JP6313703B2 - Electric power steering device - Google Patents

Description

  The present invention relates to an electric power steering device applied to, for example, an automobile.

  As a conventional electric power steering device, for example, those described in the following patent documents are known.

  In other words, in the electric power steering device described in this patent document, the contact noise of the rack stopper when reaching the rack end is reduced by reducing and correcting the steering assist torque when it is near the rack end.

JP 2008-290525 A

  However, in the case of the conventional electric power steering device, since the steering assist torque reduction correction is performed based on the steering speed, the steering assist torque reduction correction is completed when further cutting is performed after the steering speed is converged. As a result, a normal steering assist torque is generated, which may cause a sense of incongruity in steering.

  The present invention has been devised in view of such technical problems, and an object of the present invention is to provide an electric power steering device for reducing the collision with the rack stopper while suppressing the uncomfortable feeling of steering.

  In particular, the present invention includes a steering torque signal receiving unit that receives a steering torque signal, a steering angle signal receiving unit that receives a steering angle signal, a steering angular velocity signal receiving unit that receives a steering speed signal, and the steering torque signal. A basic assist signal calculation unit that calculates a basic assist signal that is a basic command signal to the electric motor, and when the steering angle signal is equal to or greater than a predetermined angle and the steering wheel is steered in the cutting direction, A first correction amount calculation unit for calculating a first correction amount that increases as the rudder angle signal increases and acts in a direction opposite to the cutting direction; and the rudder angle signal is equal to or greater than a predetermined angle. When the steering wheel is steered in the cutting direction, a second correction amount that increases with an increase in the rudder angular velocity signal and acts in a direction opposite to the cutting direction. And a motor command signal output unit that outputs a command signal to the electric motor based on the basic assist command signal, the first correction amount, and the second correction amount. It is characterized by.

  By applying the spring reaction force generated by the first correction amount, even when the rudder is further cut after the rudder angular speed is converged, the cut reaction steering can be suppressed by the spring reaction force. Occurrence of discomfort can be suppressed.

  Further, in addition to the spring reaction force based on the first correction amount, by applying the damping force generated by the second correction amount, it becomes possible to suppress a rapid decrease in the steering load by the damping force, This is used to effectively suppress the steering discomfort.

1 is a system configuration diagram of an electric power steering apparatus according to the present invention. FIG. 2 is a control block diagram according to the first and second correction amount calculation units of the control unit shown in FIG. 1 according to the first embodiment of the present invention. 3 is a flowchart relating to calculation of first and second correction signals shown in FIG. 2. 4 is a map used for the calculation in step S108 shown in FIG. It is another map used for the calculation of step S108 shown in FIG. It is another map used for the calculation of step S108 shown in FIG. FIG. 4 is a map used for the calculation in step S109 shown in FIG. It is another map used for the calculation of step S109 shown in FIG. It is another map used for the calculation of step S109 shown in FIG. FIG. 4 is a control block diagram according to a second embodiment of the present invention and related to correction control of steering assist torque of the control unit shown in FIG. 1. 11 is a flowchart according to steering assist torque correction control shown in FIG. 10.

Hereinafter, embodiments of an electric power steering apparatus according to the present invention will be described with reference to the drawings. In the following embodiments, an example in which the electric power steering apparatus according to the present invention is applied to an electric power steering apparatus for an automobile as in the conventional case will be described.

  FIG. 1 is a schematic diagram of an apparatus for explaining an outline of a system configuration of an electric power steering apparatus according to the present invention.

  The electric power steering apparatus shown in the figure has an input shaft 1 as a first shaft that is linked to the steering wheel SW so that one end of the electric power steering device can be integrally rotated, and one end is connected to the other end of the input shaft 1 via a torsion bar (not shown). Relative rotational displacement between the output shaft 2 as the second shaft, which is connected so as to be relatively rotatable, and whose other end is linked to the steered wheels WL and WR via the rack and pinion mechanism RP, and the input shaft 1 and the output shaft 2 A motor unit MU for applying a steering assist torque corresponding to the driver's steering torque to a rack bar 3 to be described later based on detection results of a torque sensor TS for detecting the steering torque from the vehicle and a vehicle speed sensor (not shown), and the motor unit MU The transmission mechanism RG mainly converts the output (rotational force) of the rack shaft 3 to be described later and transmits it to the axial direction moving force of the rack shaft 3 while reducing the output (rotational force). The input shaft 1, the output shaft 2, and the rack and pinion mechanism RP constitute a steering mechanism of the present invention.

