JP2002274404A - Electric power steering device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize an electric power steering device free from the vibration of a steering wheel even in the case when a comparatively inexpensive steering angle sensor of comparatively long detection period is used. SOLUTION: A torque command generating part (target value generating means) is provided with a reaction force command value operating part (base item generating means) and a damper item generating means arranged in parallel. In detail, as a concrete embodiment is exampled in 'more detailed control block diagram of target value generating means' of Fig. 3, the torque command generating part (target value generating means) is provided with a LPF processing part 402 (detected angular speed vibration reducing means), a steering angle estimation processing part 403 (steering angle estimating means), a target value correction processing part 408 (command value vibration reducing means) and the like, which is largely different from a conventional device. According to the present electric power steering device 100, the vibration of the steering wheel can be effectively inhibited by the vibration reducing action on the basis of the estimation processing and the correction processing relating to the detection values and the command values.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle-mounted electric power steering device for assisting a driver of a vehicle.

[0002]

2. Description of the Related Art A steering torque applied to a steering wheel by a driver based on a desired steering feeling model and a real-time detection value such as a steering angle θ (ie, a rotation angle of a steering wheel) and a vehicle speed V. An “electric power steering device” that calculates a target value h to be reached by q and controls the auxiliary torque output motor so that the steering torque q follows the target value h has been devised.

FIG. 8 is a control block diagram illustrating an outline of a general control method of an electric power steering apparatus using a steering torque control means (62) set so as to secure robust stability. The steering angle θ of the steering wheel output from the steering angle sensor 16 is differentiated by the steering angle differentiator 64 and input to the target value generator 61. The steering angle θ is also input to the target value generation means 61.
The target value generating means 61 outputs a target value h of the steering torque based on the vehicle speed V, the steering angle θ, or the angular speed ω (= dθ / dt), for example, according to a desired steering feeling model.
Generate

[0004] The steering torque control means 62 is based on a deviation (h-q) between the target value h output from the target value generation means 61 and the steering torque q detected by the torque sensor 12.
In order to reduce this deviation, the current command value setting means 63
It calculates a current command value I _A by. That is, the current command value I _A is calculated as the steering torque q follows the target value h. The current command value calculating means 63 is a compensator (robust controller) composed of, for example, a PID controller or the like, and stabilizes a feedback loop of the steering torque q (so that robust stability is ensured). ) Is set. Therefore, as the current command value calculating means 63, for example, one having a transfer function set by H∞ control theory may be used.

FIG. 9 is a control block diagram illustrating a control method (example 1) of the target value generating means 61 (FIG. 8) which is currently being devised. For example, in the control block diagram (FIG. 9), firstly, the steering angle theta, the vehicle speed V, depending on the angular velocity omega, determines a target value h _1, then the gain G depending from the map M2 to the vehicle speed V at that time Determine ₁

Thereafter, a target value h ₂ for the angular velocity ω is determined from the map M3, and then a gain G ₂ is determined from the map M4 according to the vehicle speed V. Further, these two target values h ₂ are determined.
_1, with h ₂ and the gain G _1, G _2, and finally for example, the following equation (1), to obtain the target value h by calculation format as shown in (2).

H = E (V, θ, ω) (1)

E (V, θ, ω) = G ₁ · h ₁ + G ₂ · h ₂ (2)

For example, the vehicle speed, steering angle,
The target value h can be determined so that a steering feeling can be obtained according to the steering angular velocity, and the detected steering torque q follows the target value h determined in this manner. The steering torque control means 62 described above can be operated. That is, by the control method as described above, it is possible to realize a predetermined steering feeling model while securing robust stability.

Further, conventional target value generating means (61 in FIG. 8)
FIG. 10 exemplifies a control block diagram of another control method (corresponding to FIG. 2) (Example 2). This control method (Example 2)
Here, the function E of the above (1) is defined in the form of the following equations (3) to (5).

E (V, θ, ω) = τ + T _D (3)

Τ = E1 (V, θ) (4)

T _D = E 2 (ω) (5) Here, the function E 1 is a multi-valued function related to the steering angle θ and has a hysteresis characteristic. The “turn-up / turn-back determination means” in the figure is a means for uniquely determining a reaction force command value based on a multivalent function having a hysteresis characteristic. Further, the function E2 may be, for example, a linear equation or the like, and can be realized by relatively simple arithmetic processing such as multiplying a predetermined damper gain by the angular velocity ω.

