090] d 2 θp / dt 2 ω is the angular acceleration of mechanical device 122. N is the reduction ratio of reducer 19. Tlc represents the disturbance torque applied to mechanical device 122 other than the motor torque. In this embodiment, the disturbance torque Tl c It is expressed as steering torque Tt b Road surface reaction torque Tr l and frictional torque T f The sum, but actually the disturbance torque Tl c Includes torque other than those.

[0091] against Figure 5The state equation of the physical model 121 is represented by the following equation (4).

[0092] [Number 2]

[0093]

[0094] In equation (4) above, x is the state variable vector, u1 is the known input vector, u2 is the unknown input vector, and y is the output vector (measured value). In addition, in equation (4) above, A is the system matrix, B1 is the first input matrix, B2 is the second input matrix, C is the output matrix, and D is the direct matrix.

[0095] The above state equations are extended to include an unknown input vector u2 as one of the states. The state equations of the extended system (extended state equations) are represented by the following equation (5).

[0096] [Number 3]

[0097]

[0098] In equation (5) above, x e It is the state variable vector of the extended system, represented by the following equation (6).

[0099] [Number 4]

[0100]

[0101] In the above equation (5), A e It is the system matrix of the extended system, B e C is the known input matrix of the extended system. e It is the output matrix of the extended system.

[0102] Based on the extended state equation of equation (5) above, an interference observer (extended state observer) represented by the equation (7) below is constructed.

[0103] [Number 5]

[0104]

[0105] In equation (7), ^x e x represents e The estimated value of y. Additionally, L is the observer gain. Furthermore, ^y represents the estimated value of y. ^x e It is represented by the following formula (8).

[0106] [Number 6]

[0107]

[0108] In equation (8), ^θ pIt is θ p The estimated value, ^T lc It is T lc The estimated value.

[0109] The disturbance torque estimation unit 64 calculates the state variable vector ^x based on the equation (7) above. e .

[0110] Figure 6 This is a block diagram showing the structure of the disturbance torque estimation unit 64.

[0111] The disturbance torque estimation unit 64 includes an input vector input unit 81, an output matrix multiplication unit 82, a first addition unit 83, a gain multiplication unit 84, an input matrix multiplication unit 85, a system matrix multiplication unit 86, a second addition unit 87, an integrator unit 88, and a state variable vector output unit 89.

[0112] From the reduction ratio multiplication part 68 (refer to) Figure 4 The pinion shaft torque command value N·T calculated m1,cmd It is provided to the input vector input section 81. The input vector input section 81 outputs the input vector u1.

[0113] The output of the integrator 88 becomes the state variable vector ^x e (Refer to equation (8) above). At the start of the operation, initial values ​​are provided as the state variable vector ^x. e State variable vector ^x e The initial value is, for example, 0.

[0114] The system matrix multiplication unit 86 multiplies the state variable vector ^x e Multiply by system matrix A e The output matrix multiplication unit 82 will multiply the state variable vector ^x e Multiply by the output matrix C e .

[0115] The first addition section 83 is derived from the second reduction ratio division section 70 (see reference). Figure 4 The calculated steering angle θ p That is, the output vector (measured value) y minus the output of the multiplication part 82 of the output matrix (C) e ·^x e That is, the first addition unit 83 operates on the output vector y and the output vector estimate ^y(=C e ·^x e The difference (y-^y) is calculated by multiplying the output (y-^y) of the first adder 83 by the observer gain L (refer to equation (7) above).

[0116] The input matrix multiplication unit 85 multiplies the input vector u1 output from the input vector input unit 81 by the input matrix B.e The second addition unit 87 inputs the output (Be·u1) of the input matrix multiplication unit 85 and the output (A) of the system matrix multiplication unit 86. e ·^x e The differential value d^x of the state variable vector is calculated by adding the output of the gain multiplication unit 84 (L(y-^y)) and the output of the gain multiplication unit 84. e / dt. The integral part 88 outputs (d^x) to the second addition part 87. e Integrate / dt to compute the state variable vector ^x e The state variable vector output unit 89 is based on the state variable vector ^x. e Operational disturbance torque estimate ^T lc The estimated steering angle ^θ and the estimated angular velocity d^θ / dt.