  The rack and pinion mechanism RP includes rack teeth 3a formed in a predetermined axial direction range of a rod-shaped rack bar 3 arranged in a shape substantially orthogonal to the pinion teeth 2a formed on the outer periphery of one end of the output shaft 2. And the rack bar 3 moves in the axial direction in accordance with the rotation direction of the output shaft 2. Both ends of the rack bar 3 are linked to the steered wheels WR and WL via tie rods 4 and 4 and knuckle arms (not shown), respectively. The tie rods 4 and 4 are moved along the axial movement of the rack bar 3. By pulling a knuckle arm (not shown) through the wheel, the directions of the steered wheels WR and WL are changed. At this time, rack ends (not shown) are provided at both ends of the rack bar 3 so as to be larger than the inner diameters of the openings at both ends of the rack housing HG. Each end face constitutes a so-called rack stopper, and the rack end on the opposite side of the movement direction of the rack bar 3 comes into contact with the end face of the rack housing HG so that further axial movement of the rack bar 3 is restricted. It has become. In addition, bushes as cushioning materials are interposed in the contact portions of the rack ends, and the contact between the end portions of the rack end and the end surfaces of the rack housing HG is buffered by the bushes. It is like that.

  The motor unit MU is attached to the other end side of the electric motor 7 that applies steering assist torque to the rack bar 3 via the transmission mechanism RG by rotationally driving an input pulley 5 described later. The electronic control unit 8 serving as a control device that drives and controls the electric motor 7 in accordance with predetermined parameters such as steering torque and vehicle speed is integrally configured.

  The transmission mechanism RG is provided on the outer peripheral side of the motor output shaft 7a of the electric motor 7 so as to be integrally rotatable. An output pulley 6 provided so as to be relatively rotatable and rotating about the axis L2 of the rack bar 3 based on the rotational force of the input pulley 5, and interposed between the output pulley 6 and the rack bar 3, The ball screw mechanism (not shown) that converts the rotation of the rack bar 3 into the axial motion while decelerating the rotation of the input pulley 5 is wound around the pulleys 5 and 6, and the rotation of the input pulley 5 is transferred to the output pulley 6. And a belt 9 that is used for synchronous rotation of the pulleys 5 and 6.

[First Embodiment]
FIG. 2 is a control block diagram for steering assist torque correction control according to the first embodiment of the present invention.

  As shown in the figure, the electronic control unit 8 receives a steering torque signal receiver 10a that receives a steering torque signal Ts detected by the torque sensor TS, and a steering angle signal θs detected by a steering angle sensor not shown. And a rudder angle signal receiving unit 10b.

  Based on the steering torque signal Ts, a basic assist signal Ib that is a base of the steering assist torque is calculated by the basic assist signal calculation unit 11, and a phase with respect to the steering torque signal Ts is calculated by the phase compensation calculation unit 12. A phase compensation signal It for use in compensation is calculated.

  On the other hand, the steering angle signal θs is differentially calculated by the steering angle speed calculation unit 13 based on the steering angle signal θs to calculate the steering angle speed signal ωs, and the damping processing unit 14 based on the steering angle speed signal ωs. A damping processing signal Id for changing the steering assist control characteristic is output according to ωs.

  The steering assist signal Ia corresponding to the basic assist command signal of the present invention is calculated by adding the basic assist signal Ib, the phase compensation signal It and the damping processing signal Id thus calculated in the steering assist signal calculation unit 15. The

  A first correction signal D1 (corresponding to a first correction amount of the present invention) used for generating a spring reaction force is calculated by the first correction signal calculation unit 21 based on the steering angle signal θs and the rudder angle signal θs. Based on the angular velocity signal ωs, the second correction signal calculation unit 22 calculates a second correction signal D2 (corresponding to the second correction amount of the present invention) used to generate damping force, and corrects both the correction signals D1 and D2. By adding in the signal calculation unit 23, the correction control signal Dx is calculated.

  As will be described later, the first correction signal D1 is obtained when the steering angle signal θs is greater than or equal to a predetermined angle (a predetermined value Xs described later) and the steering wheel is steered in the turning direction. The angle signal θs increases as the angle signal θs increases, and acts in the direction opposite to the cutting direction.

