JP2008273226A - Vehicular steering control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vehicular steering control device capable of correctly detecting the occurrence of disturbance by an inexpensive and simple constitution even in a range of small steering torque, suppressing the disturbance, and performing the consistent control of a vehicle. <P>SOLUTION: The vehicular steering control device comprises a road surface reaction torque detector 12 for detecting the actual road surface reaction torque Talign, a vehicle speed detector 10 for detecting a vehicle speed V, a steering wheel angle detector 5 for detecting a steering wheel angle Theta, a target road surface reaction torque computation unit 19 for computing target road surface reaction torque Talign_ref, and a disturbance occurrence detection unit 20 for outputting a disturbance state signal Dist(s) by detecting the disturbance from the actual road surface reaction torque Talign and the target road surface reaction torque Talign_ref. An assist torque computation unit 21 for computing assist torque Tassist includes a viscosity compensation unit 32 or a reaction force compensation unit 33 for compensating the assist torque Tassist. The viscosity compensation unit 32 or the reaction force compensation unit 33 computes compensation torque based on a disturbance state signal Dist(s). <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a vehicle steering control device provided with a disturbance occurrence detection means for detecting the occurrence of a disturbance to a vehicle.

In general, when a vehicle traveling straight ahead receives a strong crosswind or enters a saddle road surface or a cant road surface, the steering wheel may be taken due to disturbance (disturbance torque) to the vehicle, and the steering stability may be impaired. .
Therefore, for example, in order to assist the steering torque with an electric motor and perform vehicle stabilization control, it is necessary to accurately detect the occurrence of a disturbance.

  In order to detect the occurrence of a disturbance, a conventional electric power steering apparatus detects a steering torque of a steering system and outputs a steering torque signal, and detects a steering angle of the steering system to detect a steering angle signal. The sign (direction) of the steering angle signal and the steering rotation speed signal coincides with the steering angle detection means for outputting the steering rotation speed detection means for detecting the steering rotation speed of the steering system and outputting the steering rotation speed signal. When the sign (direction) of the steering torque signal does not match, disturbance steering determination means for determining the disturbance steering state is provided, and the steering torque is corrected so as to suppress the disturbance (see, for example, Patent Document 1). ).

  In addition, the conventional electric power steering apparatus has a steering angle change which is a ratio of the steering angle change amount obtained by the steering angle change amount calculating means and the steering torque change amount obtained by the steering torque change amount calculating means. Means for determining a change ratio with respect to steering torque, a disturbance occurrence determination means for determining that a disturbance has occurred with respect to the vehicle when the obtained steering angle change with respect to steering torque change ratio is equal to or greater than a predetermined value; Motor control means for driving and controlling the electric motor so as to increase the steering assist force in a direction to cancel the influence of the disturbance in response to the determination means that the disturbance has occurred (for example, , See Patent Document 2).

  Further, the conventional vehicle steering apparatus includes at least one of a yaw rate sensor and a lateral acceleration sensor, and includes vehicle behavior detecting means for detecting a disturbance to the vehicle in accordance with the yaw rate or the lateral acceleration, and a detection value from the vehicle behavior detecting means. Based on the above, the auxiliary reaction force torque is generated in a direction to suppress the disturbance (see, for example, Patent Document 3).

JP-A-8-268309 JP 2002-264832 A JP 2000-25630 A

In the conventional electric power steering apparatus described in Patent Document 1, the occurrence of a disturbance to the vehicle is detected when the signs of the steering angle signal and the steering rotation speed signal match and the signs of the steering torque signal do not match. is doing. Further, in the conventional electric power steering apparatus described in Patent Document 2, the occurrence of disturbance is detected based on the change amount of the steering angle and the steering torque.
However, since the steering torque includes a friction torque generated in the steering system, there is a problem in that the occurrence of disturbance cannot be accurately detected in a region where the steering torque is small.

In addition, the conventional vehicle steering apparatus described in Patent Document 3 requires a yaw rate sensor that detects yaw rate or a lateral acceleration sensor that detects lateral acceleration in order to detect the occurrence of disturbance.
However, there are many light vehicles and small vehicles with short wheel bases in vehicles whose vehicle behavior is disturbed by the occurrence of disturbances, and there is a problem that it is difficult to add a sensor in terms of cost. Further, there is a problem that the configuration of the apparatus becomes complicated by adding the sensor.

  An object of the present invention is to solve the above-described problems, and an object of the present invention is to accurately detect the occurrence of a disturbance with an inexpensive and simple configuration even in a region where the steering torque is small. An object of the present invention is to provide a vehicle steering control device that can control the stabilization of a vehicle while suppressing disturbance.

  The vehicle steering control device according to the present invention includes an assist torque calculating means for calculating an assist torque for assisting a steering torque by a driver of the vehicle, and a road surface for detecting an actual road surface reaction force torque that a vehicle wheel receives from the road surface. Reaction force torque detection means, vehicle speed detection means for detecting the vehicle speed of the vehicle, handle angle detection means for detecting the handle angle of the handle of the vehicle, and target road surface for calculating the target road surface reaction force torque based on the vehicle speed and the handle angle A reaction force torque calculating means, and a disturbance occurrence detecting means for comparing the signs of the actual road surface reaction force torque and the target road surface reaction force torque to detect the occurrence of a disturbance to the vehicle and to output a disturbance state signal, The assist torque calculation means includes at least one of a viscosity compensation means and a reaction force compensation means for calculating a compensation torque for compensating the assist torque, and the viscosity compensation At least one of the stages and the reaction force compensating means, based on the disturbance state signal, and calculating a compensation torque to suppress the disturbance.

According to the vehicle steering control apparatus of the present invention, the disturbance occurrence detecting means detects the occurrence of disturbance on the vehicle by comparing the signs of the actual road surface reaction force torque not including the friction torque and the target road surface reaction force torque. . The assist torque calculating means includes at least one of a viscosity compensating means and a reaction force compensating means for calculating a compensation torque for compensating the assist torque, and at least one of the viscosity compensating means and the reaction force compensating means is a disturbance state signal. Based on the above, the compensation torque is calculated so as to suppress the disturbance.
Therefore, even in a region where the steering torque is small, it is possible to accurately detect the occurrence of a disturbance with an inexpensive and simple configuration, and it is possible to control the vehicle while suppressing the disturbance.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the drawings, the same or corresponding members and parts will be described with the same reference numerals.
In the following embodiments, a case will be described in which the vehicle steering apparatus is mounted on an automobile.

Embodiment 1 FIG.
1 is a configuration diagram showing a steering mechanism 1 of a vehicle steering control apparatus according to Embodiment 1 of the present invention.
In FIG. 1, a steering mechanism 1 includes a handle 2, a steering shaft 3, a steering gear box 4, a handle angle detector 5 (handle angle detection means), a torque sensor 6, and an assist motor 7 (motor). Rack and pinion mechanism 8, tire 9 (wheel), EPS (Electric Power Steering) control unit 100 (hereinafter abbreviated as "control unit 100"), vehicle speed detector 10 (vehicle speed detection means), motor speed A detector 11 (motor speed detecting means) and a road surface reaction force torque detector 12 (road surface reaction torque detecting means) are provided.

Here, electric power is supplied to the steering mechanism 1 from a power supply device (not shown).
The handle angle detector 5, the torque sensor 6, the assist motor 7, the vehicle speed detector 10, the motor speed detector 11, and the road surface reaction force torque detector 12 are electrically connected to the control unit 100 via cables. ing.