[0117] The general disturbance observer differs from the extended state observer described above, and consists of the inverse model of the mechanical device and a low-pass filter. The equation of motion of the mechanical device is expressed by equation (3) as described above. Therefore, the inverse model of the mechanical device is equation (9).

[0118] [Number 7]

[0119]

[0120] The input to a typical interference observer is J·d 2 θ p / dt 2 and N·T m1,cmd Using the steering angle θ p The second derivative value is therefore significantly affected by the noise of the rotation angle sensor 23. In contrast, in the extended state observer of the above embodiment, since the disturbance torque is estimated using an integral form, the noise caused by the derivative can be reduced.

[0121] Furthermore, as the interference torque estimation unit 64, a general interference observer composed of an inverse model of a mechanical device and a low-pass filter can also be used.

[0122] Figure 7 This is a schematic diagram showing the structure of the torque control unit 55.

[0123] Torque control unit 55 (reference) Figure 2 It includes a motor current command value calculation unit 91, a current deviation calculation unit 92, a PI control unit 93, and a PWM (Pulse Width Modulation) control unit 94.

[0124] The motor current command value calculation unit 91 calculates the current by adding the value from the addition unit 57 (see reference). Figure 2The calculated motor torque command value T m,cmd Divide by the torque constant K of electric motor 18 t To calculate the motor current command value I m,cmd .

[0125] The current deviation calculation unit 92 calculates the motor current command value I obtained from the motor current command value calculation unit 91. m,cmd The motor current I detected by the current detection circuit 42 m The deviation ΔI (=I m,cmd -I m ).

[0126] The PI control unit 93 generates a motor current I flowing through the electric motor 18 by performing a PI calculation (proportional-integral calculation) on the current deviation ΔI calculated by the current deviation calculation unit 92. m Guided to motor current command value I m,cmd The drive command value is obtained. The PWM control unit 94 generates a PWM control signal with a duty cycle corresponding to the drive command value and supplies the PWM control signal to the drive circuit 41. As a result, power corresponding to the drive command value is supplied to the electric motor 18.

[0127] The manual steering control command value calculation unit 52 will be described in detail below.

[0128] Figure 8 This is a block diagram showing the structure of the manual steering control command value calculation unit 52.

[0129] The manual steering control command value calculation unit 52 includes a high-pass filter 101, a determination unit 102, a first dead zone processing unit 103, a second dead zone processing unit 104, and a command value calculation unit 105.

[0130] The high-pass filter 101 extracts the estimated interference torque value ^T from the interference torque estimation unit 64. lc High-frequency component HPF(^T) lc In this embodiment, the estimated disturbance torque value is ^T. lc High-frequency component HPF(^T) lc This is an example of "road information containing at least information about road reaction torque" in this invention.

[0131] Steering torque T tb It is input into the first dead zone processing unit 103. For example... Figure 9 As shown, when the first dead zone width is set to W1, the steering torque T tbWhen the range is greater than or less than -W1 / 2 (the first dead zone region), the first dead zone processing unit 103 outputs zero as the steering torque T after the first dead zone processing. tb,de .

[0132] Steering torque T tb In the region smaller than -W1 / 2, the first dead zone processing unit 103 outputs [T] tb +(W1 / 2)] is the steering torque T after processing the first dead zone. tb,de In steering torque T tb For areas larger than W1 / 2, the first dead zone processing unit 103 outputs [T]. tb -(W1 / 2)] is the steering torque T after processing the first dead zone. tb,de .