By separating the argument ω (independent variable) from the other arguments (independent variables V, θ) using such an arithmetic format, the design, manufacture, adjustment, and the like of the hysteresis characteristic (function E1) are significantly improved. Therefore, it is possible or much easier to realize a desired steering feeling that is more suitable for the sense of the driver assumed.

[0010] Also, using such an arithmetic form, the argument ω
By separating the (independent variable) from the other arguments (independent variables V, θ), the “function extremely sensitive to the displacement of the angular velocity ω near the origin” such as the hysteresis map M3 in FIG. In some cases, the vibration of the steering wheel can be suppressed.

[0011]

However, when a steering angle sensor having a relatively long detection cycle of the steering angle θ of the steering wheel (steering wheel) (hereinafter sometimes referred to as “steering wheel angle”) is used. Since the change amount (displacement) of the steering angle θ per one detection cycle of the steering angle θ is likely to be large, a vibration component appears in the torque command value, and as a result, the steering wheel may vibrate.

FIG. 11 shows a conventional target value generating means (FIG. 10).
7 is a graph illustrating the behavior of the steering wheel of the electric power steering device using the control method (Example 2). This figure 1
As can be seen from FIG. 1 (b), when the detection cycle of the steering wheel angle is relatively long, for example, about 20 to 40 ms, the steering wheel angle (steering angle θ) changes stepwise with time. A vibration component also appears in the torque command value (or the current command value), and as a result, the handle may vibrate.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problem, and an object of the present invention is to provide a steering wheel which can be used even when a relatively inexpensive steering angle sensor having a relatively long steering angle detection cycle is used. An object of the present invention is to realize an electric power steering device in which vibration is less likely to occur.

[0014]

Means for Solving the Problems, Functions and Effects of the Invention In order to solve the above-mentioned problems, the following means are effective. That is, the first means includes a motor for providing an assist torque to the steering mechanism for assisting the steering of the vehicle, a torque sensor for detecting a steering torque q applied to the steering wheel by the driver, and a running speed (vehicle speed V) of the vehicle. Speed sensor for detecting vehicle speed and steering wheel rotation angle (steering angle θ)
In the electric power steering device having a steering angle sensor for detecting the steering angle and a motor control device for controlling the driving of the motor, a steering angle extrapolation process based on the detected value of the steering angle θ is used to estimate the current or near current steering angle θ. Steering angle estimating means for calculating the value Θ substantially periodically at a cycle shorter than the output cycle of the steering angle sensor, and target value generating means for calculating a target value h to be reached by the steering torque q based on at least the estimated value Θ When, is that steering torque q is provided a steering torque control means for determining a command value I _a of the drive current of the motor so as to follow the target value h.

By introducing the steering angle estimating means of the present invention for executing the steering angle extrapolation processing as described above, the steering wheel angle is calculated relatively accurately in a cycle shorter than the detection cycle of the steering wheel angle (steering angle θ) ( Estimation). For this reason, according to the first means, even when a relatively inexpensive steering angle sensor having a relatively long detection cycle of the steering wheel angle is used, the vibration of the steering wheel can be suppressed. Therefore, according to the present invention, it is possible to configure an electric power steering device in which the steering wheel does not easily vibrate relatively inexpensively.

[0016] The second means is the target value generating means of the first means, and further comprises the step of setting a target value h based on at least one of the rotational angular velocity ω of the steering wheel and the vehicle speed V. It is to calculate. By using such a means, for example, even under the configuration of the target value generating means and the like illustrated in FIG. 10 described above, the above-described first means can be applied. The device can be configured.

Further, the third means may be the first or the second means.
Means for removing a vibration component in a specific frequency band of the rotational angular velocity of the steering wheel calculated based on the detected value of the steering angle θ.
And the steering angle estimating means calculates the estimated value Θ based on the rotational angular velocity ω calculated by the detected angular velocity vibration reducing means.

The use of such a detected angular velocity vibration mitigation means makes it possible to make the fluctuation of the rotational angular velocity ω, which tends to be unstable by a differential operation, relatively stable, and as a result, the rotational angular velocity It is possible to intensively suppress a vibration component having a frequency that easily gives a human body a discomfort of ω. Also, noise that easily appears in the numerical value of the rotational angular velocity ω can be reduced.