A steering wheel 2 that is steered by a driver of the automobile is connected to one end of a steering shaft 3. In addition, a handle angle detector 5 that detects the handle angle Theta and outputs it to the control unit 100 is attached to the handle 2.
A torque sensor 6 that detects a steering torque Thdl caused by the driver's steering and outputs it to the control unit 100 is attached to the steering shaft 3. An electric assist motor 7 that generates an assist torque Tassist for assisting the steering torque Thdl is attached to the steering shaft 3 via a reduction gear (not shown).

The other end of the steering shaft 3 is connected to a steering gear box 4 that amplifies the combined torque (a torque obtained by adding the steering torque Thdl and the assist torque Tassist) several times.
A tire 9 is attached to the steering gear box 4 via a rack and pinion mechanism 8 that converts rotational motion into reciprocating motion.

The vehicle speed detector 10 detects the vehicle speed V of the vehicle and outputs it to the control unit 100. The motor speed detector 11 detects the motor speed (rotational speed) Smtr of the assist motor 7 and outputs it to the control unit 100. Further, the road surface reaction torque detector 12 detects the actual road surface reaction torque Talign that the tire 9 receives from the road surface, and outputs it to the control unit 100.
The control unit 100 receives the steering wheel angle Theta, the steering torque Thdl, the vehicle speed V, the motor speed Smtr, the actual road surface reaction force torque Talign, the motor detection current Imtr of the assist motor 7, and the motor detection voltage Vmtr of the assist motor 7. .
Further, the control unit 100 calculates a target current value for causing the assist motor 7 to generate the assist torque Tassist based on the above input, and outputs a motor drive current Idrive to the assist motor 7.

Here, the steering shaft reaction force torque Ttran generated in the steering shaft 3 is a road surface reaction force torque converted to the steering shaft 3. Further, the steering shaft reaction force torque Ttran is a value obtained by adding the actual road surface reaction force torque Talign and the total friction torque Tfric (not shown).
The overall friction torque Tfric is a friction torque generated in the entire steering mechanism 1 including the assist motor 7.
That is, the steering shaft reaction force torque Ttran is expressed by the following equation (1).

    Ttran = Talign + Tfric (1)

The overall friction torque Tfric is a value obtained by adding a value obtained by multiplying the motor friction torque Tmfric by a gear ratio Ggear of a reduction gear provided between the assist motor 7 and the steering shaft 3 and the shaft friction torque Tfrp. .
The motor friction torque Tmfric is a friction torque generated only in the assist motor 7, and the shaft friction torque Tfrp is a friction torque generated in the steering mechanism 1 without considering the assist motor 7.
The relationship between these friction torques is expressed by the following equation (2).

    Tfric = Tmfric · Ggear + Tfrp (2)

  This vehicle steering control device has a main function of detecting a steering torque Thdl when the driver steers the steering wheel 2 with the torque sensor 6 and generating an assist torque Tassist corresponding to the steering torque Thdl.

Further, mechanically, the sum of the steering torque Thdl and the assist torque Tassist rotates the steering shaft 3 against the steering shaft reaction force torque Ttran. In addition, when the steering wheel 2 is steered, inertia torque generated by the inertia of the assist motor 7 also acts.
Therefore, when the inertia torque of the assist motor 7 is J · dω / dt, the steering shaft reaction torque Ttran is expressed by the following equation (3).

    Ttran = Thdl + Tassist−J · dω / dt (3)

  The assist torque Tassist by the assist motor 7 is expressed by the following equation (4) using the gear ratio Ggear of the reduction gear and the motor detection current Imtr, where the torque constant of the assist motor 7 is Kt.

    Tassist = Ggear / Kt / Imtr (4)

  Further, the steering shaft reaction force torque Ttran is expressed by the following equation (5) by modifying the above equation (1) using the above equation (2).

    Ttran = Talign + (Tmfric · Ggear + Tfrp) (5)

The control unit 100 controls the current so that the calculated target current value matches the motor detection current Imtr, and outputs a motor drive current Idrive.
The assist motor 7 generates torque obtained by multiplying the motor drive current Idrive by the torque constant Kt and the gear ratio Ggear of the reduction gear, and assists the steering torque Thdl by the driver.

FIG. 2 is a block diagram showing the control unit 100 of FIG. 1 together with the assist motor 7.
In FIG. 2, the control unit 100 includes a vehicle speed detection unit 13, a steering torque detection unit 14, a motor speed detection unit 15, a motor acceleration detection unit 16, a handle angle detection unit 17, and a road surface reaction force torque detection unit 18. A target road surface reaction torque calculation unit 19 (target road surface reaction force torque calculation unit), a disturbance generation detection unit 20 (disturbance generation detection unit), an assist torque calculation unit 21 (assist torque calculation unit), and a motor current calculation A unit 22, a motor current detection unit 23, a comparison unit 24, and a motor drive unit 25 are included.
Here, the control unit 100 is constituted by a microprocessor (not shown) having a CPU and a memory storing a program, and each block constituting the control unit 100 is stored as software in the memory. .

The vehicle speed detector 13 receives the vehicle speed V output from the vehicle speed detector 10 and outputs a vehicle speed signal V (s). The steering torque detector 14 receives the steering torque Thdl output from the torque sensor 6 and outputs a steering torque signal Thdl (s).
The motor speed detector 15 receives the motor speed Smtr output from the motor speed detector 11 and outputs a motor speed signal Smtr (s). The motor acceleration detector 16 differentiates the motor speed signal Smtr (s) and outputs a motor acceleration signal Amtr (s).
The motor speed detection unit 15 is based on the motor detection current signal Imtr (s) output from the motor current detection unit 23 and the motor detection voltage signal Vmtr (s) output from the motor voltage detection unit (not shown). The motor speed signal Smtr (s) may be output.

The handle angle detector 17 receives the handle angle Theta output from the handle angle detector 5 and outputs a handle angle signal Theta (s). The road surface reaction force torque detector 18 receives the actual road surface reaction force torque Talign output from the road surface reaction force torque detector 12 and outputs an actual road surface reaction torque signal Talign_act (s).
The road surface reaction torque detector 12 for detecting the actual road reaction torque Talign is, for example, a load cell (not shown) attached to the tire 9, and the deformation of the strain gauge provided in the load cell is changed to the actual road reaction torque Torig. Output as.

The target road surface reaction torque calculation unit 19 has a vehicle speed / handle angle-target road surface reaction torque map in which the relationship between the vehicle speed V and the handle angle Theta and the target road surface reaction torque Talign_ref is described.
Based on the vehicle speed signal V (s) from the vehicle speed detection unit 13 and the steering wheel angle signal Theta (s) from the steering wheel angle detection unit 17, the target road surface reaction torque calculation unit 19 calculates the vehicle speed / handle angle-target. A target road surface reaction torque signal Talign_ref (s) is calculated from the road surface reaction torque map.

The disturbance generation detection unit 20 detects the presence or absence of disturbance on the vehicle based on the actual road surface reaction force torque signal Talign_act (s) and the target road surface reaction force torque signal Talign_ref (s), and the disturbance state signal Dist (s ) Is output.
The disturbance occurrence detection unit 20 includes a code comparison unit 26, a ratio calculation unit 27, and a correction unit 28 (correction means).

  The sign comparison unit 26 signifies the actual road surface reaction force torque signal Talign_act (s) from the road surface reaction force torque detection unit 18 and the target road surface reaction force torque signal Talign_ref (s) from the target road surface reaction force torque calculation unit 19. Are detected, and the presence or absence of a disturbance is detected, and a disturbance detection signal Dist_sgn (s) is output.