  On the other hand, as will be described later, the second correction signal D2 is obtained when the steering angle signal θs is greater than or equal to a predetermined angle (predetermined value Xs described later) and the steering wheel is steered in the turning direction. It increases as the angular velocity signal ωs increases, and acts in the direction opposite to the cutting direction.

  Then, the motor command signal output unit 16 adds the steering assist signal Ia and the correction control signal Dx, thereby giving the steering assist signal Ia to the correction control signal Dx (first and second) for the electric motor 7. The corrected command signal corrected by the correction signals D1, D2) is output as the motor command signal Io.

  Thus, with respect to the basic assist signal Ib used for steering assistance in the cutting direction, a force in the direction opposite to the cutting direction (spring reaction force, damping force) based on the first and second correction signals D1 and D2. ) Is attenuated, the steering torque in the cutting direction is attenuated, and the collision with the rack stopper can be suppressed.

  Note that the sum of the correction signals D1 and D2 of the first and second correction signals D1 and D2 is larger than the basic assist signal Ib. By adopting such a configuration, it is possible to exert a sufficient damping action even when the steering operation is abrupt in the cutting direction.

  Further, in the first correction signal calculation unit 21, when the steering angle signal θs is equal to or greater than a predetermined value Xs described later and the steering wheel is steered in the reversing direction opposite to the cutting direction, the steering angle The first correction signal D1 may be calculated so as to increase as the signal θs increases and to act in the switchback direction.

  Similarly, also in the second correction signal calculation unit 22, when the steering angle signal θs is equal to or greater than a predetermined value Xs to be described later and the steering wheel is steered in a reversing direction opposite to the cutting direction, The second correction signal D2 may be calculated so as to increase as the steering angle signal θs increases and to act in the cutting direction.

  Further, in the second correction signal calculation unit 22, when the steering angle signal θs is equal to or greater than a predetermined value Xs described later and the steering wheel is steered in a reversing direction opposite to the cutting direction, the rudder is steered. The second correction signal D2 may be calculated so as to increase as the angle signal θs increases and to act in the switchback direction.

  FIG. 3 is a flowchart relating to the calculation of the first and second correction signals D1 and D2 in the first and second correction signal calculation units 21 and 22.

  As shown in the figure, first, the steering angle signal θs detected by the steering angle sensor is read (step S101). Subsequently, the steering angular velocity signal ωs is calculated based on the read steering angle signal θs (step S102). And the code | symbol Sg of the steering angle signal (theta) s showing a steering direction is preserve | saved (step S103).

  Next, it is determined whether or not the absolute value | θs | of the steering angle signal θs read earlier is equal to or greater than a predetermined value Xs corresponding to the predetermined angle of the present invention (step S104). By outputting the correction control signal Dx as zero, this program is terminated. (Step S105).

  On the other hand, if it is determined Yes in step S104, the difference Δθs between the absolute value | θs | of the steering angle signal θs and the predetermined value Xs is calculated (step S106), and then the difference Δθs is calculated as shown in FIG. A first correction signal D1 that is a spring reaction force Fs is obtained by referring to a predetermined map as shown in FIG. 6 (step S107). In obtaining the first correction signal D1, it is also possible to calculate by multiplying the difference Δθs by a predetermined gain Gs (D1 = Δθs × Gs × Sg).

  Here, the maps shown in FIGS. 4 to 6 take the steering angle on the horizontal axis and the spring reaction force Fs on the vertical axis. In the map shown in FIG. 4, the spring reaction force Fs increases linearly. In the map shown, the spring reaction force Fs increases in a quadratic curve convex upward, and in the map shown in FIG. 6, the spring reaction force Fs increases in a quadratic curve convex downward. Each is shown (D1 = Fs × Sg).

  Subsequently, with respect to the difference Δθs, a damping force gain Gd is calculated by referring to a predetermined map as shown in FIGS. 7 to 9 (step S108), and then the steering angular velocity ωs is multiplied by the damping force gain Gd. Thus, the second correction signal D2 that is the damping force Fd (= Gd × ωs) is calculated (step S109). The damping force gain Gd can be obtained by, for example, calculation in addition to the map reference.

  Here, the maps shown in FIGS. 7 to 9 have the steering angle on the horizontal axis and the damping force gain Gd on the vertical axis. In the map shown in FIG. 7, the damping force gain Gd increases linearly, as shown in FIG. The map shows that the damping force gain Gd increases like a quadratic curve with a convex upward, and the map shown in FIG. 9 shows that the damping force gain Gd increases like a quadratic curve with a convex downward. Yes. In each of the maps shown in FIGS. 7 to 9, when the steering angle θs reaches the predetermined value Xs that is a threshold value, the predetermined amount Kd is set as the damping force gain Gd, so that the steering speed is particularly high. However, a sufficient damping effect can be obtained.

