JP4715446B2 - Control device for electric power steering device - Google Patents

Description

  The present invention relates to a control device for an electric power steering device that applies a steering assist force by a motor to a steering system of an automobile or a vehicle, and in particular, a steering state (steering additional steering, steering switchback steering, or steering). Further, the present invention relates to a control device for an electric power steering device that compensates for self-aligning torque (SAT) based on steering angular velocity (motor speed), steering angle, and steering torque.

  An electric power steering device that assists an automobile or a vehicle steering device with an auxiliary load by the rotational force of a motor is a steering shaft or rack that transmits the driving force of the motor by a transmission mechanism such as a gear or a belt via a reduction gear. An auxiliary load is applied to the shaft. Such a conventional electric power steering apparatus performs feedback control of motor current in order to accurately generate assist torque (steering assist force). In the feedback control, the motor applied voltage is adjusted so that the difference between the current command value and the detected motor current is small. Generally, the adjustment of the motor applied voltage is a duty of PWM (pulse width modulation) control. This is done by adjusting the tee ratio.

  Here, the general configuration of the electric power steering apparatus will be described with reference to FIG. 6. The column shaft 2 of the steering handle 1 is connected to the steering wheel via the reduction gear 3, the universal joints 4 A and 4 B and the pinion rack mechanism 5. It is connected to the tie rod 6. The column shaft 2 is provided with a torque sensor 10 that detects the steering torque of the steering handle 1, and a motor 20 that assists the steering force of the steering handle 1 is connected to the column shaft 2 via the reduction gear 3. ing. The control unit 30 that controls the electric power steering apparatus is supplied with electric power from the battery 14 and is also supplied with an ignition key signal via the ignition key 11, and the control unit 30 detects the steering torque value detected by the torque sensor 10. A steering assist command value I of the assist command is calculated based on T and the vehicle speed V detected by the vehicle speed sensor 12, and a current supplied to the motor 20 is controlled based on the calculated steering assist command value I.

  The control unit 30 is mainly composed of a CPU (including an MPU). FIG. 7 shows general functions executed by programs in the CPU.

  The function and operation of the control unit 30 will be described with reference to FIG. 7. The steering torque value T detected and input by the torque sensor 10 and the vehicle speed V from the vehicle speed sensor 12 are a current command for calculating a current command value Iref. The value is input to the value calculation unit 31. Based on the input steering torque value T and vehicle speed V, the current command value calculation unit 31 determines a current command value Iref that is a control target value of the current supplied to the motor 20. The current command value Iref is input to the subtractor 32, and a deviation I (Iref-Im) from the fed back motor current value Im is calculated. The deviation I is supplied to the PI control unit 33 for improving the characteristics of the steering operation. Entered. The steering assist command value Vref whose characteristics have been improved by the PI control unit 33 is input to the PWM control unit 34, and the motor 20 is PWM driven via an inverter circuit 35 as a drive unit. The current value Im of the motor 20 is detected by the motor current detector 36 and fed back to the subtractor 32. The inverter circuit 35 uses an FET as a drive element, and is configured by an FET bridge circuit.

  Such an electric power steering apparatus has a self-aligning function. That is, in the process of returning to the straight traveling state after turning, if the driver loosens the force for rotating the steering wheel or sets it to zero (so-called hand release state), the wheel automatically tries to return to the neutral position direction. The self-aligning torque (SAT) for returning to the neutral position direction is larger as the vehicle speed is higher. At this time, in the electric power steering apparatus, first, if the wheel is steered to the right, for example, the wheel moves in the neutral position direction (left direction) by the self-aligning function. And since the force with which the driver rotates the steering wheel is zero, the steering torque should be zero. Therefore, the steering torque value detected by the torque sensor becomes zero, the motor is not energized, does not generate steering assist force, and rotates leftward while being connected to the electric steering device. Of course, the handle also rotates to the left.

  However, in the conventional electric power steering device, the steering wheel returns poorly at the time of low speed traveling due to frictional force corresponding to the motor rotor and the friction of the vehicle and the steering system, and the steering wheel feels at high speed traveling. There was a problem that the on-center feeling such as a feeling of friction and the like was bad.