  That is, the sign comparison unit 26 determines that a disturbance has occurred when the signs of the actual road surface reaction force torque signal Talign_act (s) and the target road surface reaction force torque signal Talign_ref (s) do not match, the disturbance detection signal Dist_sgn (s) ) Is output as “1”. Further, when the signs of the actual road surface reaction force torque signal Talign_act (s) and the target road surface reaction force torque signal Talign_ref (s) match, the disturbance detection signal Dist_sgn ( s) is output as “0”.

  The ratio calculation unit 27 is a ratio between the actual road surface reaction force torque signal Talign_act (s) from the road surface reaction force torque detection unit 18 and the target road surface reaction force torque signal Talign_ref (s) from the target road surface reaction force torque calculation unit 19. And a disturbance torque ratio signal Dist_ratio (s) indicating the degree of occurrence of the disturbance (disturbance state) together with the disturbance detection signal Dist_sgn (s) from the sign comparison unit 26.

Note that the influence of disturbance on the vehicle varies depending on the type of vehicle and the vehicle speed V. Therefore, it is necessary to correct the disturbance torque ratio signal Dist_ratio (s).
The correction unit 28 has a vehicle speed-ratio correction gain map in which the relationship between the vehicle speed V and a ratio correction gain for correcting the disturbance torque ratio signal Dist_ratio (s) is described. This vehicle speed-ratio correction gain map is set according to the type of vehicle. Further, the ratio correction gain may be set to an upper and lower limit value according to the vehicle speed V.
The correction unit 28 calculates a ratio correction gain from this vehicle speed-ratio correction gain map based on the vehicle speed signal V (s) from the vehicle speed detection unit 13, and a disturbance torque ratio signal Dist_ratio (s) from the ratio calculation unit 27. Is multiplied by the ratio correction gain to output the disturbance state signal Dist (s).

The assist torque calculator 21 includes a vehicle speed signal V (s), a steering torque signal Thdl (s), a motor speed signal Smtr (s), a motor acceleration signal Amtr (s), an actual road surface reaction force torque signal Talign_act (s), and The disturbance state signal Dist (s) is input.
The assist torque calculator 21 calculates an assist torque Tassist for assisting the steering torque Thdl based on the above input, and outputs an assist torque signal Tassist (s) for causing the assist motor 7 to generate the assist torque Tassist. To do.

The motor current calculation unit 22 calculates a target current value for causing the assist motor 7 to generate the assist torque Tassist based on the assist torque signal Tassist (s), and outputs a target current signal Idrive (s).
The motor current detector 23 receives the motor detection current Imtr flowing through the assist motor 7 and outputs a motor detection current signal Imtr (s). The comparison unit 24 outputs a deviation between the target current signal Idrive (s) and the motor detection current signal Imtr (s).
The motor drive unit 25 outputs the motor drive current Idrive so that the deviation between the target current signal Idrive (s) and the motor detection current signal Imtr (s) is zero.

FIG. 3 is a block diagram showing in detail the assist torque calculator 21 of FIG.
In FIG. 3, the assist torque calculator 21 includes a disturbance type detector 29 (disturbance type detector), an assist map compensator 30, an inertia compensator 31, a viscosity compensator 32 (viscosity compensator), and a reaction force. A compensation unit 33 (reaction force compensation means) and an addition unit 34 are provided.

  A disturbance type detection unit 29 that detects the type of disturbance according to the generated frequency is a high-pass filter 35 (high-frequency disturbance) that detects that the disturbance to the vehicle is a high-frequency disturbance having a frequency component higher than a predetermined frequency set in advance. Detection means, hereinafter referred to as “HPF35”).

The disturbance type detection unit 29 receives the disturbance state signal Dist (s) from the disturbance occurrence detection unit 20 and outputs a high frequency disturbance state signal Dist_high (s) indicating the degree of occurrence of the high frequency disturbance.
Here, the high-frequency disturbance is a disturbance having a large temporal change, and a signal output as a result of passing the disturbance state signal Dist (s) through the HPF 35 is a high-frequency disturbance state signal Dist_high (s).

The assist map compensation unit 30 has a vehicle speed / steering torque-assist map compensating torque map in which the relationship between the vehicle speed V and the steering torque Thdl and the assist map compensation torque map for assisting the steering torque Thdl is described. .
The assist map compensation unit 30 generates an assist map compensation torque signal map (s) based on the vehicle speed signal V (s) from the vehicle speed detection unit 13 and the steering torque signal Thdl (s) from the steering torque detection unit 14. Output.

The inertia compensation unit 31 has a vehicle speed / motor acceleration-inertia compensation torque map in which the relationship between the vehicle speed V and the motor acceleration Amtr and the inertia compensation torque iner for reducing the inertial feeling of the entire steering system is described.
The inertia compensation unit 31 outputs an inertia compensation torque signal iner (s) based on the vehicle speed signal V (s) from the vehicle speed detection unit 13 and the motor acceleration signal Amtr (s) from the motor acceleration detection unit 16.

The viscosity compensator 32 describes the relationship between the vehicle speed V, the motor speed Smtr and the high frequency disturbance detected by the disturbance type detector 29 and the viscosity compensation torque damp (compensation torque) for suppressing the vibration of the handle 2. It has a vehicle speed, motor speed, high frequency disturbance-viscosity compensation torque map.
The viscosity compensator 32 receives the vehicle speed signal V (s) from the vehicle speed detector 13, the motor speed signal Smtr (s) from the motor speed detector 15, and the high-frequency disturbance state signal Dist_high (s) from the disturbance type detector 29. Based on this, the viscosity compensation torque signal damp (s) is output.

The reaction force compensation unit 33 is a vehicle speed / actual road surface reaction force torque-reaction force compensation torque in which the relationship between the vehicle speed V and the actual road surface reaction force torque Talign and the reaction force compensation torque ret acting in the counter steering direction of the driver is described. Has a map.
The reaction force compensation unit 33 is based on the vehicle speed signal V (s) from the vehicle speed detection unit 13 and the actual road surface reaction force torque signal Talign_act (s) from the road surface reaction force torque detection unit 18. (S) is output.

  The adder 34 receives the assist map compensation torque signal map (s), the inertia compensation torque signal iner (s), the viscosity compensation torque signal damp (s), and the reaction force compensation torque signal ret (s). The adder 34 adds the above inputs and outputs an assist torque signal Tassist (s).

Hereinafter, the viscosity compensation operation of the assist torque calculator 21 according to the first embodiment of the present invention will be described with reference to the flowchart of FIG. 4 together with FIGS.
First, the assist torque calculator 21 reads the disturbance state signal Dist (s) output from the disturbance occurrence detector 20 and stores it in the memory (step S51).

Subsequently, the disturbance type detection unit 29 detects a high frequency disturbance from the disturbance state signal Dist (s), and outputs a high frequency disturbance state signal Dist_high (s) indicating the degree of occurrence of the high frequency disturbance (step S52).
Next, the assist torque calculation unit 21 reads the vehicle speed signal V (s) output from the vehicle speed detection unit 13 and stores it in the memory (step S53), and at the same time, the motor speed signal Smtr (s) output from the motor speed detection unit 15. ) And stored in the memory (step S54).

Subsequently, the viscosity compensation unit 32 calculates the viscosity compensation torque damp based on the high-frequency disturbance state signal Dist_high (s), the vehicle speed signal V (s), and the motor speed signal Smtr (s), and the viscosity compensation torque signal damp ( s) is output (step S55).
Next, the addition unit 34 adds the viscosity compensation torque signal damp (s) and the compensation torque signal from the other compensation units (assist map compensation unit 30, inertia compensation unit 31, reaction force compensation unit 33), and The assist torque signal Tassist (s) is output (step S56), and the process of FIG.

