JP6492319B2 - Power steering device control device - Google Patents

Description

  The present invention relates to a control device for a power steering device that assists the steering force of a steering wheel.

  Conventionally, in the technique described in Patent Document 1, in a power steering apparatus, steering is performed up to a mechanical maximum steering position (hereinafter referred to as a stroke end position), and an impact caused by suddenly stopping the steering is suppressed. Therefore, the assist torque is reduced toward the stroke end position.

JP 2006-1329 A

In the configuration as in Patent Document 1, the assist torque may not be sufficiently reduced at the stroke end position. Therefore, instead of the stroke end position, it is conceivable to set a control maximum steering position (hereinafter referred to as a software rack stopper position) and reduce the assist torque toward the software rack stopper position. However, when further turning steering is performed from the software rack stopper position toward the stroke end position, the driver may feel uncomfortable if the cutting steering amount differs between the left and right.
The present invention has been made in view of the above problems, and an object of the present invention is to provide a control device for a power steering device that can obtain a stable steering feeling when the left and right cuts are made.

In order to achieve the above object, the control device for a power steering apparatus of the present invention receives a pair of stroke end position signals of a rack bar and receives a steering torque signal which is a signal of information on steering torque generated in the steering mechanism. The stroke end position is set based on the steering torque and the turning angle, and the position offset by a first predetermined amount from one of the pair of stroke end positions to the other stroke end position is set as the one side software rack stopper position. A position offset by the first predetermined amount from the other of the pair of stroke end positions toward the one stroke end position is set as the other side software rack stopper position, and the turning angle is set to the one side software rack stopper position. Is offset by a second predetermined amount toward the other stroke end position. When the steering wheel is steered in the cutting direction, the command signal to the electric motor in the cutting direction is decreased, and the steered wheel is on the stroke end on one side of the other side software rack stopper position. When the steering wheel is steered in the cutting direction beyond the position offset by the third predetermined amount to the position side, the command signal to the electric motor in the cutting direction is decreased, or the electric motor in the switching direction is switched to The stroke end control is performed to increase the command signal.

  In other words, since the software rack stopper position is set based on the stroke end position signal, when the cutting is further performed from the software rack stopper position to the stroke end position, it is possible to suppress a sense of incongruity due to the difference in the amount of cutting between the left and right.

1 is a schematic system diagram illustrating a power steering apparatus according to a first embodiment. FIG. 3 is a control block diagram illustrating a control configuration of the power steering apparatus according to the first embodiment. 3 is a gain map used in stroke end control according to the first embodiment. 3 is a flowchart illustrating a software stroke end position calculation process according to the first embodiment. 12 is a flowchart illustrating a software stroke end position calculation process according to the second embodiment. 12 is a flowchart illustrating software stroke end position calculation processing according to the third embodiment.

[Example 1]
FIG. 1 is a schematic system diagram illustrating a power steering apparatus according to the first embodiment. A steering shaft 2 is connected to the steering wheel 1. A pinion shaft 2b is connected to the end of the steering shaft 2 opposite to the steering wheel 1 via a torsion bar 11a. The pinion shaft 2b has a pinion 2a. A rack and pinion mechanism 3 in which the pinion 2a and the rack teeth 4a mesh with each other is provided at a connection portion between the pinion 2a and the rack housing portion 40 that accommodates the rack bar 4. Thereby, the rotational direction motion of the steering wheel 1 is converted into the axial direction motion, and the steered wheels 30 are steered. The rack housing portion 40 includes a power steering mechanism 5 that assists the axial force of the rack bar 4. The power steering mechanism 5 includes an electric motor 5 a and a gear mechanism 5 b that converts the torque of the electric motor 5 a into an axial force and applies an assist force to the rack bar 4.