[0133] Auxiliary torque T assist It is input into the second dead zone processing unit 104. For example... Figure 10 As shown, when the second dead zone width is set to W2, the auxiliary torque T assist When the range is greater than or less than -W2 / 2 (the second dead zone region), the second dead zone processing unit 104 outputs zero as the auxiliary torque T after the second dead zone processing. assist,de .

[0134] In the auxiliary torque T assist In the region smaller than -W2 / 2, the second dead zone processing unit 104 outputs [T] assist +(W2 / 2)] is the auxiliary torque T after the second dead zone treatment. assist,de In the auxiliary torque T assist For areas larger than W2 / 2, the second dead zone processing unit 104 outputs [T]. assist -(W2 / 2)] is the auxiliary torque T after the second dead zone is processed. assist,de .

[0135] The determination unit 102 is based on the warning mode signal S wa,mode Steering torque T tb and auxiliary torque command value T assist Determine whether the manual steering control command value θ is being used. md,cmd The calculation uses the disturbance torque estimate ^T lc High-frequency component HPF(^T) lc Then, the manual steering control command value θ is determined. md,cmd The calculation uses the disturbance torque estimate ^T lc High-frequency component HPF(^T) lc In the case of ), the decision unit 102 determines the variable T. x Set HPF(^T)lc ), when determined to be in manual steering control command value θ md,cmd The disturbance torque estimate ^T is not used in the calculation. lc High-frequency component HPF(^T) lc In the case of ), for variable T x Set to 0.

[0136] Figure 11A as well as Figure 11B This is a flowchart illustrating the decision processing performed by the decision unit 102 in driving assistance mode.

[0137] Figure 11A as well as Figure 11B The decision processing shown in steps S4 to S18 is repeated every specified operation cycle Δt.

[0138] Reference Figure 11A When the power is turned on (step S1), the determination unit 102 sets the count value k to 0 (step S2) and sets the latch flag T. x_switch_latch Set to 0 (step S3). Then, the determination unit 102 moves to step S4.

[0139] In step S4, the determination unit 102 determines whether the steering torque T is satisfied. tb absolute value |T tb | is the value outside the first dead zone or the auxiliary torque command value T. assist absolute value |T assist The condition for determining whether the area is outside the second dead zone is |T. Specifically, if |T| is satisfied... tb The first condition |>(W1 / 2) and |T assist If at least one of the second conditions (W2 / 2) is met, the determination unit 102 determines that the determination condition is satisfied. On the other hand, if neither the first nor the second condition is satisfied, i.e., the steering torque T is not satisfied... tb Within the first dead zone region and the auxiliary torque command value T assist If the area is within the second dead zone, the determination unit 102 determines that the determination conditions are not met.

[0140] If the determination condition is met in step S4 (step S4: "Yes"), the determination unit 102 will switch the flag T. x_switch Set to 1 (step S5). Additionally, the determination unit 102 latches the flag T. x_switch_latch The value is set to 1 (step S6). Then, after setting the count value k to 0 (step S7), the determination unit 102 moves to step S14.

[0141] If the determination condition is not met in step S4 (step S4: "No"), such as Figure 11B As shown, the determination unit 102 will switch the flag T. x_switch Set to 0 (step S8).

[0142] Next, the determination unit 102 determines the latch flag T. x_switch_latch Should it be set to 1 (step S9)?

[0143] At latch flag T x_switch_latch If the value is set to 0 (step S9: "No"), the determination unit 102 moves to step S14.

[0144] In step S9, it is determined that the latch flag T is... x_switch_latch If the value is set to 1 (step S9: "Yes"), the determination unit 102 increments the count value k by 1 (step S10). Then, the determination unit 102 determines whether the count value k is greater than a predetermined threshold k. _th Large (step S11). In other words, determine whether the time from when the count value k was set to 0 in the most recent step S7 to the current time is greater than (k... _th The specified time T of ×Δt) s Large. Regarding the specified time T s The setting example will be described later.

[0145] When the count value k is greater than the specified threshold k _th In the case of a large value (step S11: "Yes"), the determination unit 102 will latch the flag T. x_switch_latch After setting it to 0 (step S12), proceed to step S14.