  That is, in the process of returning to a straight-ahead state after turning the steering wheel by turning the steering wheel during low-speed traveling, the steering of the conventional electric power steering device is worse than the manual steering device or the hydraulic power steering device, and is serious. In some cases, the driver had to rotate the handle in the straight direction. Also, when driving at high speeds, the self-aligning function allows the wheels to be in a neutral position in the process of returning to the straight-ahead state after turning the steering wheel to change the lane or changing the direction (especially the process of returning in the hand-off state). When trying to return to the direction, the driver could not return to the middle (neutral position), and in a severe case, the driver had to rotate the handle in the straight direction.

  As a method for solving such a problem, a road surface reaction force torque detector is used as a handle return correction unit that corrects or cancels friction, and a handle angle detector that detects the rotation angle of the handle is used as the road surface reaction torque detector. A steering wheel return correction amount is obtained based on the steering wheel angle signal output from the steering wheel angle detector, and this correction amount can be adjusted to adjust the friction imbalance depending on the direction of rotation or movement of the steering wheel and the steering system. By doing so, a configuration has been proposed that eliminates the left-right difference in the handle return characteristics.

  Similarly, a road surface reaction force torque detector as a steering wheel return correction unit that corrects or cancels friction is constituted by road surface reaction force torque estimation means, and this road surface reaction force torque estimation means causes the motor torque output to be output to the steering torque detector. The steering shaft equivalent motor torque calculated from the output of the current detector for detecting the current is added, and the value obtained by subtracting the steering shaft equivalent motor inertia torque is subjected to low-pass filter or delay filter processing. A road surface reaction force torque estimation signal is generated, a steering wheel return correction amount is obtained based on the road surface reaction force torque estimation signal, and the friction imbalance due to the rotation or movement direction of the steering wheel and the steering system can be adjusted based on the correction amount. By doing so, it is also configured to eliminate the left-right difference in handle return characteristics There is also.

  The conventional example described above can be expected to improve the return of the steering wheel when the vehicle is released at low vehicle speeds. However, if the vehicle has a large friction, the steering force becomes too heavy when the steering wheel is increased. In general, the manual steering force when there is no power assist when turning the steering wheel while turning on a curve is a value obtained by adding the friction of the steering system to the reaction force from the road surface, which is heavier by the friction than the road surface reaction force, On the other hand, when returning the steering wheel, the value is obtained by subtracting the friction of the steering system from the road surface reaction force. For this reason, especially in vehicles with a large value of vehicle and steering system friction, there is a tendency for the amount of steering wheel return correction to overcome the friction and return the steering wheel. With the same coefficient based on the road surface reaction force, it becomes too heavy at the time of turning back the steering wheel at the time of turning at a low speed while requiring a good steering wheel return from a large rudder angle, resulting in a large imbalance. There was a drawback that caused.

As a solution to such a problem, for example, there is a control device for an electric steering device disclosed in Patent Document 1. The control device for this electric steering device is an electric power steering device that includes an electric motor that is inserted in a steering torque transmission mechanism from a handle to a wheel and generates a torque that assists a steering torque by a driver. A steering wheel return correction unit that corrects rotor friction and vehicle and steering system friction, and a steering state discrimination compensation unit that discriminates whether the steering wheel is turned up or down, and increases the correction amount of the steering wheel return correction unit. The value is set differently depending on the return direction.
JP 2002-294441 A

  However, the control device for the electric steering device disclosed in Patent Document 1 does not take into account self-aligning torque (SAT), but has only a problem of poor steering return when the steering wheel rotates at a low speed. Therefore, the road surface reaction force of the vehicle may be too strong, and the steering wheel may return too quickly.

  Further, in recent years, the size of vehicles equipped with electric power steering devices has been increasing, and in the control of conventional small vehicles, good steering feeling (especially during on-center and off-center, or steering during steering) There is a problem that (feeling) cannot be realized.