  On the steering shaft 2, there is a steering angle sensor 10 that detects a steering angle θ that is a steering wheel steering operation amount of the driver. Between the steering shaft 2 and the pinion shaft 2b, there is a torque sensor 11 that detects the steering torque of the driver based on the amount of twist of the torsion bar 11a. The electric motor 5a has a motor rotation angle sensor 13 that detects the rotation angle of the electric motor 5a. Moreover, it has the vehicle speed sensor 12 which detects vehicle speed VSP. The control device 20 includes a receiving unit that receives signals from the steering angle sensor 10, the torque sensor 11, the vehicle speed sensor 12, and the motor rotation angle sensor 13. The control device 20 controls the current of the electric motor 5a based on various signals, and applies an optimal assist force.

FIG. 2 is a control block diagram illustrating a control configuration of the power steering apparatus according to the first embodiment.
The torque calculation unit 201 calculates the driver's steering torque Ts based on the detection signal of the torque sensor 11. The assist calculation unit 202 calculates a reference assist torque Tas based on the steering torque Ts and outputs it to the addition unit 209. The phase compensation calculation unit 203 calculates a phase compensation torque Tx that compensates for a phase difference generated by the low-rigidity torsion bar 11 a built in the torque sensor 11 and suppresses vibration of the system, and outputs it to the addition unit 209. A steering angle calculation unit 204 calculates a steering angle θs that is an operation amount of the steering wheel 1 based on a detection signal of the steering angle sensor 10. The steering speed calculation unit 205 calculates the steering speed Δθs of the steering wheel 1 based on the detection signal of the steering angle sensor 10. The damping torque calculation unit 206 calculates a damping torque Td that gives a viscous resistance that improves the convergence and stability of the vehicle based on the steering speed Δθs, and outputs it to the addition unit 209.

  The software rack stopper position setting unit 207 includes a signal receiving unit 2071 that receives the steering torque Ts, the vehicle speed VSP, and the steering angle θs, a stroke end position setting unit 207a that sets a physical stroke end position, and a set stroke end. A stroke end position signal receiving unit 2072 for receiving the position. The stroke end position setting unit 207a includes a reference value information storage unit that stores a stroke end reference value θrealend_default corresponding to a preset physical stroke end position. The software rack stopper position setting unit 207 calculates the right software rack stopper position θRend and the left software rack stopper position θLend, which are stroke end positions for control, based on the steering torque Ts, the vehicle speed VSP, and the steering angle θs. To do. Details of this calculation will be described later. Both the right software rack stopper position θRend and the left software rack stopper position θLend are collectively referred to as the software rack stopper position θend, and both the right stroke end position θRrealend and the left stroke end position θLrealend are collectively referred to as strokes. Also described as an end position θrealend.

  The stroke end control unit 208 reduces the assist torque from the control start position θR or θL toward the software rack stopper position θend based on the software rack stopper position θend, the vehicle speed VSP, and the steering angle θs. A stroke end control torque Tend that increases the assist torque so as to become the normal assist torque from the stopper position θend toward the control start position θR or θL is calculated.

  FIG. 3 is a gain map used in the stroke end control of the first embodiment. A steering angle θ is set on the horizontal axis, and a gain is set on the vertical axis. On the horizontal axis, the right software rack stopper position θRend offset from the right stroke end position θRrealend to the left software rack stopper position θLend by a predetermined deviation angle θx is set. Further, a right control start value θR that is offset from the right software rack stopper position θRend to the left software rack stopper position θLend by a predetermined amount θ1 is set. Similarly, the left software rack stopper position θLend offset from the left stroke end position θLrealend to the right software rack stopper position θRend by a predetermined deviation angle θx is set on the horizontal axis. Further, a left control start value θL that is offset from the left software rack stopper position θLend by a predetermined amount θ1 to the right software rack stopper position θRend is set. The neutral position of the steering angle θ exists between θL and θR. Within this range, the gain is 0 and no particular control is performed. On the other hand, when the steering angle θ exceeds θR and approaches θRend, the gain gradually increases. Similarly, when the steering angle θ exceeds θL and approaches θLend, the gain gradually increases. When a large gain is output, the stroke end control torque Tend is output as a negative value having a large absolute value, and the final assist torque becomes small. Even if the driver further cuts the steering wheel 1 from the software rack stopper position θend to the stroke end position θrealend, the assist torque is continuously limited.