[0146] In step S11, it is determined that the count value k is equal to the specified threshold k. _th In the following case (step S11: "No"), the determination unit 102 will latch the flag T x_switch_latch After setting it to 1 (step S13), proceed to step S14.

[0147] Return to Figure 11A In step S14, the determination unit 102 determines the warning mode signal S based on the warning mode signal S. wa,mode Determine whether it is in warning mode. If it is in warning mode (step S14: "Yes"), the determination unit 102 moves to step S16.

[0148] If it is determined in step S14 that it is not in the warning mode (step S14: "No"), the determination unit 102 latches the flag T. x_switch_latch Set the switching flag T x_switch The value is determined (step S15). Then, the determination unit 102 moves to step S16.

[0149] In step S16, the determination unit 102 determines the latch flag T. x_switch_latchIs it 1? In latch flag T x_switch_latch If the value is 1 (step S16: "Yes"), the determination unit 102 determines T. x Set HPF(^T) lc (Step S17). Then, the determination unit 102 returns to step S4.

[0150] In step S16, it is determined that the latch flag T is... x_switch_latch If the value is 0 (step S16: "No"), the determination unit 102 determines T. x Set to 0 (step S18). Then, the determination unit 102 returns to step S4.

[0151] For the specified time T s The following is an example of the settings. For instance, the vibration waveform in warning mode is shown below. Figure 12 Taking the waveform shown as an example, for a specified time T... s The following example will be used to illustrate the setup. Figure 12 In the warning mode shown, an interval T of 0.1 seconds is taken after six cycles of a target vibration waveform consisting of a 20Hz sine wave. A The waveforms formed by repeating the pattern three times constitute a group.

[0152] The specified time T s The preferred interval time T A The above is more preferably the interval time T. A The time T after adding the target vibration waveform of one period B That's all. Additionally, the specified time T... s The total time T of a preferred set of warning modes C the following.

[0153] exist Figure 12 In the warning mode, when the period T of the sine wave used as the target vibration waveform is... w When set to 0.05 seconds, the specified time T s Preferably 2×T w (=0.1 seconds) or more, more preferably 3×T w (=0.15 seconds) or more. Additionally, the specified time T... s Preferably 24×T w (=1.2 seconds) or less.

[0154] According to the judgment process in Figure 11, the steering torque T tb and auxiliary torque command value T assist If at least one of them is outside the dead zone (when the judgment condition is met), let it be T. x_switch =1,T x_switch_latch=1, k=0 (refer to steps S5, S6, S7). In this case, even if it is not in warning mode, it is set to T in step S15. x_switch_latch =1, therefore, regardless of whether it is in warning mode, let's set it to T. x =HPF(^T lc (Refer to steps S16 and S17).

[0155] On the other hand, in steering torque T tb and auxiliary torque command value T assist Let T represent the situation where both parties are within the dead zone (the situation where the judgment conditions are not met). x_switch =0 (refer to step S8). In this case, when it is determined to be T in step S9 x_switch_latch When = 0, it is set to T in step S15 even if it is not in warning mode. x_switch_latch =0, therefore, regardless of whether it is in warning mode, let's set it to T. x =0 (refer to steps S16 and S18).

[0156] That is, in the steering torque T tb and auxiliary torque command value T assist If at least one of them is outside the dead zone (when the judgment conditions are met), it is generally set to T. x =HPF(^T lc ). In steering torque T tb and auxiliary torque command value T assist In principle, the situation where both parties are within the dead zone (where the judgment conditions are not met) is denoted as T. x =0.

[0157] In step S9, it is determined to be T. x_switch_latch =1, and the elapsed time since the count value k was reset in the most recent step S7 is longer than the specified time T. s In the case of a large value, let it be T. x_switch_latch =0 (refer to step S12). In this case, even if it is not in warning mode, it is set to T in step S15. x_switch_latch =0, therefore, regardless of whether it is in warning mode, let's set it to T. x =0 (refer to steps S16 and S18).