Here, the viscosity compensation unit 32 calculates the viscosity compensation torque damp based on the vehicle speed signal V (s) and the motor speed signal Smtr (s). The viscosity compensation torque damp increases as the motor speed Smtr increases. It becomes.
Further, for example, a high-frequency disturbance from a road surface or the like is a disturbance torque including a frequency component higher than a predetermined frequency set in advance, and affects the motor speed Smtr.
Therefore, when a high-frequency disturbance is detected by the disturbance type detection unit 29, the influence of the high-frequency disturbance is suppressed by correcting the viscosity compensation torque damp according to the high-frequency disturbance state signal Dist_high (s). can do.

Hereinafter, the effect of the viscosity compensation operation of the assist torque calculator 21 will be described with reference to FIG.
FIG. 5 shows a case where a viscosity compensation operation is executed (disturbance suppression control) when a high-frequency disturbance (for example, a disturbance from a road surface) occurs in a vehicle traveling straight ahead, and a case where the viscosity compensation operation is not executed. It is explanatory drawing which shows the relationship between time in (normal control), a steering wheel angle | corner, and viscosity compensation torque damp, respectively.

In FIG. 5, when the vehicle enters the road surface, a high-frequency disturbance from the road surface is generated, the handle 2 is taken, and the handle angle Theta changes (see the dotted circle).
At this time, the viscosity compensation unit 32 increases the viscosity compensation torque damp in order to stop the vibration of the handle 2.
Thereby, compared with the case where viscosity compensation operation | movement is not performed, the handle | steering-wheel angle | corner by a high frequency disturbance can be reduced, and the vibration of the handle | steering-wheel 2 can be suppressed.

According to the vehicle steering control device according to the first embodiment of the present invention, the disturbance occurrence detection unit 20 includes the actual road surface reaction force torque signal Talign_act (s) not including the friction torque and the target road surface reaction force torque signal Talign_ref ( The sign of s) is compared to detect the occurrence of a disturbance to the vehicle, and a disturbance state signal Dist (s) is output. The assist torque calculator 21 includes a viscosity compensator 32 that calculates a viscosity compensation torque damp for compensating the assist torque Tassist. The viscosity compensator 32 detects a disturbance based on the disturbance state signal Dist (s). The viscosity compensation torque damp is calculated so as to be suppressed, and the viscosity compensation torque signal damp (s) is output.
Therefore, even in a region where the steering torque Thdl is small, it is possible to accurately detect the occurrence of a disturbance with an inexpensive and simple configuration, and it is possible to control the vehicle while suppressing the disturbance.

That is, the sign comparison unit 26 of the disturbance occurrence detection unit 20 compares the signs of the actual road surface reaction force torque signal Talign_act (s) and the target road surface reaction force torque signal Talign_ref (s) to detect the presence or absence of disturbance. The disturbance detection signal Dist_sgn (s) is output.
Here, the actual road surface reaction force torque Talign that the tire 9 receives from the road surface does not include friction torque unlike the steering shaft reaction force torque Ttran.
Therefore, the occurrence of disturbance can be accurately detected even in a region where the steering torque Thdl is small. In addition, since the vehicle stabilization control can be performed from a region where the degree of occurrence of disturbance is small, it is possible to prevent the driver from feeling uncomfortable at the time of control intervention.
Moreover, since a yaw rate sensor or a lateral acceleration sensor is not required, an inexpensive and simple configuration can be realized.
Further, since the occurrence of a disturbance is detected based on the actual road surface reaction force torque Talign generated in the tire 9, the occurrence of the disturbance is accurately detected even when the vehicle is traveling on a slippery road surface such as a snowy road. be able to.

Further, the ratio calculation unit 27 of the disturbance occurrence detection unit 20 calculates a ratio between the actual road surface reaction force torque signal Talign_act (s) and the target road surface reaction force torque signal Talign_ref (s), and the disturbance detection signal Dist_sgn (s). At the same time, a disturbance torque ratio signal Dist_ratio (s) indicating the degree of occurrence of the disturbance is output.
Therefore, the degree of occurrence of disturbance can be accurately calculated, and as a result, vehicle stabilization control can be performed appropriately.

The correction unit 28 of the disturbance occurrence detection unit 20 calculates a ratio calculation gain based on the vehicle speed signal V (s), multiplies the disturbance torque ratio signal Dist_ratio (s) by the ratio calculation gain, and outputs the disturbance state signal Dist. (S) is output.
Therefore, the vehicle stabilization control can be performed more appropriately according to the vehicle speed V.

The disturbance type detection unit 29 of the assist torque calculation unit 21 includes an HPF 35 that detects that the disturbance to the vehicle is a high-frequency disturbance including a frequency component higher than a predetermined frequency set in advance, and includes a disturbance generation detection unit 20. The high-frequency disturbance state signal Dist_high (s) indicating the degree of occurrence of the high-frequency disturbance is output.
The viscosity compensation unit 32 of the assist torque calculation unit 21 is for suppressing vibration of the steering wheel 2 based on the vehicle speed signal V (s), the motor speed signal Smtr (s), and the high-frequency disturbance state signal Dist_high (s). The viscosity compensation torque damp is calculated and a viscosity compensation torque signal damp (s) is output.
Therefore, the type of disturbance can be detected with an inexpensive and simple configuration, and the vehicle stabilization control can be more appropriately performed according to the frequency of occurrence of the disturbance.

The viscosity compensation unit 32 of the first embodiment has a vehicle speed / motor speed / high frequency disturbance-viscosity compensation torque map, and includes a vehicle speed signal V (s), a motor speed signal Smtr (s), and a high frequency disturbance state signal Dist_high. It has been described that the viscosity compensation torque signal damp (s) is output based on (s).
However, the present invention is not limited to this, and the viscosity compensator 32 includes a vehicle speed / motor speed-viscosity compensation torque map in which the relationship between the vehicle speed V and the motor speed Smtr and the viscosity compensation torque damp is described, and high-frequency disturbance and viscosity compensation. You may have the high frequency disturbance-torque correction gain map in which the relationship with the torque correction gain for correcting the torque damp was described.
At this time, the viscosity compensator 32 first calculates the viscosity compensation torque damp based on the vehicle speed signal V (s) and the motor speed signal Smtr (s). Subsequently, the viscosity compensation unit 32 calculates a torque correction gain based on the high-frequency disturbance state signal Dist_high (s). Next, the viscosity compensation unit 32 multiplies the viscosity compensation torque damp by a torque correction gain and outputs the result as a viscosity compensation torque signal damp (s).
Also in this case, the same effect as in the first embodiment can be obtained.

Further, in order to clarify the characteristics of the vehicle steering control device according to the first embodiment, the compensation unit in the assist torque calculation unit 21 is changed to an assist map compensation unit 30, an inertia compensation unit 31, a viscosity compensation unit 32, and an anti-reflection unit. The input signal to the assist torque calculator 21 is also limited to the force compensator 33.
However, the actual assist torque calculator 21 calculates the assist torque Tassist using various signals other than these signals. The vehicle steering apparatus according to the present embodiment can be applied to any vehicle steering apparatus.

Embodiment 2. FIG.
In the first embodiment, the high-frequency disturbance is detected from the disturbance state signal Dist (s) and the influence of the high-frequency disturbance is reduced. However, the present invention is not limited to this, and the low-frequency disturbance is detected from the disturbance state signal Dist (s). The influence of low frequency disturbances may be reduced.