  This stroke end control torque Tend informs the driver that it is in the vicinity of the stroke end in a pseudo manner, and avoids collision with the physical stroke end position with a strong impact. As shown in FIG. 3, in the stroke end control, the control region is set based on the stroke end position θrealend, regardless of the neutral position of the steering. Therefore, when the neutral position is shifted due to an assembly error or alignment. Even if it exists, stroke end control can be implemented without being influenced by the neutral position. Therefore, the amount of steering between the stroke end control and the physical stroke end does not fluctuate greatly, and the uncomfortable feeling given to the driver can be suppressed.

  The stroke end control unit 208 calculates the stroke end control torque Tend and outputs it to the addition unit 209. The motor torque command calculation unit 210 determines a current value to be commanded to the electric motor 5a based on the assist torque T finally calculated from various torque commands, and outputs it to the electric motor 5a.

FIG. 4 is a flowchart illustrating software stroke end position calculation processing according to the first embodiment.
In step S1, it is determined whether or not the set value of the software rack stopper position θend is an effective value. If the software rack stopper position θend is an effective value, this control flow is terminated. If not, the process proceeds to step S2. Whether or not it is an effective value represents, for example, whether or not it is within a predetermined range away from a stroke end reference value θrealend_default corresponding to a preset physical stroke end position. If it is within the predetermined range, the software rack stopper position θend is Judged to be a valid value.
In step S2, it is determined whether or not the steering torque Ts is greater than or equal to a predetermined value T0. If the steering torque Ts is greater than or equal to the predetermined value T0, the process proceeds to step S3. Otherwise, the control flow ends. The predetermined value T0 is set on the basis of a steering torque larger than the normal time generated when steering to the stroke end position θrealend.
In step S3, it is determined whether or not the steering angle θs is equal to or greater than a predetermined value θ0. When the steering angle θs is equal to or greater than the predetermined value θ0, the process proceeds to step S4, and otherwise, the control flow ends. The predetermined value θ0 is a value set at a position slightly closer to the neutral position than the stroke end reference value θrealend_default, and is a value with which it can be confirmed that the stroke end position θrealend is almost reached.

In step S4, it is determined whether or not the vehicle speed VSP is equal to or lower than a predetermined value VSP0. When the vehicle speed VSP is equal to or lower than the predetermined value VSP0, the process proceeds to step S5, and otherwise, the control flow ends. The predetermined value VSP0 is a predetermined value representing a normal running state, unlike when entering a garage. In other words, if the vehicle speed is equal to or higher than VSP0, it is not considered that the vehicle is steered to the stroke end position. Therefore, if the vehicle speed is equal to or higher than the predetermined value VSP0, the present control flow is terminated.
In step S5, it is determined whether or not the steering angle θs is constant for a predetermined time. If it is constant, the process proceeds to step S6. Otherwise, the control flow ends. This is because, if the steering angle θs is continuously constant for a predetermined time, it is considered that the steering angle θs has been in contact with the stroke end position.

In step S6, the software rack stopper position θend is set. Specifically, it is determined that the current steering angle θs corresponds to the stroke end position, and θrealend = current steering angle θs is set. Then, the software rack stopper position θend that is offset from the θrealend to the neutral position side by a predetermined deviation angle θx is set.
In step S7, a preset full stroke amount θmax is subtracted or added from the set θend, and the other software rack stopper position θend is set. For example, when the right software rack stopper position θRend is calculated, θmax is subtracted from θRrealend to calculate the left stroke end position θLrealend, and a predetermined deviation angle θx is added to θLrealend to set the left software rack stopper position θLend ( (See FIG. 3). On the other hand, when the left software rack stopper position θLend is calculated, θmax is added to θLrealend to calculate the right stroke end position θRrealend, and a predetermined deviation angle θx is subtracted from θRrealend to set the right software rack stopper position θRend ( (See FIG. 3). As a result, when one software rack stopper position θend is set, both software rack stopper positions θend can be set, and there is no need to detect both stroke end positions θrealend.