Therefore, if the steering angle estimating means calculates the estimated value 舵 of the steering angle based on the rotational angular velocity ω calculated by the detected angular velocity vibration mitigation means, the estimation accuracy of the steering angle is improved, and The vibration suppression effect on the value Θ is obtained. That is, by these actions, the vibration of the torque command value and the vibration of the steering wheel itself can be suppressed more reliably.

Further, the fourth means includes the first to third means.
In any one means, said target value h, the command value I _A or output value h by shortening using a predetermined interpolation / extrapolation output cycle of these related values x, I _A or x In order to reduce the fluctuation amount per one output cycle, "command value vibration reducing means" is provided.

According to this means, a control command (torque command) can be constituted or made easier with a finer cycle. For this reason, the vibration of the handle can be suppressed more reliably or easily. Further, according to this means, independently of the specifications such as the steering angle detection cycle of the steering angle sensor, independently of the specifications such as the steering torque detection cycle or the control cycle of the system constituting the robust torque loop, independently. Target value h
Can be determined. Therefore, the independence between the robust torque loop component and the target value generating means is greatly improved, and the design time and adjustment time for each part can be reduced, thereby improving the productivity.

The fifth means includes the first to fourth means.
And a damper dependent on at least the rotational angular velocity ω of the steering wheel, wherein the target value generating means generates a basic term dependent on at least the estimated value Θ based on a predetermined hysteresis characteristic. And damper term generating means for generating terms are provided independently of each other or in parallel.

According to this means, for example, the above equation (3)
A simple configuration represented by the above-described control method (Example 2) based on (5) to (5) can be adopted, so that the structure of the system can be simplified and the functions E1, E
The independence or parallelism of 2 makes it easy to design, manufacture, and adjust the target value generation means. Further, by using this means, the vibration of the handle can be suppressed in substantially the same manner as the above-described operation principle. According to this means, it is possible or easy to improve "convergence" typified by the convergence characteristic of the steering wheel to the equilibrium point when the driver releases his / her hand from the steering wheel.

Further, the sixth means includes the first to fifth means.
In the target value generation means or the steering torque control means of any one of the means, a transfer function set to ensure robust stability against a model error and a disturbance of a control model of the electric power steering device is used. , Target value h,
It is to determine the command value I _A, or a related value x.

According to such means, since the target value does not affect the stability of the feedback loop of the steering torque, there is no need to readjust the steering torque control means in the feedback loop of the steering torque, and the steering feeling is adjusted. Can be done efficiently. Since the target value can be set to any size, the steering wheel can be set to any weight. Further, by generating the target value based on the speed of the vehicle, the rotation angle of the steering wheel, and the rotation angular speed of the steering wheel, it is possible to give an optimum steering feeling to a traveling state or a steering state.

Further, the steering torque control means generates a current command value using a transfer function set to ensure robust stability against a model error of the control model of the electric power steering apparatus and a disturbance. By doing so, the stability is increased and the vibration of the steering handle is suppressed to a smaller level, so that a more optimal steering feeling can be given. As for the characteristic of the target value with respect to the vehicle speed v, the target value may be reduced as the vehicle speed v increases. As a result, the steering feeling can be reduced as the vehicle speed increases.

As for the characteristic of the target value with respect to the steering angle θ, the target value may be increased as the steering angle θ increases. By setting in this manner, the characteristic is obtained that the steer the steering wheel is turned, the heavier the steering feeling becomes. Further, the target value may be increased as the steering angular velocity ω (= dθ / dt) increases. With this setting, for the same reasons as above,
As the steering angular velocity increases, the steering feeling of the steering wheel can be increased.

The target torque characteristic may be set by an arbitrary combination of these. As described above, by setting the target value according to the traveling state and the steering state, it is possible to obtain an optimal steering feeling in the state at that time.

The target value may be changed by an arbitrary function according to a combination of two or three of the vehicle speed, the steering angle, and the steering angular speed. Further, the target value may be changed in consideration of the steering frequency and the like. That is, when the steering frequency is high,
Continuous curve running is conceivable. In this case, running stability can be maintained by setting the steering handle to a heavy steering feeling. The above means can effectively solve the above-mentioned problem.

[0030]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described based on specific embodiments. However, the present invention is not limited to the embodiments described below. FIG. 1 is a logical hardware configuration diagram of an electric power steering apparatus 100 according to a specific embodiment of the present invention.