FIG. 6 is a block diagram showing in detail an assist torque calculator 21A of the vehicle steering control apparatus according to Embodiment 2 of the present invention.
In FIG. 6, the assist torque calculation unit 21A replaces the disturbance type detection unit 29, the viscosity compensation unit 32, and the reaction force compensation unit 33 shown in FIG. 3 with a disturbance type detection unit 29A, a viscosity compensation unit 32A, and a reaction force compensation. It has a portion 33A.

  The disturbance type detection unit 29A that detects the type of disturbance according to the generated frequency is a low-pass filter 36 that detects that the disturbance to the vehicle is a low-frequency disturbance having a frequency component lower than a preset predetermined frequency. Frequency disturbance detecting means, hereinafter referred to as “LPF 36”).

The disturbance type detection unit 29A receives the disturbance state signal Dist (s) from the disturbance occurrence detection unit 20, and outputs a low frequency disturbance state signal Dist_low (s) indicating the degree of occurrence of the low frequency disturbance.
Here, the low-frequency disturbance is a disturbance having a small temporal change, and a signal output as a result of passing the disturbance state signal Dist (s) through the LPF 36 is a low-frequency disturbance state signal Dist_low (s).

The viscosity compensation unit 32A has a vehicle speed / motor speed-viscosity compensation torque map in which the relationship between the vehicle speed V and motor speed Smtr and the viscosity compensation torque damp (compensation torque) is described.
The viscosity compensation unit 32A outputs a viscosity compensation torque signal damp (s) based on the vehicle speed signal V (s) from the vehicle speed detection unit 13 and the motor speed signal Smtr (s) from the motor speed detection unit 15.

The reaction force compensation unit 33A is a vehicle speed / actual road surface reaction force torque in which the relationship between the vehicle speed V, the actual road surface reaction torque Talign and the low frequency disturbance detected by the disturbance type detection unit 29A and the reaction force compensation torque ret is described. -It has a low-frequency disturbance-reaction force compensation torque map.
The reaction force compensation unit 33A includes a vehicle speed signal V (s) from the vehicle speed detection unit 13, an actual road surface reaction force torque signal Talign_act (s) from the road surface reaction force torque detection unit 18, and a low frequency disturbance from the disturbance type detection unit 29A. A reaction force compensation torque signal ret (s) is output based on the state signal Dist_low (s).
Other configurations are the same as those in the first embodiment, and the description thereof is omitted.

Hereinafter, the reaction force compensation operation of the assist torque calculation unit 21A according to the second embodiment of the present invention will be described with reference to the flowchart of FIG. 7 together with FIGS.
First, the assist torque calculation unit 21A reads the disturbance state signal Dist (s) output from the disturbance occurrence detection unit 20 and stores it in the memory (step S61).

Subsequently, the disturbance type detection unit 29A detects a low frequency disturbance from the disturbance state signal Dist (s), and outputs a low frequency disturbance state signal Dist_low (s) indicating the degree of occurrence of the low frequency disturbance (step S62).
Next, the assist torque calculator 21A reads the vehicle speed signal V (s) output from the vehicle speed detector 13 and stores it in the memory (step S63), and the actual road surface reaction force output by the road surface reaction torque detector 18. The torque signal Talign_act (s) is read and stored in the memory (step S64).

Subsequently, the reaction force compensation unit 33A calculates the reaction force compensation torque ret based on the low-frequency disturbance state signal Dist_low (s), the vehicle speed signal V (s), and the actual road surface reaction force torque signal Talign_act (s), The reaction force compensation torque signal ret (s) is output (step S65).
Next, the addition unit 34 adds the reaction force compensation torque signal ret (s) and the compensation torque signal from the other compensation units (assist map compensation unit 30, inertia compensation unit 31, viscosity compensation unit 32A), and The assist torque signal Tassist (s) is output (step S66), and the process of FIG.

Here, the reaction force compensation unit 33A calculates the reaction force compensation torque ret based on the vehicle speed signal V (s) and the actual road surface reaction force torque signal Talign_act (s). The reaction force compensation torque ret is calculated based on the actual road surface. The reaction torque Talign increases as the reaction torque Talign increases.
Further, for example, a low-frequency disturbance from a cant road surface or the like is a disturbance torque having a frequency component lower than a predetermined frequency set in advance, and affects the actual road surface reaction force torque Talign.
Therefore, when a low frequency disturbance is detected by the disturbance type detection unit 29A, the low frequency disturbance is corrected by increasing the reaction force compensation torque ret according to the low frequency disturbance state signal Dist_low (s). The influence by can be suppressed.

Hereinafter, the effect of the reaction force compensation operation of the assist torque calculator 21A will be described with reference to FIG.
FIG. 8 shows a case where a reaction force compensation operation is executed (disturbance suppression control) and a reaction force compensation operation when a low-frequency disturbance (for example, a disturbance from a cant road surface) occurs in a vehicle traveling straight ahead. It is explanatory drawing which shows the relationship between time in the case of not performing (normal control), a steering torque, and reaction force compensation torque ret, respectively.

In FIG. 8, when the vehicle enters the cant road surface, a low-frequency disturbance from the cant road surface is generated, and a handle torque is generated (see a broken circle).
At this time, the reaction force compensation unit 33A increases the reaction force compensation torque ret in order to reduce the handle torque.
Thereby, compared with the case where reaction force compensation operation is not performed, the handle torque by a low frequency disturbance can be reduced.

According to the vehicle steering control apparatus according to Embodiment 2 of the present invention, the disturbance type detection unit 29A of the assist torque calculation unit 21A is a low disturbance whose vehicle disturbance includes a frequency component lower than a predetermined frequency set in advance. The low-frequency disturbance state signal Dist_low (s) indicating the degree of occurrence of the low-frequency disturbance is output in response to the disturbance state signal Dist (s) from the disturbance occurrence detection unit 20. .
Further, the reaction force compensation unit 33A of the assist torque calculation unit 21A is based on the vehicle speed signal V (s), the actual road surface reaction force torque signal Talign_act (s), and the high-frequency disturbance state signal Dist_high (s). And the reaction force compensation torque signal ret (s) is output.
Therefore, the type of disturbance can be detected with an inexpensive and simple configuration, and the vehicle stabilization control can be more appropriately performed according to the frequency of occurrence of the disturbance.

It has been described that the disturbance type detection unit 29 of the first embodiment includes the HPF 35 that detects high-frequency disturbances, and the disturbance type detection unit 29A of the second embodiment includes the LPF 36 that detects low-frequency disturbances. However, the present invention is not limited to this, and the disturbance type detection unit may include both HPF and LPF.
As a result, even when a disturbance in which a high-frequency disturbance and a low-frequency disturbance are combined occurs, the viscosity compensation unit 32 calculates the viscosity compensation torque damp according to the high-frequency disturbance, and the reaction force according to the low-frequency disturbance. When the compensation unit 33A calculates the reaction force compensation torque ret, the vehicle stabilization control can be performed more appropriately.

Further, the reaction force compensation unit 33A of the second embodiment has a vehicle speed / actual road surface reaction torque / low frequency disturbance-reaction force compensation torque map, and includes a vehicle speed signal V (s) and an actual road surface reaction force torque signal Talign_act. It has been described that the reaction force compensation torque signal ret (s) is output based on (s) and the high-frequency disturbance state signal Dist_high (s).
However, the reaction force compensation unit 33A is not limited to this, and the reaction force compensation unit 33A is configured to provide the vehicle speed / actual road surface reaction force torque-reaction force compensation torque in which the relationship between the vehicle speed V and the actual road surface reaction force torque Talign and the reaction force compensation torque ret is described. You may have a map and the low frequency disturbance-torque correction gain map in which the relationship between the low frequency disturbance and the torque correction gain for correcting the reaction force compensation torque ret is described.
At this time, the reaction force compensation unit 33A first calculates a reaction force compensation torque ret based on the vehicle speed signal V (s) and the actual road surface reaction force torque signal Talign_act (s). Subsequently, the reaction force compensation unit 33A calculates a torque correction gain based on the low-frequency disturbance state signal Dist_low (s). Next, the reaction force compensation unit 33A multiplies the reaction force compensation torque ret by a torque correction gain, and outputs the result as a reaction force compensation torque signal ret (s).
Also in this case, the same effects as those of the second embodiment can be obtained.