[0158] In step S9, it is determined to be T. x_switch_latch =1, and the elapsed time since the count value k was reset in the most recent step S7 is a specified time T. s In cases where the condition is not met, it is still set to T. x_switch_latch=1 (refer to step S13). In this case, if it is not in warning mode, then it is set to T through the processing in step S15. x_switch_latch =0, therefore set to T x =0 (refer to steps S16 and S18). On the other hand, if it is in warning mode, step S15 is not performed, so it is set to T. x =HPF(^T lc (Refer to steps S16 and S17).

[0159] That is, in the next operation cycle after the operation cycle in step S7 where the count value k is set to 0, if the state of not meeting the determination condition continues, the elapsed time from when the count value k is set to 0 in step S7 is a predetermined time T. s If it is within the warning mode, set it to T. x =HPF(^T lc Subsequently, if the state that does not meet the judgment condition continues, let it be T. x =0.

[0160] This prevents the frequent repetition of T in warning mode. x =HPF(^T lc The state and T x =0.

[0161] The command value calculation unit 105 uses the benchmark EPS model to calculate the manual steering control command value θ. md,cmd The baseline EPS model is a single inertial model that includes the lower column.

[0162] Specifically, the command value calculation unit 105 calculates the manual steering command value θ by solving the differential equation of the following equation (10). md,cmd .

[0163] J md ·d 2 θ md,cmd / dt 2 =T tb,de +N·T assist,de -k1·θ md,cmd -c1(dθ) md,cmd / dt)

[0164] -T x …(10)

[0165] In equation (10), J md It is the inertia of the lower column, T tb,de This is the steering torque after the first dead zone is processed, N is the reduction ratio of reducer 19, and T is the steering torque after the first dead zone is processed. assist,deThis is the auxiliary torque after the second dead zone processing, k1 is the spring constant, c1 is the viscous damping coefficient, and T x These are variables set by the determination unit 102. In this embodiment, the spring constant k1 and the viscosity decay coefficient c1 are preset.

[0166] The following will be related to the steering torque T. tb Auxiliary torque command value T assist and warning mode signal S wa,mode Regardless, always use HPF(^T) lc ) as T in equation (10) x To calculate the manual steering control command value θ md,cmd The ECU used for motor control is referred to as the first comparative example.

[0167] In the first comparative example, in driver assistance mode, even when the driver does not intervene with steering, a result based on HPF(^T) is generated. lc The road surface reaction force results in poor tracking of the target driving path.

[0168] Therefore, considering the steering torque T tb and auxiliary torque command value T assist When at least one of them is outside the dead zone, for T of equation (10) x Set HPF(^T) lc ), in steering torque T tb and auxiliary torque command value T assist When both sides are within the dead zone, for equation (10) T x Set to 0. T will be used with this setting. x To calculate the manual steering control command value θ md,cmd The ECU used for motor control is referred to as the second comparative example.

[0169] That is, in the second comparative example, when the determination is affirmative ("yes") in step S4 of FIG11, for T x Set HPF(^T) lc In step S4 of Figure 11, if the decision is negative ("No"), then for T... x Set it to 0. In other words, if T x_switch =1, then for T x Set HPF(^T) lc If T x_switch =0, then for T x Set to 0.

[0170] In the second comparative example, in driver assistance mode, when the driver does not intervene with steering (T... tb And Tassist In the case where both sides are within the dead zone, no HPF-based (^T) generation will be performed. lc The road surface reaction force is reduced, thus improving the following performance on the target driving path compared to the first comparative example.

[0171] However, in warning mode, based on the vibration torque command value T wa,cmd Steering torque T tb and auxiliary torque command value T assist At least one of them is the state outside the dead zone region, and the steering torque T tb and auxiliary torque command value T assist Both sides frequently switch states within the dead zone. As a result, the manual steering command value θ... md,cmd With shorter periodic changes, the steering angle is moved too large.