  The first and second correction signals D1 and D2 obtained in this way are integrated, and the result is output as the correction control signal Dx (step S110), thereby ending this program.

  From the above, according to the electric power steering apparatus according to the present embodiment, a control stopper by reverse assist is provided in front of the physical rack stopper, and the steering angle θs is the predetermined value that is the control stopper. When Xs is reached, the amount of the torque exceeding the predetermined value Xs, that is, the spring reaction force Fs generated by the first correction signal D1 is applied to the difference Δθs to further steer after the steering angular velocity ωs converges. Even in the case of cutting, it becomes possible to suppress the cutting steering by the spring reaction force Fs, and it is possible to suppress the occurrence of the steering discomfort.

  As described above, the spring reaction force Fs can be applied to the steering in the return direction that is opposite to the infeed direction in the return direction. In the case of such a configuration, there is an advantage that the turning back of the rudder can be promoted by the spring reaction force Fs.

  In the electric power steering apparatus, in addition to the spring reaction force Fs, the damping force Fd generated by the second correction signal D2 is applied to the incision steering so that the steering load is reduced by the damping force Fd. This makes it possible to suppress a sudden decrease, and to effectively suppress the uncomfortable steering feeling.

  As described above, the damping force Fd can also be applied to steering in the switchback direction that is opposite to the cutting direction. That is, when the damping force Fd is applied in the cutting direction opposite to the switching back direction with respect to the steering in the switching back direction, the spring reaction force Fs has the damping force Fd applied in the cutting direction. This has the merit of suppressing the problem that the rudder is rebounded back in the switchback direction.

  Further, as described above, the damping force Fd can be applied to the steering in the switchback direction in the switchback direction. With such a configuration, there is an advantage that the steering operation in the rudder return direction can be smoothly performed with the damping force Fd acting in the reverting direction.

  Further, the second correction signal calculation unit 22 is configured to calculate the second correction signal D2 so as to change in accordance with the change of the steering angle signal θs, so that the adjustment range of the damping force with respect to the steering angle signal θs can be increased. As a result, it is possible to more effectively suppress a collision with the rack stopper.

  In particular, in the present embodiment, the second correction signal D2 increases as the steering angle signal θs increases, so that convergence to the control pseudo stopper by the correction is promoted. A collision with the stopper can be more effectively suppressed.

  In the present embodiment, the second correction signal calculation unit 22 does not multiply the steering speed signal ωs by the gain Gd corresponding to the steering angle signal θs as described above, but uses a constant gain Gx as the steering angular speed signal ωs. The second correction signal D2 may be calculated by multiplying by. In the case of such a configuration, the damping force Fd based on the second correction signal D2 depending on the steering angular speed ωs can be calculated, which is used for effectively suppressing the steering discomfort.

[Second Embodiment]
10 and 11 show a second embodiment of the electric power steering apparatus according to the present invention, which considers the reduction correction of the basic assist signal Ib for the control contents of the first embodiment. In each figure, the same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  FIG. 10 is a control block diagram relating to the steering assist torque correction control in the present embodiment.

  As shown in the drawing, the electronic control unit 8 according to the present embodiment performs limit processing on the steering torque signal Ts based on the steering torque signal Ts and the steering angle signal θs in addition to the configuration of the first embodiment. The torque limit processing unit 24 is provided, and the limit torque signal Ts ′ subjected to the limit processing in the torque limit processing unit 24 is input to the basic assist signal calculation unit 11 and the phase compensation calculation unit 12, and the limit torque signal Ts. The steering assist signal Ia is calculated based on the basic assist signal Ib ′ based on “and the phase compensation signal It ′”.

  Further, in the present embodiment, a correction gain calculation unit 25 that calculates a correction gain Ga that is a reduction correction signal of the steering assist signal Ia based on the steering angle signal θs is further provided. The motor command signal Io to the electric motor 7 is calculated by adding the correction control signal Dx to the reduction correction assist signal Ia ″ obtained by multiplying the steering assist signal Ia ′ by the corrected correction gain Ga. The correction gain calculation unit 25 and the integrator 26 constitute a basic assist command signal correction unit which will be described later.