Further, in order to clarify the characteristics of the vehicle steering control device according to the second embodiment, the compensation unit in the assist torque calculation unit 21A includes an assist map compensation unit 30, an inertia compensation unit 31, a viscosity compensation unit 32A, and an anti-compensation unit. The input signal to the assist torque calculation unit 21A is also limited to the force compensation unit 33A.
However, the actual assist torque calculation unit 21A calculates the assist torque Tassist using various signals in addition to these signals. The vehicle steering apparatus according to the present embodiment can be applied to any vehicle steering apparatus.

In addition, the disturbance occurrence detection unit 20 of the first and second embodiments includes a ratio calculation unit 27, and calculates the ratio between the actual road surface reaction force torque signal Talign_act (s) and the target road surface reaction force torque signal Talign_ref (s). By calculating, the degree of occurrence of disturbance is calculated.
However, the present invention is not limited to this, and the disturbance occurrence detection unit 20 may include a deviation calculation unit instead of the ratio calculation unit 27. The deviation calculation unit calculates a deviation between the actual road surface reaction force torque signal Talign_act (s) and the target road surface reaction force torque signal Talign_ref (s), and together with the disturbance detection signal Dist_sgn (s), a disturbance indicating the degree of occurrence of the disturbance. A torque deviation signal Dist_dev (s) is output.
Also in this case, the same effects as those of the first and second embodiments can be obtained.

Further, the disturbance occurrence detection unit 20 does not include the ratio calculation unit 27 and the correction unit 28, and detects the presence / absence of the occurrence of the disturbance and outputs the disturbance state signal Dist (s). May be included.
Further, the disturbance occurrence detection unit 20 has a predetermined threshold at which a ratio or deviation between the actual road surface reaction torque signal Talign_act (s) and the target road surface reaction torque signal Talign_ref (s) is set according to the type of vehicle. The occurrence of a disturbance to the vehicle may be detected when the value exceeds.
In these cases, the configuration of the apparatus can be further simplified.

Embodiment 3 FIG.
FIG. 9 is a block diagram showing the control unit 100B of the vehicle steering control device according to the third embodiment of the present invention together with the assist motor 7. In FIG.
In FIG. 9, the control unit 100B calculates an actual road surface reaction force torque change rate dTalign_act which is a time change rate of the actual road surface reaction force torque Talign, and outputs an actual road surface reaction force torque change rate signal dTalign_act (s). A reaction force torque change rate calculation unit 37 (actual road surface reaction force torque change rate calculation means) is provided.

Further, the control unit 100B replaces the target road surface reaction force torque calculation unit 19 and the disturbance occurrence detection unit 20 shown in FIG. 2 with a target road surface reaction force torque change rate calculation unit 38 (target road surface reaction force torque change rate calculation means). ) And a disturbance occurrence detecting unit 20B.
Note that the configuration of the assist torque calculator 21 is the same as that of the first embodiment described above, and thus detailed description thereof is omitted.

The target road surface reaction force torque change rate calculation unit 38 has a vehicle speed / motor speed-target road surface reaction force torque change rate map in which the relationship between the vehicle speed V and the motor speed Smtr and the target road surface reaction force torque change rate dTalign_ref is described. is doing.
Based on the vehicle speed signal V (s) from the vehicle speed detection unit 13 and the motor speed signal Smtr (s) from the motor speed detection unit 15, the target road surface reaction force torque change rate calculation unit 38. -A target road surface reaction force torque change rate signal dTalign_ref (s) is calculated from the target road surface reaction force torque change rate map.

The disturbance generation detection unit 20B detects the presence or absence of disturbance on the vehicle based on the actual road surface reaction force torque change rate signal dTalign_act (s) and the target road surface reaction force torque change rate signal dTalign_ref (s), and the disturbance state The signal Dist (s) is output.
The disturbance occurrence detection unit 20B includes a sign comparison unit 26B, a ratio calculation unit 27B, and a correction unit 28 (correction means).

  The sign comparison unit 26B includes an actual road reaction force torque change rate signal dTalign_act (s) from the actual road reaction force torque change rate calculation unit 37, and a target road surface reaction force torque change change from the target road reaction force torque change rate calculation unit 38. The sign of the rate signal dTalign_ref (s) is compared, the presence / absence of disturbance is detected, and a disturbance detection signal Dist_sgn (s) is output.

  That is, the sign comparison unit 26B detects that a disturbance has occurred when the sign of the actual road surface reaction force torque change rate signal dTalign_act (s) and the target road surface reaction force torque change rate signal dTalignn_ref (s) do not match. The signal Dist_sgn (s) is output as “1”. Further, when the signs of the actual road surface reaction force torque change rate signal dTalignn_act (s) and the target road surface reaction force torque change rate signal dTalign_ref (s) match, the disturbance is assumed not to occur (normal steering state). The detection signal Dist_sgn (s) is output as “0”.

  The ratio calculation unit 27B is configured to output the actual road surface reaction force torque change rate signal dTalign_act (s) from the actual road surface reaction force torque change rate calculation unit 37 and the target road surface reaction force torque change rate calculation unit 38. The ratio with the rate signal dTalign_ref (s) is calculated, and a disturbance torque ratio signal Dist_ratio (s) indicating the degree of occurrence of the disturbance (disturbance state) is output together with the disturbance detection signal Dist_sgn (s) from the sign comparison unit 26B. .

Note that the influence of disturbance on the vehicle varies depending on the type of vehicle and the vehicle speed V. Therefore, it is necessary to correct the disturbance torque ratio signal Dist_ratio (s).
The correction unit 28 has a vehicle speed-ratio correction gain map in which the relationship between the vehicle speed V and a ratio correction gain for correcting the disturbance torque ratio signal Dist_ratio (s) is described. This vehicle speed-ratio correction gain map is set according to the type of vehicle. Further, the ratio correction gain may be set to an upper and lower limit value according to the vehicle speed V.
The correction unit 28 calculates a ratio correction gain from the vehicle speed-ratio correction gain map based on the vehicle speed signal V (s) from the vehicle speed detection unit 13, and a disturbance torque ratio signal Dist_ratio (s) from the ratio calculation unit 27B. Is multiplied by the ratio correction gain to output the disturbance state signal Dist (s).

The assist torque calculator 21 includes a vehicle speed signal V (s), a steering torque signal Thdl (s), a motor speed signal Smtr (s), a motor acceleration signal Amtr (s), an actual road surface reaction force torque signal Talign_act (s), and The disturbance state signal Dist (s) is input.
The assist torque calculator 21 calculates an assist torque Tassist for assisting the steering torque Thdl based on the above input, and outputs an assist torque signal Tassist (s) for causing the assist motor 7 to generate the assist torque Tassist. To do.