[Effect of Example 1]
Hereinafter, in Example 1, the following effects are obtained.
(1-1) Steering wheels are steered by moving in the axial direction with rotation of the pinion shaft 2b ( pinion shaft) having a pinion 2a rotating with the steering operation of the steering wheel 1 and the pinion shaft 2b. A control device for a power steering apparatus, comprising: a rack and pinion mechanism (steering mechanism) having a rack bar 4 to be driven; and an electric motor 5a that applies a steering force to the rack bar 4 (steering mechanism).
A motor torque command calculation unit 210 that calculates a command signal for driving the electric motor 5a according to the operation state of the steering wheel 1 and a steering angle θs (steering angle signal) that is a signal indicating the turning angle of the steered wheels 30 are received. A signal receiving unit 2071 (steering angle signal receiving unit),
A stroke end position signal receiving unit 2072 for receiving a stroke end position signal θrealend which is a signal related to a pair of stroke end positions of the rack bar 4;
A position offset by a predetermined divergence angle θx (first predetermined amount) from one of the pair of stroke end positions to the other stroke end position is set as the one-side software rack stopper position. A software rack stopper position setting unit 207 that sets a position offset by a predetermined deviation angle θx to the stroke end position side as a software rack stopper position on the other side;
When the steering angle θs is equal to or greater than a position offset by a predetermined amount θ1 (second predetermined amount) from the one side software rack stopper position to the other stroke end position side, the steering wheel 1 is steered in the cutting direction. The command signal to the electric motor 5a in the direction is decreased, and the steered wheel 30 is not less than a position offset by a predetermined amount θ1 (third predetermined amount) toward the stroke end position on one side from the other side software rack stopper position. When the steering wheel 1 is steered in the cutting direction, a command signal to the electric motor 5a in the cutting direction is commanded so that the torque of the electric motor 5a is reduced, or the electric motor 5a in the switching direction is supplied to the electric motor 5a. Stroke end control that instructs the command signal to increase the torque of the electric motor 5a. And Kuendo control unit 208,
A control device for a power steering apparatus, comprising:
In other words, since the software rack stopper position θend is set based on the stroke end position signal, when the cutting is further performed from the software rack stopper position θend to the stroke end position θrealend, the uncomfortable feeling due to the difference in the cutting amount on the left and right is suppressed. Can do.

  In the first embodiment, the steering angle θs is calculated based on the detection signal of the steering angle sensor 10, but the turning angle is detected from the motor rotation angle sensor 13, and the steering angle is estimated based on the turning angle. There may be. In the first embodiment, the software rack stopper position setting unit 207 is provided with a stroke end position setting unit 207a, and further includes a stroke end position signal receiving unit 2072 that receives the set stroke end position. The configuration may be such that the stroke end position is calculated from the steering torque Ts, the steering angle θs, the vehicle speed VSP, the motor rotation angle, etc., outside the software rack stopper position setting unit 207, and the calculation result is received. . In the first embodiment, the right control start value θR and the left control start value θL are each offset by a predetermined amount θ1 from the software rack stopper position, but different predetermined amounts may be set on the left and right.

(1-2) The control device according to (1-1) described above includes a signal receiving unit 2071 (torque signal receiving unit) that receives a steering torque Ts (steering torque that is a signal of information on steering torque generated in the steering mechanism). And a stroke end position setting unit 207a that sets a stroke end position based on the steering torque Ts and outputs the stroke end position signal to the stroke end position signal receiving unit 2072.
Specifically, as shown in step S2, when further infeed steering is performed at the stroke end position, the operator detects the stroke end position by utilizing the fact that the steering torque is increased compared to that during normal steering, so that the operator can It is not necessary to set the stroke end position while checking the end position.

(1-3) In the control device for a power steering device according to (1-2),
The stroke end position setting unit 207a sets the stroke end position based on the steering torque Ts and the steering angle θs.
Specifically, as shown in step S3, more accurate stroke end is determined by determining whether or not the steering angle θs is approximately equal to or greater than θ0 representing the stroke end position and setting the stroke end position. The position can be set.