The steering wheel 10 is fixed to a steering shaft 11, and a torque sensor 12 is provided on the steering shaft 11. The manual torque applied to the steering shaft 11 is transmitted to the rack 14 via the pinion gear 13, and the steering wheels 41, 4
Used to change direction 2. As is well known, the torque sensor 12 detects a torque generated when the steering wheel 10 is operated and the steering shaft 11 is twisted. That is, when steering at a constant speed, the torque obtained by subtracting the assist torque by the electric motor from the reaction torque received by the steered wheels 41 and 42 from the road surface becomes equal to the manual torque applied for steering by the driver. This torque is detected as the torsional torque of the steering shaft 11.

The output signal from the torque sensor 12 is A
The signals are sampled at very short time intervals by the / D converter 18, converted into digital signals, and input to the CPU 20. The vehicle speed v output from the vehicle speed sensor 15 and the steering angle θ output from the steering angle sensor 16 are input to the CPU 20. The CPU 20 includes a ROM 21 storing programs and maps, and a RAM 22 storing various data.
Is connected. The output signal from the CPU 20 is input to the driver circuit 25, and the driver circuit 25 (motor driving means) drives the motor 31 having a built-in reduction gear. As the electric motor 31 rotates, assist torque is applied to the steered wheels 41 and 42 via the pinion gear 32 and the rack 14. Target value generation means 6
1 and the steering torque control means 62
It is configured by a computer system including a ROM 21, a RAM 22, and the like.

Incidentally, the above-mentioned configuration is the same as that of the above-mentioned 10 to 14, 3
A mechanical system (power steering system) having a control target including 1, 32, 41, 42, a speed reducer, and the like;
It is roughly divided into a controller system that includes 20, 21, 22, 25, a power supply circuit (not shown), and the like to realize electronic control.

FIG. 2 is a control block diagram showing a logical outline of a control system of the electric power steering apparatus 100 described above. The “torque command generation unit” in FIG. 2 constitutes a part corresponding to the target value generation means 61 in FIG. 8, and a compensator (robust controller) 6
3 corresponds to the current command value calculating means 63 in FIG.
That is, the torque command generator (target value generator) of the present embodiment.
Has a reaction force command value calculation unit (basic term generation means) and a damper term generation means in parallel, as can be seen from FIG. 2 (or FIG. 3), and the above equations (3) to (5) And a target value h of the steering torque is calculated in a manner substantially similar to the above-described control method (Example 2) in a manner substantially conforming to Expression (1).

However, in more detail, the "more detailed control block diagram of the target value generating means" in FIG.
As illustrated in the example, in the torque command generation unit (target value generation unit) of the present embodiment, the LPF processing unit 402 (detection angular velocity vibration reduction unit) and the steering angle estimation processing unit 403 (steering angle estimation unit)
In addition, the point that a target value correction processing unit 408 (command value vibration mitigation means) and the like are provided is a big feature different from the conventional one.
With these functions, according to the electric power steering apparatus 100 of the present embodiment, the vibration of the steering wheel can be effectively suppressed.

Hereinafter, the torque command generator (target value generator) of FIG. 3 will be described in accordance with the flowchart of the "target value calculation processing program" for realizing the target value generator of the present embodiment of FIGS. Will be described.

In the target value calculation processing program, first, at step 510, the current time t is stored in a time variable t1, which is a predetermined time save area. Next, in step 520, the steering angle θ and the vehicle speed V are input from the steering angle sensor 16 and the vehicle speed sensor 15, respectively. Next, step 53
In the case of 0, the angular velocity ω of the steering wheel (steering wheel 10) is calculated as a provisional value based on the amount of displacement of the steering angle θ from one input cycle before.

Next, at step 540, the LPF processing section 402 (detection angular velocity vibration mitigation means) determines the steering wheel angular velocity ω properly. In the LPF (low-pass filter) process, a known or appropriate LPF process is used to remove a vibration component in a specific frequency band of the rotational angular velocity of the steering wheel tentatively calculated based on the detected steering angle θ. Thus, the angular velocity ω of the steering wheel is determined.

Next, at step 550, the current time t is stored in a time variable t2 which is a predetermined time save area. In step 560, the elapsed time Δt from the previous input time t1 of the steering angle θ to the present is calculated. In step 570, the steering angle estimation processing unit 403 (steering angle estimation means) calculates an accurate value (estimated value) 現在 of the current steering angle according to the following equation (6) based on the input value or the calculation result. I do.

６ = θ + ωΔt (6) where the variables θ, ω, and Δt have the values obtained in the above-described steps 520, 540, and 560, respectively.