  The present invention has been made from the above circumstances, and an object of the present invention is to enable appropriate self-aligning torque compensation value (SAT compensation value) design at the time of on-center and off-center, An object of the present invention is to provide a control device for a high-performance electric power steering device that controls the SAT compensation value at the time of steering.

The present invention provides a current command value calculation unit that calculates a current command value based on a steering torque signal (T) from a steering torque detection means and a vehicle speed, and steers the steering mechanism based on the current value of the motor and the current command value. The above-mentioned object of the present invention relates to a control device for an electric power steering apparatus including a motor drive control unit that controls the motor for applying an auxiliary force, and the object of the present invention is to detect or estimate self-aligning torque (SAT). And a vehicle speed sensitive gain unit for setting a vehicle speed sensitive gain (G ₁ ) based on the vehicle speed, and a steering state is determined based on the steering torque signal (T) and the steering angular velocity signal (ω). results and the steering state determining section for outputting a determination signal according to the determination signal, the steering state feeling setting different steering state response gain (G ₂₎ A gain portion, the steering angular velocity signal on the basis of the (omega) and a omega sensitive gain unit for setting the omega sensitive gain (G 3 _(omega)), the self-aligning torque and (SAT) the vehicle speed sensitive gain (G ₁ ) multiplied by (SAT · G ₁ ) and further multiplied by the steering state sensitive gain (G ₂ ) (SAT · G ₁ · G ₂ ) is input to the first multiplier. And the ω-sensitive gain (G ₃ (ω)) is input to the first multiplication unit, and the multiplication result of the first multiplication unit is input to the second multiplication unit .

The above-described object of the present invention, further, the above based on the steering torque signal (T) to set the steering torque sensitive gain (G 4 _(T)) and a steering torque sensitive gain portion, the steering torque sensitive gain By using (G ₄ (T)) as the input of the second multiplication unit and the multiplication result of the second multiplication unit as the input of the third multiplication unit, or further, the steering angle signal (θ) setting a steering angle sensitive gain _(G 5 (θ)) on the basis of which a steering angle sensitive gain unit, and the steering angle sensitive gain _(G 5 (θ)) of the input of the third multiplier unit, the This is achieved more effectively by subtracting the self-aligning torque compensation value (SAT compensation value), which is the multiplication result of the third multiplication unit, from the current command value.

Further, the object of the present invention is to provide the steering state sensitive gain unit in which the steering state sensitive gain (G ₂ ) is negative when the determination signal represents steering switchback steering, and the determination signal increases the steering turn and performs steering. the steering state response gain to represent (G ₂₎ to 0, by the determination signal is to the steering state response gain (G ₂₎ to 0 to represent a fixed steering or by the steering state sensitive gain section The steering state sensitive gain (G ₂ ) is 0 when the determination signal represents steering return steering, and the steering state sensitive gain (G ₂ ) is positive when the determination signal represents steering increased steering. by determination signal and the steering state response gain (G ₂₎ to 0 to represent a fixed steering or, in the steering state sensitive gain section, the determination signal stearate Said to represent the return ring turn steering the steering state response gain (G ₂₎ 0, the steering state sensing gain when the determination signal represents a steering cutting center steering (G ₂₎ 0, the determination signal steering hold Is more effectively achieved by making the steering state sensitive gain (G ₂ ) positive, or by allowing the value of the steering state sensitive gain (G ₂ ) to be freely set.

  By using the control device for the electric power steering apparatus according to the present invention, the SAT compensation value is controlled on-center and off-center, and accordingly, an appropriate steering torque hysteresis width (SAT) at the time of on-center and off-center. Compensation value) design can be controlled, and steering torque hysteresis width at the time of steering is maintained by performing a steering state determination for determining a steering state (steering additional steering, steering switchback steering, or steering). It is also possible to control the design of (SAT compensation value).

  In the control device for the electric power steering apparatus according to the present invention, for example, when the steering angular speed is fast, such as letting go after the steering angle is input during traveling, the steering angular speed sensitive gain, the steering torque sensitive gain, and the steering angle sensitive Since the SAT compensation value is adjusted by using the gain at the same time, only the convergence can be improved without deteriorating the steering wheel return.