(1-4) In the control device for a power steering device according to (1-3) above,
The stroke end position setting unit 207a sets the steering angle θs as the stroke end position θrealend when the steering torque Ts is equal to or greater than the predetermined value T0 and the change amount of the steering angle θs is equal to or less than the predetermined value after a predetermined time has elapsed. A featured power steering device.
Specifically, as shown in steps S2 and S5, when further turning steering is performed at the stroke end position, the stroke end position is utilized by utilizing the fact that the steering torque increases compared to that during normal steering and the turning angle does not change. By detecting this, a more accurate stroke end position can be detected.

(1-5) The control device for a power steering apparatus according to (1-2) includes a signal reception unit 2071 (vehicle speed signal reception unit) that receives a vehicle speed signal VSP that is a signal of vehicle speed information,
The stroke end position setting unit 207a sets a steering angle θs when the steering torque Ts is equal to or higher than a predetermined value T0 and the vehicle speed VSP is equal to or lower than the predetermined value VSP0 as the stroke end position θrealend, .
Specifically, as shown in steps S2 and S4, since the possibility of steering operation to the stroke end position is low when the vehicle speed VSP is more than a certain level, the vehicle speed is low, such as garage entry. By setting this as the stroke end position setting condition, the stroke end position can be detected more accurately.

(1-6) The control device for a power steering apparatus according to (1-1) above is based on the angle between one pair of stroke end positions θRrealend and θLrealend and information on one stroke end position, and the other stroke end A control apparatus for a power steering apparatus, comprising a stroke end position setting unit 207a for estimating a position.
Specifically, as shown in step S7, if there is two pieces of information, one stroke end position information and angle information between both stroke end positions, the other stroke end position can be estimated. There is no need to detect both stroke end positions, and the software rack stopper position can be set quickly.

(1-7) The power steering apparatus control device according to (1-1) includes a stroke end position setting unit 207a that sets the stroke end position θrealend and outputs the stroke end position θrealend to the stroke end position signal receiving unit 2072.
The stroke end position setting unit 207a updates the stroke end position θrealend a plurality of times.
The stroke end position θrealend can change due to deterioration of a rubber stopper provided at the stroke end position θrealend, change in alignment, tire and wheel replacement, loss of memory information due to battery replacement, and the like. On the other hand, by updating the stroke end position information θrealend, the stroke end control can be performed based on the appropriate stroke end position information.

(1-12) In the control device for a power steering device according to (1-1),
When the steering wheel 1 is steered in the cutting direction, the stroke end control unit 208 is configured so that the assist torque of the electric motor 5a in the cutting direction decreases as the steering angle θs approaches the software rack stopper position θend. Alternatively, the control device for the power steering apparatus is characterized in that the command signal to the electric motor 5a is variably controlled so that the assist torque of the electric motor 5a in the switchback direction increases.
Specifically, as shown in the gain map of FIG. 3, by repeatedly controlling the command signal to the electric motor 5a so that the maximum turning angle during normal steering becomes the software rack stopper position θend, the repeated stroke end is achieved. It is possible to suppress a decrease in the durability of the device due to the steering operation to the position θrealend.

[Example 2]
Next, Example 2 will be described. Since the basic configuration is the same as that of the first embodiment, only different points will be described. FIG. 5 is a flowchart illustrating the software stroke end position calculation process according to the second embodiment.
In steps S21 to S22, as in steps S2 to S4 of the first embodiment, it is determined whether or not the stroke end position has been reached based on various sensor signals. move on.
In step S23, it is determined whether or not the stroke end control is being executed. If it is not being executed, this control flow is terminated. On the other hand, when it is being executed, the process proceeds to step S24 while continuing the stroke end control based on the previously set stroke end position θrealend.