The disturbance type detection unit 29 of the assist torque calculation unit 21 receives the disturbance state signal Dist (s) from the disturbance generation detection unit 20B and outputs a high-frequency disturbance state signal Dist_high (s) indicating the degree of occurrence of the high-frequency disturbance. The viscosity compensation unit 32 also includes a vehicle speed signal V (s) from the vehicle speed detection unit 13, a motor speed signal Smtr (s) from the motor speed detection unit 15, and a high-frequency disturbance state signal Dist_high (s) from the disturbance type detection unit 29. ) To output the viscosity compensation torque signal damp (s).
The specific operation is the same as that of the first embodiment described above, and detailed description thereof is omitted.

According to the vehicle steering control apparatus according to the third embodiment of the present invention, the sign comparison unit 26B of the disturbance occurrence detection unit 20B includes the actual road surface reaction force torque change rate signal dTalignnact (s) and the target road surface reaction force torque change. The sign of the rate signal dTalign_ref (s) is compared, the presence / absence of disturbance is detected, and a disturbance detection signal Dist_sgn (s) is output.
Here, the actual road surface reaction force torque Talign that the tire 9 receives from the road surface does not include friction torque unlike the steering shaft reaction force torque Ttran.
Therefore, the occurrence of disturbance can be accurately detected even in a region where the steering torque Thdl is small. In addition, since the vehicle stabilization control can be performed from a region where the degree of occurrence of disturbance is small, it is possible to prevent the driver from feeling uncomfortable at the time of control intervention.

Moreover, since a yaw rate sensor or a lateral acceleration sensor is not required, an inexpensive and simple configuration can be realized.
In addition, since the handle angle detector 5 that detects the handle angle Theta and outputs it to the control unit 100B becomes unnecessary, the configuration of the apparatus can be further simplified.
In addition, by using the rate of change in the road surface reaction torque, it is possible to detect the occurrence of a disturbance at an earlier stage and to perform vehicle stabilization control at an earlier stage.

Further, the ratio calculation unit 27B of the disturbance occurrence detection unit 20B calculates the ratio between the actual road surface reaction force torque change rate signal dTalignn_act (s) and the target road surface reaction force torque change rate signal dTalignn_ref (s), and generates a disturbance detection signal. A disturbance torque ratio signal Dist_ratio (s) indicating the degree of occurrence of disturbance is output together with Dist_sgn (s).
Therefore, the degree of occurrence of disturbance can be accurately calculated, and as a result, vehicle stabilization control can be performed appropriately.

Embodiment 4 FIG.
In the third embodiment, the high-frequency disturbance is detected from the disturbance state signal Dist (s) and the influence of the high-frequency disturbance is reduced. However, the present invention is not limited to this, and the low-frequency disturbance is detected from the disturbance state signal Dist (s). The influence of low frequency disturbances may be reduced.
Hereinafter, a process for detecting a low-frequency disturbance from the disturbance state signal Dist (s) and reducing the influence of the low-frequency disturbance will be described.

Since the configuration of the vehicle steering control apparatus according to the fourth embodiment of the present invention is the same as that of the third embodiment described above, detailed description thereof is omitted. Note that the assist torque calculation unit has the same configuration as the assist torque calculation unit 21A of the second embodiment described above.
The disturbance generation detection unit 20B detects the presence or absence of disturbance on the vehicle based on the actual road surface reaction force torque change rate signal dTalign_act (s) and the target road surface reaction force torque change rate signal dTalign_ref (s), and the disturbance state The signal Dist (s) is output.

The assist torque calculator 21A includes a vehicle speed signal V (s), a steering torque signal Thdl (s), a motor speed signal Smtr (s), a motor acceleration signal Amtr (s), an actual road surface reaction force torque signal Talign_act (s), and The disturbance state signal Dist (s) is input.
The assist torque calculator 21A calculates an assist torque Tassist for assisting the steering torque Thdl based on the above input, and outputs an assist torque signal Tassist (s) for causing the assist motor 7 to generate the assist torque Tassist. To do.

The disturbance type detection unit 29A of the assist torque calculation unit 21A receives the disturbance state signal Dist (s) from the disturbance occurrence detection unit 20B and outputs a low frequency disturbance state signal Dist_low (s) indicating the degree of occurrence of the low frequency disturbance. To do. Further, the reaction force compensation unit 33A includes a vehicle speed signal V (s) from the vehicle speed detection unit 13, an actual road surface reaction force torque signal Talign_act (s) from the road surface reaction force torque detection unit 18, and a low level from the disturbance type detection unit 29A. A reaction force compensation torque signal ret (s) is output based on the frequency disturbance state signal Dist_low (s).
The specific operation is the same as that of the above-described second embodiment, and thus detailed description thereof is omitted.

  According to the vehicle steering control apparatus of the fourth embodiment of the present invention, the same effects as those of the third embodiment can be obtained.

The disturbance type detection unit 29 of the third embodiment described above detects a high frequency disturbance, and the disturbance type detection unit 29A of the fourth embodiment detects a low frequency disturbance. However, the present invention is not limited to this. The disturbance type detection unit may detect both high-frequency disturbances and low-frequency disturbances.
As a result, even when a disturbance in which a high-frequency disturbance and a low-frequency disturbance are combined occurs, the viscosity compensation unit 32 calculates the viscosity compensation torque damp according to the high-frequency disturbance, and the reaction force according to the low-frequency disturbance. When the compensation unit 33A calculates the reaction force compensation torque ret, the vehicle stabilization control can be performed more appropriately.

In addition, the disturbance occurrence detection unit 20B of the third and fourth embodiments described above includes the actual road surface reaction force torque signal Talign_act (s), the target road surface reaction force torque signal Talign_ref (s), and the actual road surface reaction force torque change rate signal dTalign_act ( s) and the target road surface reaction force torque change rate signal dTalign_ref (s) may be combined to calculate the degree of occurrence of the disturbance.
At this time, the control unit 100B includes the handle angle detection unit 17 and the target road surface reaction force torque calculation unit 19 shown in the first embodiment.
In this case, the same effects as those of the third and fourth embodiments can be obtained.

Further, the disturbance occurrence detection unit 20B in the third and fourth embodiments includes a ratio calculation unit 27B, and includes an actual road surface reaction force torque change rate signal dTalign_act (s) and a target road surface reaction force torque change rate signal dTalign_ref (s). The degree of occurrence of the disturbance is calculated by calculating the ratio.
However, the present invention is not limited to this, and the disturbance occurrence detection unit 20B may include a deviation calculation unit instead of the ratio calculation unit 27B. The deviation calculation unit calculates a deviation between the actual road surface reaction force torque change rate signal dTalign_act (s) and the target road surface reaction force torque change rate signal dTalign_ref (s), and generates a disturbance along with the disturbance detection signal Dist_sgn (s). A disturbance torque deviation signal Dist_dev (s) indicating the degree is output.
In this case, the same effects as those of the third and fourth embodiments can be obtained.

In addition, the disturbance occurrence detection unit 20B does not include the ratio calculation unit 27B and the correction unit 28, and detects the presence / absence of the occurrence of the disturbance and outputs the disturbance state signal Dist (s). May be included.
In addition, the disturbance occurrence detection unit 20B sets the ratio or deviation between the actual road surface reaction force torque change rate signal dTalign_act (s) and the target road surface reaction force torque change rate signal dTalign_ref (s) according to the type of vehicle. The occurrence of a disturbance to the vehicle may be detected when a predetermined threshold is exceeded.
In these cases, the configuration of the apparatus can be further simplified.