  FIG. 11 is a flowchart relating to the steering assist torque correction control according to the present embodiment.

  As shown in the figure, first, the steering torque signal Ts detected by the torque sensor is read (step S201). Subsequently, the steering angle signal θs detected by the steering angle sensor is read (step S202), and the steering angular velocity signal ωs is calculated based on the read steering angle signal θs (step S203). And the code | symbol Sg of the steering angle signal (theta) s showing a steering direction is preserve | saved (step S204).

  Next, it is determined whether or not the absolute value | θs | of the steering angle signal θs read earlier is equal to or greater than the predetermined value Xs (step S205). The basic assist signal Ib and the phase compensation signal It are calculated based on the steering torque signal Ts (steps S206 and S207), and the damping processing signal Id is calculated based on the previously calculated steering angular velocity signal ωs (step S208). . Then, after calculating the steering assist signal Ia based on the calculated basic assist signal Ib, phase compensation signal It and damping processing signal Id (step S209), the steering torque signal previous value (the steering torque signal read in the previous job). ) Tx is updated with Ts (step S210), and the value obtained by adding the correction control signal Dx (calculated based on the flowchart shown in FIG. 3) to the steering assist signal Ia is output as the motor command signal Io (step S220). ), This program ends.

  On the other hand, when it is determined Yes in step S205, limit processing is performed on the previously read steering torque signal Ts with the previous value Tx so as not to exceed the previous value Tx (step S211). The basic assist signal Ib ′ and the phase compensation signal It ′ are calculated based on the steering torque signal (hereinafter abbreviated as “limit torque signal”) Ts ′ subjected to the limit processing (steps S212 and S213). After calculating the damping signal Id based on the previously calculated steering angular velocity signal ωs (step S214), the steering assist signal Ia ′ is calculated based on the signals Ib ′, It ′, Id (step S215). Subsequently, the correction gain Ga is calculated by referring to a predetermined map (not shown) based on the steering angle signal θs read in advance (step S216), and the calculated steering assist signal is calculated in advance. The reduction correction assist signal Ia ″ is calculated by integrating the value Ia ′ (step S217). Thereafter, the steering torque signal previous value Tx is updated with Ts (step S218), and the previously calculated reduction correction assist signal Ia ″ is obtained. The sum of the correction control signal Dx is output as a motor command signal Io (step S220), and this program ends.

  As described above, in this embodiment, in particular, in addition to the steering assist torque correction control calculated based on the first and second correction signals D1 and D2, the steering assist signal Ia itself that is the basis of the correction control is used. Therefore, the steering torque is sufficiently attenuated, and the collision with the rack stopper can be more effectively suppressed.

  Hereinafter, technical ideas other than those described in the scope of claims understood from the respective embodiments will be described.

(A) In the electric power steering apparatus according to claim 2,
The first correction amount calculation unit increases the steering angle signal when the steering angle signal is equal to or greater than the predetermined angle and the steering wheel is steered in a reversing direction opposite to the turning direction. The electric power steering apparatus characterized in that the first correction amount is calculated so as to increase with the change and to act in the switchback direction.

  According to such a configuration, it is possible to promote the rudder switchback by the spring reaction force in the switchback direction based on the first correction amount.

(B) In the electric power steering apparatus according to claim 1,
The first correction amount calculation unit and the second correction amount calculation unit are configured such that the sum of the first correction amount and the second correction amount is larger than the basic assist command signal. An electric power steering apparatus characterized by calculating a correction amount.

  By adopting such a configuration, it is possible to exert a sufficient damping action even when the steering operation is abrupt in the cutting direction.

(C) In the electric power steering apparatus according to claim 4,
The second correction amount calculation unit increases the steering angle signal when the steering angle signal is equal to or greater than the predetermined angle and the steering wheel is steered in a reversing direction opposite to the turning direction. The electric power steering apparatus characterized in that the second correction amount is calculated so as to increase along with the change back direction.

  According to this configuration, the steering operation in the rudder return direction can be smoothly performed by the damping force in the reverting direction based on the second correction amount.

(D) In the electric power steering apparatus according to claim 1,
The electric power steering apparatus, wherein the second correction amount calculation unit calculates the second correction amount by multiplying the steering angular velocity signal by a constant gain.

  With this configuration, it is possible to calculate the damping force based on the second correction amount that depends on the steering angular speed, and to effectively suppress the uncomfortable feeling of steering.