The extrapolation processing of the equation (6) includes:
Other known extrapolation methods may be used. That is, more generally, as these extrapolation processes, for example, an appropriate arbitrary method such as using an n-order approximation (n ≧ 1) or approximating using an m-order function (m ≧ 1) is used. It is possible to take measures. For example, these values of n and m may be determined in consideration of various trade-off factors such as program development costs, CPU calculation capability, and required steering angle calculation accuracy. Of course, the same applies to the case where other general extrapolation methods are introduced.

At step 580, the turning direction of the steering wheel is determined by the additional turning / returning determining unit 404 (rotation direction determining means). However, this determination process may be executed by determining the sign of the angular velocity ω used in the above equation (6).

Steps 610 to 630
In (FIG. 5), the reaction force command value calculation unit 405 (basic term generation means) of FIG. 3 is executed. That is, first, in step 610, an interpolation process of the vehicle speed V is performed. Thus, a more accurate value (correction value or estimated value) can be used for the vehicle speed V. Next, at step 620, a “hysteresis curve used for calculating a reaction force command value” as exemplified in FIG. 6 is determined based on the vehicle speed V. In the present embodiment, for example, the target value of the reaction force of the steering wheel associated with the steering, that is, the reaction force command value τ is calculated, for example, as described in the above equation (4). Since the hysteresis curve can be determined (tuned) independently of the value, such a hysteresis curve can be designed (tuned) more easily than in the past.

In step 630, a reaction force command value τ is determined based on the determination result in step 580, the hysteresis curve, and the estimated steering angle Θ obtained in step 403. In step 640, the damper gain multiplication unit 406 (damper section generating means), to determine the value of damper torque T _D on the basis of the angular velocity omega. The value of the damper torque T _D can be determined for example according to the formula (5) or the like, for example, an angular velocity ω
May be a value that is substantially proportional to.

In step 650, the target value h is determined by the torque command value adder 407 according to the above equation (3). In step 660, the target value correction processing unit 408 (command value vibration mitigation means) executes a correction process of the target value h based on a predetermined interpolation process or a predetermined extrapolation process, and the robust torque loop shown in FIG. Output to

In step 670, the process waits until the next output cycle of the target value h to the robust torque loop of FIG. 2 comes. This output cycle is shorter than the above-described determination cycle (calculation cycle) of the reaction force command value τ. In step 680, it is determined whether or not the determination cycle (calculation cycle) of the reaction force command value τ has come,
If the calculation time has been reached, the process proceeds to step 690; otherwise, the process proceeds to step 660.

In step 690, it is determined whether or not the input cycle of the steering angle θ has arrived. If the input time has been reached, the process proceeds to step 510; otherwise, the process proceeds to step 550. Here, ΔT is a constant representing the input cycle of the steering angle θ. For example, the above-described “target value calculation processing program” can be realized by the above processing flow.

FIG. 7 is a graph illustrating a measured record of the behavior of the steering wheel (steering wheel 10) of the electric power steering apparatus 100 according to the present embodiment. This measurement record was recorded under substantially the same measurement conditions as the measurement record of the prior art shown in FIG. From FIG. 7, it can be seen that according to the present invention, the vibration of the steering wheel can be suppressed much more effectively than in the prior art.

As a method of calculating the damper torque T _D , it is not always necessary to use the above-described formula (5). That is, as a calculation method of the damper torque T _D ,
A well-known calculation method conventionally used or any appropriate calculation method can be used.

FIG. 12 is a control block diagram illustrating another control method in another conventional electric power steering apparatus. For example, as seen in this conventional example, also in the embodiments of the invention it described above, instead of using the equation (5) described above, methods such as determining the value of the damper torque T _D according to the following equation (7) Is applicable.

T _D = E 3 (ω, a, V) (7) where the independent variable a is the acceleration of the vehicle, the independent variable V is the vehicle speed, and the function E 3 is an appropriate monovalent function. The method of implementing each of the above functions is arbitrary, and is usually configured based on table data constituting a data map (graph).

For example, the operation and effect of the present invention can be sufficiently obtained by the above embodiments of the present invention.

[Brief description of the drawings]

FIG. 1 is a logical hardware configuration diagram of an electric power steering apparatus 100 according to an embodiment of the present invention.

FIG. 2 is a control block diagram showing a logical outline of a control method of the electric power steering apparatus 100.

FIG. 3 is a control block diagram of a target value generation unit of the electric power steering device 100.