[0172] In this embodiment, when not in warning mode, similar to the second comparative example, the steering torque T... tb and auxiliary torque command value T assist If at least one of them is outside the dead zone, then for T x Set HPF(^T) lc ), in steering torque T tb and auxiliary torque command value T assist When both sides are within the dead zone, for T x Set to 0. As a result, the following performance on the target driving path is better compared to the first comparative example.

[0173] Furthermore, in this embodiment, in the warning mode, when the steering torque T is reduced... tb and auxiliary torque command value T assist At least one of them changes its first state outside the dead zone region to the steering torque T. tb and auxiliary torque command value T assist When both sides are in the second state within the dead zone, for T x Continuously set HPF(^T) lc (), until a predetermined time T elapses from the moment the state changes from the first state to the second state. s This prevents the frequent repetition of T in warning mode. x =HPF(^T lc The state and T x =0. Therefore, it is possible to suppress manual steering command values ​​θ in warning mode. md,cmd With shorter cycle changes, it is able to suppress excessive movement of the steering angle in warning mode.

[0174] The embodiments and variations of the present invention have been described above, but the present invention can also be implemented in other ways.

[0175] In the above embodiments, in Figure 11A In step S17, the determination unit 102 determines T x Set HPF(^T) lc However, in Figure 11A In step S17, the determination unit 102 can also determine T. x Set the interference estimate ^T lc .

[0176] In addition, Figure 11A In step S17, the determination unit 102 can also determine T. x Set from the interference estimate ^T lc Subtract steering torque T tb The value after (^T) lc -T tb The high-frequency components of ) are also known as HPF(^T) lc -T tb ). It is possible to achieve this through (^T) lc -T tb High-pass filtering is performed to obtain HPF(^T) lc -T tb ).

[0177] In addition, Figure 11A In step S17, the determination unit 102 can also determine T. x Set from the interference estimate ^T lc Subtract steering torque T tb The value after (^T) lc -T tb ).

[0178] In addition, Figure 11A In step S17, the determination unit 102 can also determine T. x Set from the interference estimate ^T lc Subtract steering torque T tb and frictional torque T f The value after (^T) lc -T tb -T f The high-frequency components of ) are also known as HPF(^T) lc -T tb -T f ). It is possible to achieve this through (^T) lc -T tb -T f High-pass filtering is performed to obtain HPF(^T) lc -T tb -Tf Furthermore, for example, the frictional torque T can be estimated using a friction model that estimates the friction generated in the reducer 19. f .

[0179] In addition, Figure 11A In step S17, the determination unit 102 can also determine T. x Set from the interference estimate ^T lc Subtract steering torque T tb and frictional torque T f The value after (^T) lc -T tb -T f ).

[0180] Alternatively, instead of the aforementioned second dead zone processing unit 104, the steering torque T input to the auxiliary torque command value setting unit 51 can be adjusted. tb A third dead zone processing unit is provided. In this case, the dead zone width of the third dead zone processing unit can be the same as or different from the dead zone width W1 of the first dead zone processing unit 103. In this case, in Figure 11A In step S4, the determination unit 102 determines whether the steering torque T is satisfied. tb absolute value |T tb | is the torque T outside the first dead zone or the steering control torque tb absolute value |T tb |This condition is that the area outside the dead zone of the third dead zone processing department is outside the judgment area.

[0181] Alternatively, instead of the first dead zone processing unit 103 and the second dead zone processing unit 104 described above, the common steering torque T input to the command value calculation unit 105 and the auxiliary torque command value setting unit 51 can be... tb A fourth dead zone processing unit is set up. In this case, Figure 11A In step S4, the determination unit 102 determines whether the steering torque T is satisfied. tb absolute value |T tb | This determination condition is outside the dead zone area of ​​the fourth dead zone processing department.