(E) In the electric power steering apparatus according to claim 1,
The control device corrects the basic assist command signal so that the basic assist command signal decreases when the steering angle signal is equal to or greater than the predetermined angle and the steering wheel is steered in the turning direction. An electric power steering apparatus, further comprising an assist command signal correction unit.

  According to such a configuration, in addition to the correction of the steering assist torque based on the first and second correction amounts, the basic assist command signal itself is also reduced and corrected, so that the steering torque is sufficiently attenuated. The collision with the rack stopper can be more effectively suppressed.

SW ... Steering wheel 2 ... Output shaft (pinion shaft)
2a ... pinion tooth 3 ... rack bar 3a ... rack tooth 7 ... electric motor 8 ... electronic control unit (control device)
Ts ... steering torque signal 10a ... steering torque signal receiving unit θs ... steering angle signal 10b ... steering angle signal receiving unit Ia ... steering assist signal (basic assist command signal)
15. Steering assist signal calculation unit (basic assist command signal calculation unit)
Io ... Motor command signal 16 ... Motor command signal output unit Xs ... Predetermined value (predetermined angle)
D1... First correction signal (first correction amount)
21 ... 1st correction signal calculating part (1st correction amount calculating part)
D2: Second correction signal (first correction amount)
22 ... 2nd correction signal calculating part (2nd correction amount calculating part)

Claims (2)

A steering mechanism having a pinion shaft that rotates in response to a steering operation of the steering wheel, and a rack bar that meshes with the pinion shaft and moves in the axial direction as the pinion shaft rotates to steer the steered wheels;
An electric motor for applying a steering assist torque to the steering mechanism;
A control device for driving and controlling the electric motor;
With
The controller is
A steering torque signal receiver for receiving a steering torque signal;
A steering angle signal receiving unit for receiving the steering angle signal;
A rudder angular velocity signal receiver for receiving a steering velocity signal;
A basic assist command signal calculation unit that calculates a basic assist command signal that is a basic command signal to the electric motor based on the steering torque signal;
When the steering angle signal is equal to or greater than a predetermined angle and the steering wheel is steered in the cutting direction, the steering angle signal increases with the increase in the steering angle signal and acts in a direction opposite to the cutting direction. A first correction amount calculation unit for calculating a correction amount;
When the steering angle signal is equal to or greater than a predetermined angle and the steering wheel is being steered in the cutting direction, the steering wheel speed signal increases with an increase in the steering angular velocity signal and acts in a direction opposite to the cutting direction. A second correction amount calculation unit for calculating the correction amount;
A motor command signal output unit that outputs a command signal to the electric motor based on the basic assist command signal, the first correction amount, and the second correction amount;
I have a,
The second correction amount calculation unit increases the steering angular velocity signal when the steering angle signal is equal to or greater than the predetermined angle and the steering wheel is steered in a reversing direction opposite to the turning direction. The electric power steering apparatus characterized in that the second correction amount is calculated so as to increase along with the cutting direction . A steering mechanism having a pinion shaft that rotates in response to a steering operation of the steering wheel, and a rack bar that meshes with the pinion shaft and moves in the axial direction as the pinion shaft rotates to steer the steered wheels;
An electric motor for applying a steering assist torque to the steering mechanism;
A control device for driving and controlling the electric motor;
With
The control device includes:
A steering torque signal receiver for receiving a steering torque signal;
A steering angle signal receiving unit for receiving the steering angle signal;
A rudder angular velocity signal receiver for receiving a steering velocity signal;
A basic assist command signal calculation unit that calculates a basic assist command signal that is a basic command signal to the electric motor based on the steering torque signal;
When the steering angle signal is equal to or greater than a predetermined angle and the steering wheel is steered in the cutting direction, the steering angle signal increases with the increase in the steering angle signal and acts in a direction opposite to the cutting direction. A first correction amount calculation unit for calculating a correction amount;
When the steering angle signal is equal to or greater than a predetermined angle and the steering wheel is being steered in the cutting direction, the steering wheel speed signal increases with an increase in the steering angular velocity signal and acts in a direction opposite to the cutting direction. A second correction amount calculation unit for calculating the correction amount;
A motor command signal output unit that outputs a command signal to the electric motor based on the basic assist command signal, the first correction amount, and the second correction amount;
Have
The electric power steering apparatus, wherein the second correction amount calculation unit calculates the second correction amount such that the second correction amount increases as the steering angle signal increases.

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