FIG. 4 is a flowchart (first half) of a “target value calculation processing program” that implements a target value generation unit of the electric power steering device 100;

FIG. 5 is a flowchart (second half) of a “target value calculation processing program” that implements a target value generation unit of the electric power steering device 100.

6 is a graph illustrating a hysteresis curve used for calculating a reaction force command value of the electric power steering device 100. FIG.

FIG. 7 is a graph illustrating the behavior of a steering wheel (steering wheel 10) of the electric power steering device 100.

FIG. 8 is a control block diagram illustrating an outline of a general control method of an electric power steering device using a steering torque control means (62) set to ensure robustness and stability.

9 is a control block diagram of a control method (example 1) of a conventional target value generation means (corresponding to 61 in FIG. 8).

FIG. 10 shows a conventional target value generating means (corresponding to 61 in FIG. 8).
3 is a control block diagram of the control method (Example 2).

11 is a graph illustrating the behavior of a steering wheel of an electric power steering device using a conventional target value generating means (the control method (Example 2) of FIG. 10).

FIG. 12 is a control block diagram illustrating another control method in another conventional electric power steering device.

[Explanation of symbols]

402: LPF processing section (detection angular velocity vibration mitigation means) 403: steering angle estimation processing section (steering angle estimation means) 404: turning-up / turn-back determining section (rotation direction determining means) 405: reaction force command value calculating section (basic) Term generating means) 406 Damper gain multiplying section (damper term generating means) 407 Torque command value adding section 408 Target value correction processing section (command value vibration reducing means)

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme court ゛ (Reference) B62D 119: 00 B62D 119: 00 (72) Inventor Eiichi Ono 41 No. 1 Inside Toyota Central Research Laboratories Co., Ltd. (72) Inventor Shoji Asai 41-Chome Yokomichi, Nagakute-cho, Aichi-gun, Aichi F-term (reference) 3D032 CC03 CC48 DA03 DA09 DA15 DA23 DD05 DD17 EB04 EB12 EC23 EC29 GG01 3D033 CA03 CA13 CA16 CA17 CA19 CA21

Claims (6)

[Claims] 1. A motor for applying assist torque to a steering mechanism for assisting steering of a vehicle, a torque sensor for detecting a steering torque q applied to a steering wheel by a driver, and detecting a traveling speed (vehicle speed V) of the vehicle. Vehicle speed sensor,
An electric power steering apparatus comprising: a steering angle sensor for detecting a rotation angle (steering angle θ) of the steering wheel; and a motor control device for driving and controlling the motor, wherein a steering angle compensation based on a detected value of the steering angle θ is provided. A steering angle estimating means for calculating an estimated value Θ of the steering angle θ at or near the present at a period shorter than the output cycle of the steering angle sensor substantially periodically by an external process, based on at least the estimated value Θ And the steering torque q
And target value generating means but for calculating a target value h to be reached, as the steering torque q to follow the target value h, and a steering torque control means for determining a command value I _A of the drive current of the motor An electric power steering device, comprising: 2. The system according to claim 1, wherein the target value generating means further calculates the target value h based on at least one of the rotational angular velocity ω of the steering wheel and the vehicle speed V. Item 2. The electric power steering device according to item 1. 3. A detection angular velocity vibration mitigation means for removing a vibration component in a specific frequency band of the rotational angular velocity of the steering wheel calculated based on the detected value of the steering angle θ, and the steering angle estimating means. 3. The electric power steering apparatus according to claim 1, wherein the estimated value Θ is calculated based on the rotational angular velocity ω calculated by the detected angular velocity vibration mitigation means. Wherein said target value h, by shortening using the command value I _A, or a related value x of the output cycle predetermined interpolation / extrapolation, the output value h, the I _A or x 1
The electric power steering apparatus according to any one of claims 1 to 3, further comprising "command value vibration reducing means" for reducing a fluctuation amount per output cycle. 5. A basic value generating means for generating a basic term that depends on at least the estimated value Θ based on a predetermined hysteresis characteristic, and at least depends on a rotational angular velocity ω of the steering wheel. The electric power steering apparatus according to any one of claims 1 to 4, wherein damper term generation means for generating a damper term are provided independently or in parallel with each other. 6. The target value generation means or the steering torque control means uses a transfer function set to ensure robust stability against a model error and a disturbance of a control model of the electric power steering device. Te, the target value h, the command value I _a or electric power steering apparatus according to any one of claims 1 to 5, characterized in that determining these related values x.