  By the way, when on-center (that is, when the steering torque is small or when the steering angle is small), by performing tuning that increases the SAT (steering torque), , There is a problem of feeling loss in response. In the control device for the electric power steering apparatus according to the present invention, when the steering angular velocity is high, the steering torque (responsiveness) is increased by using the steering angular velocity sensitive gain, that is, the viscosity feeling is increased. Since a compensation value is set, it is possible to prevent the occurrence of response loss.

  That is, according to the control device for an electric power steering apparatus according to the present invention, the steering angle is adjusted on the center at the time of traveling by using the steering angular velocity sensitive gain, the steering torque sensitive gain, and the steering angle sensitive gain. This produces an excellent effect of preventing the loss of steering response when shaken in small increments. In short, the present invention has the same effect as hydraulic power steering (check valve).

  The control device for an electric power steering apparatus according to the present invention is based on a steering state (steering additional steering, steering switchback steering, or steering), a steering angular velocity (motor speed), a steering angle, and a steering torque. Since the self-aligning torque (SAT) is compensated for, not only a small vehicle but also a large vehicle can realize a good steering feeling at the time of on-center and off-center as well as at the time of steering.

  In the present invention, by providing a steering angle sensitive gain and a steering torque sensitive gain (both or one), when the SAT is small (small steering torque / small steering angle) on-center and when the SAT is large (large steering torque / steering torque). It is possible to design appropriate SAT compensation values at off-center. In the present invention, it is possible to design a SAT compensation value at the time of steering by determining the steering state (steering additional steering, steering switching back steering, and steering).

  In short, in the present invention, using the determination result of the steering state (steering additional steering, steering switchback steering, and holding), the steering angular velocity signal, the steering torque signal, and the steering angle signal, the on-center state is turned off. The SAT compensation value at the center and at the time of steering is set appropriately.

  Preferred embodiments of the present invention will be described below in detail with reference to the drawings.

  FIG. 1 shows an embodiment of the present invention corresponding to FIG. 7. A steering torque value T from a torque sensor (not shown) is input to a current command value calculation unit 31 and a steering state determination unit 42. The vehicle speed V from the vehicle speed sensor (not shown) is input to the current command value calculation unit 31 and also to the vehicle speed sensitive gain unit 41. The current command value Iref calculated by the current command value calculation unit 31 based on the steering torque value T and the vehicle speed V is input to the subtractor 65.

The self-aligning torque SAT detected or estimated by the self-aligning torque unit 40 is input to the multiplication unit 60. A vehicle speed sensitive gain unit 41, a vehicle speed sensitive gain G ₁ based on the vehicle speed V is set. The vehicle speed sensitive gain G ₁ from the vehicle speed sensitive gain unit 41 is also input to the multiplying unit 60. The output SAT · G ₁ of the multiplier 60 is input to the multiplier 61.

On the other hand, the steering state determination unit 42 receives the measured or estimated steering angular speed ω (motor speed). In the steering state determination unit 42, based on the steering torque value T and the steering angular velocity ω,
The steering state (steering additional steering, steering switchback steering, or steering control) is determined, and a determination signal (that is, a signal indicating the determined steering state) is output to the steering state sensitive gain unit 43 as a result of the determination. To do.

The steering state sensitive gain unit 43 switches the steering state sensitive gain G < _b > ₂ based on the determination signal from the steering state determination unit 42. That is, the steering state sensitive gain G ₂ output from the steering state sensitive gain unit 43 to the multiplying unit 61 is switched according to the determination signal from the steering state determining unit 42.