  In step S24, the current software rack stopper position θend_current is calculated. Specifically, it is determined that the current steering angle θs corresponds to the stroke end position, and the current stroke end position θrealend_current = current steering angle θs is set. Then, it is calculated as the software rack stopper position θend_current that is offset from θrealend_current to the neutral position side by a predetermined deviation angle θx. At this time, the software rack stopper position θend_current is not yet updated as a new software rack stopper position θend.

  In step S25, it is determined whether or not the absolute value of the difference between the stroke end reference value θrealend_default and the current stroke end position θrealend_current is smaller than a predetermined angle θz. Proceed to On the other hand, when the angle is larger than the predetermined angle θz, the condition of steps S21 to S22 is satisfied even though it is not the stroke end position because the steered wheel 30 is stuck in the side groove or is in contact with the step. There is a possibility. Therefore, in this case, this control flow is terminated, and the software rack stopper position θend is not updated.

  In step S26, it is determined whether or not the current stroke end position θrealend_current is larger than the currently set stroke end position θrealend, in other words, whether the position is farther from the neutral position. If larger, the process proceeds to step S27. Then, the current stroke end position θrealend_current is set and updated as the stroke end position θrealend, and the current software rack stopper position θend_current calculated based on the stroke end position θrealend_current is updated as a new software rack stopper position θend. On the other hand, when the current stroke end position θrealend_current is smaller than the currently set stroke end position θrealend, the software rack stopper position θend is not updated. It is assumed that the steering torque Ts near the software rack stopper position is increased by the stroke end control, and a position before the actual stroke end position is erroneously recognized as the stroke end position. At this time, if the software rack stopper position is updated based on the stroke end position misidentified as the position on the neutral position side than the actual position, the software rack stopper position θend gradually shifts to the neutral position side and can be steered. This is to prevent an unnecessary area from being narrowed unnecessarily.

As described above, in the second embodiment, the following functions and effects can be obtained in addition to the functions and effects of the first embodiment.
(2-8) In the control device for a power steering device according to (1-7) above,
The stroke end control unit 208 performs the stroke end control based on the previous value θrealend of the stroke end position when the stroke end position setting unit 207a updates the stroke end position θend. apparatus.
Specifically, as shown in step S23, the stroke end control can be performed even when the stroke end position θrealend is being updated.

(2-9) In the control device for a power steering device according to (1-7) above,
The stroke end position setting unit 207a includes a reference value information storage unit that stores information of a stroke end reference value θrealend_default that is a reference value of the stroke end position, and the stroke end reference value θrealend_default and the current value θrealend_current to be updated When the difference between the two values is equal to or greater than a predetermined value θz, the control device for the power steering apparatus is not updated to the current value θrealend_current.
Specifically, as shown in step S25, when the difference between the stroke end position reference value θrealend_default and the current value θrealend_current is greater than or equal to a predetermined value, the wheel 30 is not at the stroke end position because the steered wheels 30 are fitted in the side grooves. Nevertheless, since there is a possibility that the condition of the stroke end position is satisfied, in such a case, updating to an incorrect value can be suppressed by not updating to the current value.

(2-10) In the control device for a power steering device according to (1-7) above,
The stroke end position setting unit 207a employs, as the new stroke end position, a value farther from the neutral position among the current value θrealend_current scheduled to be updated as the stroke end position and the previous value θrealend which is the previous value of the current value. A control device for a power steering device.
Specifically, as shown in step S26, the steering rack torque is increased by the software rack stopper, and the software rack stopper position θend is gradually shifted to the neutral position side by misidentifying the software rack stopper position θend as the stroke end position θrealend. Can be prevented.

Example 3
Next, Example 3 will be described. Since the basic configuration is the same as that of the second embodiment, only different points will be described. FIG. 6 is a flowchart illustrating a software stroke end position calculation process according to the third embodiment. In the second embodiment, the software rack stopper position θend_current newly calculated in step S27 is updated as the software rack stopper position θend. In contrast, in the third embodiment, in step S271, a value that is offset from the newly calculated software rack stopper position θend_current to the neutral position side by a predetermined value θp is set as a new software rack stopper position θend. As a result, when updating to the current value larger than the previous value in step S26, even if the larger stroke end position θrealend is erroneously recognized, the value can be gradually returned to the normal value by repeating the value update. it can.