[0182] Furthermore, in the above embodiment, the angle control unit 54 (refer to...) Figure 4 The system includes a feedforward control unit 63, but this unit can be omitted. In this case, the feedback control torque T calculated by the feedback control unit 62... fb This becomes the basic target torque.

[0183] Furthermore, while the above embodiments illustrate an example of applying the present invention to the motor control of a column-type EPS, the present invention can also be applied to the motor control of EPS other than column-type EPS. Additionally, the present invention can also be applied to the control of electric motors used for steering angle control in steer-by-wire systems.

[0184] The embodiments of the present invention have been described in detail, but these are merely specific examples used to clarify the technical content of the present invention. The present invention should not be limited to these specific examples and its scope is defined only by the appended claims.

[0185] Explanation of reference numerals in the attached figures

[0186] 1...Electric power steering system, 3...Steering wheel, 4...Steering mechanism, 18...Electric motor, 51...Auxiliary torque command value setting unit, 52...Manual steering operation command value calculation unit, 53...Comprehensive angle command value calculation unit, 54...Angle control unit, 55...Torque control unit, 56...Switch, 57...Adder, 61...Low-pass filter (LPF), 62...Feedback control unit, 63...Feedforward control unit, 64...Disturbance torque estimation unit, 65...Torque adder, 66...Disturbance torque compensation unit, 101...High-pass filter, 102...Determination unit, 103...First dead zone processing unit, 104...Second dead zone processing unit, 105...Command value calculation unit.

Claims

1. A motor control device for driving and controlling an electric motor for steering angle control, comprising: The auxiliary torque command value setting unit calculates the auxiliary torque command value using the steering control torque; The manual steering control command value calculation unit calculates the manual steering control command value using the aforementioned steering control torque and the aforementioned auxiliary torque command value; The comprehensive angle command value calculation unit calculates the comprehensive angle command value by adding the automatic steering control command value to the aforementioned manual steering control command value; The control unit performs angle control on the electric motor based on the aforementioned comprehensive angle command value; The dead-zone processing unit is configured for at least one of the input torques when the steering torque input to the manual steering command value calculation unit, the auxiliary torque command value input to the manual steering command value calculation unit, and the steering torque input to the auxiliary torque command value setting unit are set as input torques; and The warning vibration application unit is used to apply a warning vibration torque as a component of the motor torque command value of the aforementioned electric motor. The aforementioned manual steering command value calculation unit is configured to, when a first condition is met, use road information containing information related to the road reaction torque to calculate the manual steering command value; and when the first condition is not met, not use the road information to calculate the manual steering command value. The first condition mentioned above is that at least one of the input torques for which the dead zone processing unit is provided is outside the dead zone range. When the aforementioned warning vibration torque is applied, during a certain period from the moment the state changes from satisfying the first condition to not satisfying the first condition, the manual steering command value calculation unit uses the road surface information to calculate the manual steering command value.

2. The motor control device according to claim 1, wherein, The aforementioned dead zone processing unit includes a first dead zone processing unit that sets the steering torque input to the aforementioned manual steering control command value calculation unit, and a second dead zone processing unit that sets the auxiliary torque command value input to the aforementioned manual steering control command value calculation unit.

3. The motor control device according to claim 1 or 2, wherein, The road surface information mentioned above is calculated based on the comprehensive torque command value and steering angle corresponding to the comprehensive angle command value mentioned above. It is the high-frequency component of the estimated value of the disturbance torque applied to the steering shaft.

4. The motor control device according to claim 1 or 2, wherein, The aforementioned warning vibration application unit is configured to output a vibration torque command value corresponding to the target warning vibration waveform, and the aforementioned vibration torque command value is added to the comprehensive torque command value corresponding to the aforementioned comprehensive angle command value.

5. The motor control device according to claim 1 or 2, wherein, The aforementioned warning vibration application unit is configured to output a vibration angle command value corresponding to the target warning vibration waveform, and the aforementioned vibration angle command value is added to the aforementioned comprehensive angle command value.

Images