Figure 2 shows a specific example of the steering state sensitive gain G _2. In the steering state sensitive gain unit 43, as shown in FIG.
The steering state sensitive gain G ₂ when it is determined that the steering switchback steering negative (e.g., the value of G ₂ to -1 and -0.5), steering state sensitive when it is determined that the steering cutting center steering gain G ₂ 0, "the functioning of the steering switchback steering only when the steering state sensitive gain G _2" steering state sensitive gain G ₂ 0 to a case where it is determined that the steering holding pattern (a),
The steering state sensitive gain G ₂ when it is determined that the steering switchback steering 0, the steering state sensitive gain G ₂ positive (e.g., the value of G ₂ to 1 or 2 when it is determined that the steering cutting center steering ) “Steering state sensitive gain G _{2 is made} to function only when steering is increased and steering is performed”, in which the steering state sensitive gain G ₂ is determined to be 0 when the steering is determined to be maintained (B),
Steering state sensitive gain G ₂ 0 when it is determined that the return steering turn steering, the steering state sensitive gain G ₂ when it is determined that the steering-cutting center steering 0, the steering state response gain when it is determined that steering hold A combination of several patterns such as a pattern (C) in which G ₂ is positive (for example, the value of G ₂ is set to 1 or 5) and “the steering state sensitive gain G ₂ is allowed to function only at the time of steering” is possible. and the value of the steering state sensitive gain G ₂ is also freely settable.

The outputs SAT · G ₁ · G ₂ of the multiplier 61 are input to the multiplier 62. The ω-sensitive gain G ₃ (ω) set by the ω-sensitive gain unit 44 is also input to the multiplying unit 62. The output SAT · G ₁ · G ₂ · G ₃ (ω) of the multiplier 62 is input to the multiplier 63. The steering torque sensitive gain G ₄ (T) set by the steering torque sensitive gain unit 45 is also input to the multiplier 63. The output SAT · G ₁ · G ₂ · G ₃ (ω) · G ₄ (T) of the multiplier 63 is input to the multiplier 64. The steering angle sensitive gain G ₅ (θ) set by the steering angle sensitive gain unit 46 is also input to the multiplication unit 64. The output SAT · G ₁ · G ₂ · G ₃ (ω) · G ₄ (T) · G ₅ (θ) of the multiplier 64, that is, the SAT compensation value referred to in the present invention is input to the subtractor 65. The subtraction result (Iref-SAT compensation value) in the subtractor 65, that is, (Iref-SAT · G ₁ · G ₂ · G ₃ (ω) · G ₄ (T) · G ₅ (θ)) is a current command. The value Iref1 is input to the adder 66, and the compensation signal CM from the compensation unit 50 for improving characteristics is also input to the adder 66.

  The compensation unit 50 adds the inertia 51 and the convergence 52 with the adder 53 and inputs the addition result to the adder 66 as the compensation signal CM. The addition result (Iref1 + CM) in the adder 66 is input to the subtractor 67 as a current command value Iref2, and the motor 20 is controlled through the PI control unit 33, the PWM control unit 34, and the inverter 35.

  As shown in the flowchart of FIG. 3, the steering state determination unit 42 first determines whether or not the steering angular velocity ω remains the same value (or a range of values) for a certain period of time (step S31), and determines that it has continued. If it is, it is determined that the steering is maintained (step S32). On the other hand, when it is determined that the steering is not continued, it is determined that the steering is performed (step S33), and it is further determined whether or not the sign of the steering torque value T matches the sign of the steering angular velocity ω (step S34). When it is determined that the sign of the steering torque value T and the sign of the steering angular velocity ω coincide with each other, it is determined that the steering is further turned up (step S35). On the other hand, when it is determined that the sign of the steering torque value T and the sign of the steering angular velocity ω do not match, it is determined that the steering is turned back (step S36).

  In short, the steering state determination unit 42 outputs a ternary (steering additional steering, steering switchback steering, and steering hold) determination signal to the steering state gain unit 43 in accordance with the operation shown in the flowchart of FIG.