As described above, in the third embodiment, the following operational effects can be obtained in addition to the operational effects of the first and second embodiments.
(3-11) In the control device for a power steering device according to (2-10),
The stroke end position setting unit 207a adopts a value offset from the larger one of the current value θend and the previous value θend_current to the neutral position side by a predetermined value θp as a new software rack stopper position θend (stroke end position). A control device for a power steering device.
Specifically, as shown in step S271, even if a value larger than the actual stroke end position is erroneously recognized as the stroke end position, the value is gradually returned to the normal value by repeatedly updating the value. Can do.

DESCRIPTION OF SYMBOLS 1 Steering wheel 2 Steering shaft 2a Pinion 2b Pinion shaft 3 Rack & pinion mechanism 4 Rack bar 4a Rack tooth 5 Power steering mechanism 5a Electric motor 10 Steering angle sensor 11 Torque sensor 11a Torsion bar 12 Vehicle speed sensor 13 Motor rotation angle sensor 20 Control device 30 Steering wheel 40 Rack receiving part
207 Software rack stopper position setting section
207a Stroke end position setting section
208 Stroke end controller
209 Adder
210 Motor torque command calculator
2071 Signal receiver
2072 Stroke end position signal receiver

Claims (4)

A pinion shaft which rotates with the steering operation of the steering wheel, a steering mechanism having a rack bar to steer the steered wheels by with axial movement to a rotation of the pinion shaft and meshing said pinion shaft, the steering mechanism An electric motor for applying a steering force to the power steering device control device,
A motor command signal calculation unit for calculating a command signal for driving the electric motor in accordance with an operation state of the steering wheel;
A steering angle signal receiving unit that receives a steering angle signal that is a signal indicating the steering angle of the steered wheels;
A stroke end position signal receiving unit that receives a stroke end position signal that is a signal related to a pair of stroke end positions of the rack bar;
A torque signal receiving unit that receives a steering torque signal that is a signal of information on steering torque generated in the steering mechanism;
A stroke end position setting unit that sets the stroke end position based on the steering torque and the turning angle and outputs the stroke end position signal to the receiving unit;
A position that is offset by a first predetermined amount from one of the pair of stroke end positions to the other stroke end position is set as one side software rack stopper position, and one stroke from the other of the pair of stroke end positions is set. A software rack stopper position setting unit for setting the position offset by the first predetermined amount to the end position side as the other side software rack stopper position;
When the steering angle is equal to or greater than a position offset by a second predetermined amount from the one side software rack stopper position to the other stroke end position side and the steering wheel is steered in the cutting direction, the steering direction is changed to the cutting direction. And the steering wheel is cut at a position equal to or greater than a position where the steered wheel is offset by a third predetermined amount toward the stroke end position on one side of the other side software rack stopper position. When the steering operation is performed in the direction, the command signal to the electric motor in the cutting direction is output so that the torque of the electric motor decreases, or the command signal to the electric motor in the switch back direction is output to the electric motor. A straw for stroke end control that outputs so that the torque of the motor increases. And end the control unit,
A control device for a power steering apparatus, comprising: A control device for a power steering device according to claim 1,
The stroke end position setting unit sets, as the stroke end position, the turning angle when the steering torque is equal to or greater than a predetermined value and the change amount of the turning angle is equal to or less than a predetermined value after a predetermined time has elapsed. A power steering device. A control device for a power steering device according to claim 1,
The stroke end position setting unit updates the stroke end position a plurality of times. A control device for a power steering device according to claim 1,
The stroke end control unit is configured such that when the steering wheel is steered in the cutting direction, the assist torque of the electric motor in the cutting direction decreases as the turning angle approaches the software rack stopper position. Or a control device for the power steering device, wherein the command signal to the electric motor is variably controlled so that the assist torque of the electric motor in the switchback direction increases.

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