  Further, if the steering state determination unit 42 does not determine the steering hold and determines only the steering turning increase steering and the steering switching back steering, the sign of the steering torque value T is disclosed in JP-A-2003-170856. And the sign of the steering torque change rate are the same, and the absolute value of the steering torque change rate is equal to or greater than a predetermined value, it is determined that the steering is increased and the sign of the steering torque value T and the sign of the steering torque change rate are determined. May be determined to be steering switchback steering when the signs are different from each other and the absolute value of the steering torque change rate is equal to or greater than a predetermined value. That is, the steering state determination unit 42 can determine the steering turning increase steering and the steering switching back steering by using only the steering torque value T without using the steering angular velocity ω.

  In the self-aligning torque unit 40, the self-aligning torque SAT may be estimated by a disturbance observer configuration using a motor rotation signal and a motor current command value as disclosed in, for example, JP-A-2002-274405. .

The ω-sensitive gain unit 44 sets the ω-sensitive gain G ₃ (ω) based on the steering angular velocity signal ω. As a specific example of the ω-sensitive gain G ₃ (ω), for example, FIG. A first-order lag function G ₃ (ω) of the steering angular velocity signal ω as shown in (A) can be used.

The steering torque sensitive gain unit 45 sets a steering torque sensitive gain G ₄ (T) based on the steering torque signal T. As a specific example of the steering torque sensitive gain G ₄ (T), for example, A first-order lag function G ₄ (T) of the steering torque signal T as shown in FIG. 4B can be used.

Further, the steering angle sensitive gain unit 46 sets the steering angle sensitive gain G ₅ (θ) based on the steering angle signal θ. As a specific example of the steering angle sensitive gain G ₅ (θ), for example, A first-order lag function G ₅ (θ) of the steering angle signal θ as shown in FIG. 4C can be used.

In place of the first-order lag functions G ₃ (ω), G ₄ (T), and G ₅ (θ) used in the ω-sensitive gain unit 44, the steering torque-sensitive gain unit 45, and the steering angle-sensitive gain unit 46, A linear function may be used.

FIG. 5 is a flowchart showing the operation of the control device for the electric power steering apparatus according to the present invention. That is, as shown in FIG. 5, in the present invention, first, the self-aligning torque SAT is estimated by the self-aligning torque unit 40 (step S1). Then, the vehicle speed sensitive gain G ₁ based on the vehicle speed V by the vehicle speed sensitive gain unit 41 is calculated (step S2). In addition, the steering state determination unit 42 determines the steering state (steering additional steering, steering switchback steering, and steering), and a determination signal is output (step S3).

Next, whether the steering state sensitive gain G ₂ is calculated in accordance with the determination signal by the steering state sensitive gain unit 43 (step S4). Further, the ω-sensitive gain unit 44 calculates the ω-sensitive gain G ₃ (ω) based on the steering angular velocity signal ω (step S5). The steering torque sensitive gain unit 45 calculates the steering torque sensitive gain G ₄ (T) based on the steering torque signal T (step S6). The steering angle sensitive gain unit 46 calculates a steering angle sensitive gain G ₅ (θ) based on the steering angle signal θ (step S7).

Thus, “self-aligning torque SAT”, “vehicle speed sensitive gain G ₁ ”, “steering state sensitive gain G ₂ ”, “ω sensitive gain G ₃ (ω)”, “steering torque sensitive gain G ₄ (T)”. , “Steering angle sensitive gain G ₅ (θ)” is calculated, so “SAT compensation value” can be calculated. That is, “SAT compensation value” = “SAT · G ₁ · G ₂ · G ₃ (ω) · G ₄ (T) · G ₅ (θ)” is established (step S8).

It is a block block diagram which shows the Example of this invention. It is a figure which shows the specific example of the steering state sensitive gain set in the steering state sensitive gain part in this invention. It is a flowchart for demonstrating the operation example of the steering state determination part in this invention. It is a figure which shows the specific example of each gain set in the (omega) sensitive gain part in this invention, a steering torque sensitive gain part, and a steering angle sensitive gain part. It is a flowchart for demonstrating the operation example of the control apparatus of the electric power steering apparatus which concerns on this invention. It is a figure showing an example of composition of a general electric power steering device. It is a block block diagram which shows an example of a control unit.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Steering handle 2 Column shaft 3 Reduction gear 4A, 4B Universal joint 5 Pinion rack mechanism 6 Tie rod 10 Torque sensor 11 Ignition key 12 Vehicle speed sensor 14 Battery 20 Motor 30 Control unit 31 Current command value calculation part 33 PI control part 34 PWM control Unit 35 inverter circuit 36 motor current detector 40 self-aligning torque unit 41 vehicle speed sensitive gain unit 42 steering state determining unit 43 steering state sensitive gain unit 44 ω sensitive gain unit 45 steering torque sensitive gain unit 46 steering angle sensitive gain unit 50 compensation Unit 51 Inertia 52 Convergence 60, 61, 62, 63, 64 Multiplier 65, 67, 32 Subtractor 66, 53 Adder

Claims (7)

A current command value calculation unit for calculating a current command value based on the steering torque signal (T) from the steering torque detection means and the vehicle speed, and a steering assist force to the steering mechanism based on the current value of the motor and the current command value In the control device of the electric power steering device comprising a motor drive control unit for controlling the motor
A self-aligning torque unit for detecting or estimating self-aligning torque (SAT);
A vehicle speed sensitive gain unit that sets a vehicle speed sensitive gain (G ₁ ) based on the vehicle speed;
A steering state determination unit that determines a steering state based on the steering torque signal (T) and the steering angular velocity signal (ω), and outputs the determined result as a determination signal;
A steering state sensitive gain unit for setting a different steering state sensitive gain (G ₂ ) according to the determination signal ;
A ω-sensitive gain unit that sets a ω-sensitive gain (G ₃ (ω)) based on the steering angular velocity signal (ω) ,
A value obtained by multiplying the self-aligning torque (SAT) and the vehicle speed sensitive gain (G ₁ ) (SAT · G ₁ ) by the steering state sensitive gain (G ₂ ) (SAT) (G ₁ · G ₂ ) as the input of the first multiplier ,
The electric power steering apparatus characterized in that the ω-sensitive gain (G ₃ (ω)) is used as an input to the first multiplication unit, and a multiplication result of the first multiplication unit is used as an input to a second multiplication unit. Control device. A steering torque sensitive gain unit for setting a steering torque sensitive gain (G ₄ (T)) based on the steering torque signal (T);
2. The electric power according to claim 1 , wherein the steering torque sensitive gain (G ₄ (T)) is an input of the second multiplication unit, and a multiplication result of the second multiplication unit is an input of a third multiplication unit. Steering device. And a steering angle sensitive gain unit for setting a steering angle sensitive gain (G ₅ (θ)) based on the steering angle signal (θ).
The steering angle sensitive gain (G ₅ (θ)) is used as an input to the third multiplication unit, and a self-aligning torque compensation value (SAT compensation value) that is a multiplication result of the third multiplication unit is used as the current command value. The electric power steering apparatus according to claim 2 , wherein the electric power steering apparatus is subtracted from the electric power steering apparatus. In the steering state sensitive gain unit, the steering state sensitive gain (G ₂ ) is negative when the determination signal represents steering return steering, and the steering state sensitive gain ( the G ₂₎ 0, the determination signal controller of an electric power steering apparatus according to claim 3, wherein the steering state response gain (G ₂₎ to 0 to represent a fixed steering. In the steering state sensitive gain unit, the steering state sensitive gain (G ₂ ) is set to 0 when the determination signal represents steering return steering, and the steering state sensitive gain ( The control device for an electric power steering apparatus according to claim 3 , wherein G ₂ ) is positive, and the steering state sensitive gain (G ₂ ) is set to 0 when the determination signal indicates steering retention. In the steering state sensitive gain unit, the steering state sensitive gain (G ₂ ) is set to 0 when the determination signal represents steering return steering, and the steering state sensitive gain ( The control device for an electric power steering apparatus according to claim 3 , wherein G ₂ ) is 0, and the steering state sensitive gain (G ₂ ) is positive when the determination signal indicates steering retention. Control device for an electric power steering apparatus according to any one of claims 4 to 6 and freely set the value of the steering state response gain (G _2).

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