Further, the road surface reaction force torque detector 12 of the first to fourth embodiments described above is a load cell attached to the tire 9, and the deformation of the strain gauge provided in the load cell is output as the actual road surface reaction force torque Talign. .
However, the present invention is not limited to this, and the road surface reaction force torque detector may calculate the actual road surface reaction force torque Talign by a method disclosed in, for example, Japanese Patent Application Laid-Open No. 2003-312521.
In this case, the road surface reaction force torque detector first calculates the steering shaft reaction force torque Ttran from the steering torque Thdl and the motor detection current Imtr. Subsequently, the steering shaft reaction force torque Ttran is passed through a low-pass filter to calculate an actual road surface reaction force torque Talign. The time constant of the low-pass filter is calculated according to the vehicle speed V and the motor speed Smtr.
Also in this case, the same effects as those of the first to fourth embodiments can be obtained.

It is a block diagram which shows the steering mechanism of the steering control apparatus for vehicles which concerns on Embodiment 1 of this invention. It is a block diagram which shows the control unit of FIG. 1 with an assist motor. It is a block diagram which shows the assist torque calculating part of FIG. 2 in detail. It is a flowchart which shows the viscosity compensation operation | movement of the assist torque calculating part which concerns on Embodiment 1 of this invention. FIG. 6 is an explanatory diagram showing the relationship between time, steering angle, and viscosity compensation torque when a viscosity compensation operation is performed and when a viscosity compensation operation is not performed when a high-frequency disturbance occurs in a vehicle traveling straight ahead. is there. It is a block diagram which shows in detail the assist torque calculating part of the steering control apparatus for vehicles which concerns on Embodiment 2 of this invention. It is a flowchart which shows the reaction force compensation operation | movement of the assist torque calculating part which concerns on Embodiment 2 of this invention. The relationship between time, handle torque, and reaction force compensation torque when the reaction force compensation operation is executed and when the reaction force compensation operation is not executed when a low-frequency disturbance occurs in a vehicle traveling straight ahead. It is explanatory drawing shown. It is a block diagram which shows the control unit of the steering control apparatus for vehicles which concerns on Embodiment 3 of this invention with an assist motor.

Explanation of symbols

  2 handle, 5 handle angle detector (handle angle detection means), 7 assist motor (motor), 9 tire (wheel), 10 vehicle speed detector (vehicle speed detection means), 11 motor speed detector (motor speed detection means), 12 road surface reaction force torque detector (road surface reaction force torque detection means), 19 target road surface reaction torque calculation unit (target road surface reaction torque calculation unit), 20, 20B disturbance generation detection unit (disturbance generation detection unit), 21, 21A Assist torque calculator (assist torque calculator), 28 Corrector (corrector), 29, 29A Disturbance type detector (disturbance type detector), 32, 32A Viscosity compensator (viscosity compensator), 33, 33A Force compensation unit (reaction force compensation means), 35 high pass filter (high frequency disturbance detection means), 36 low pass filter (low frequency disturbance detection means), 37 actual path Surface reaction force torque change rate calculation unit (actual road surface reaction force torque change rate calculation means), 38 Target road surface reaction force torque change rate calculation unit (target road surface reaction force torque change rate calculation means), damp Viscosity compensation torque (compensation torque) , Dist (s) Disturbance state signal, dTalign_act actual road surface reaction torque change rate, dTalign_ref target road reaction torque change rate, ret reaction force compensation torque (compensation torque), Smtr motor speed, Talign actual road reaction torque, Talig_ref target Road reaction torque, Tassist assist torque, Thdl steering torque, Theta steering wheel angle, V vehicle speed.

Claims (11)

An assist torque calculating means for calculating an assist torque for assisting a steering torque by a driver of the vehicle;
Road surface reaction force torque detecting means for detecting actual road surface reaction force torque received by the vehicle wheel from the road surface;
Vehicle speed detecting means for detecting the vehicle speed of the vehicle;
A handle angle detecting means for detecting a handle angle of the handle of the vehicle;
A target road surface reaction torque calculating means for calculating a target road surface reaction torque based on the vehicle speed and the steering wheel angle;
A disturbance occurrence detection means for comparing the sign of the actual road surface reaction force torque and the target road surface reaction force torque, detecting the occurrence of a disturbance to the vehicle, and outputting a disturbance state signal;
The assist torque calculating means includes
Including at least one of a viscosity compensation means and a reaction force compensation means for calculating a compensation torque for compensating the assist torque,
At least one of the viscosity compensation unit and the reaction force compensation unit calculates the compensation torque so as to suppress the disturbance based on the disturbance state signal.   2. The vehicle according to claim 1, wherein the viscosity compensation unit or the reaction force compensation unit calculates the compensation torque in accordance with a deviation between the actual road surface reaction force torque and the target road surface reaction force torque. Steering control device.   2. The vehicle according to claim 1, wherein the viscosity compensation unit or the reaction force compensation unit calculates the compensation torque according to a ratio between the actual road surface reaction force torque and the target road surface reaction force torque. Steering control device.   The vehicle steering system according to claim 2 or 3, further comprising a correction unit that corrects a deviation or a ratio between the actual road surface reaction force torque and the target road surface reaction force torque based on the vehicle speed. Control device. An assist torque calculating means for calculating an assist torque for assisting a steering torque by a driver of the vehicle;
Road surface reaction force torque detecting means for detecting actual road surface reaction force torque received by the vehicle wheel from the road surface;
An actual road surface reaction force torque change rate calculating means for calculating an actual road surface reaction force torque change rate that is a time change rate of the actual road surface reaction force torque;
Vehicle speed detecting means for detecting the vehicle speed of the vehicle;
Motor speed detecting means for detecting the motor speed of the motor that generates the assist torque;
Target road surface reaction force torque change rate calculating means for calculating a target road surface reaction force torque change rate based on the vehicle speed and the motor speed;
Comparing the sign of the actual road surface reaction force torque change rate with the target road surface reaction force torque change rate, detecting the occurrence of a disturbance to the vehicle, and providing a disturbance generation detecting means for outputting a disturbance state signal,
The assist torque calculating means includes
Including at least one of a viscosity compensation means and a reaction force compensation means for calculating a compensation torque for compensating the assist torque,
At least one of the viscosity compensation unit and the reaction force compensation unit calculates the compensation torque so as to suppress the disturbance based on the disturbance state signal.   6. The viscosity compensation means or the reaction force compensation means calculates the compensation torque in accordance with a deviation between the actual road surface reaction force torque change rate and the target road surface reaction force torque change rate. The vehicle steering control device described in 1.   6. The viscosity compensation means or the reaction force compensation means calculates the compensation torque in accordance with a ratio between the actual road surface reaction force torque change rate and the target road surface reaction force torque change rate. The vehicle steering control device described in 1.   The correction means which correct | amends the deviation or ratio of the said actual road surface reaction force torque change rate and the said target road surface reaction force torque change rate based on the said vehicle speed is provided. The vehicle steering control device. Disturbance type detection means for detecting the type of disturbance according to the generated frequency,
The disturbance type detection means includes
High-frequency disturbance detection means for detecting that the disturbance is a high-frequency disturbance comprising a frequency component higher than a predetermined frequency;
Including at least one of low-frequency disturbance detection means for detecting that the disturbance is a low-frequency disturbance including a frequency component lower than the predetermined frequency,
The viscosity compensation means calculates the compensation torque when the high-frequency disturbance is detected by the disturbance type detection means,
The said reaction force compensation means calculates the said compensation torque, when the said low frequency disturbance is detected by the said disturbance kind detection means, The compensation torque of any one of Claim 1-8 characterized by the above-mentioned. The vehicle steering control device.   10. The vehicle steering control device according to claim 9, wherein the high-frequency disturbance detection unit detects the high-frequency disturbance using a high-pass filter.   11. The vehicle steering control device according to claim 9, wherein the low-frequency disturbance detection unit detects the low-frequency disturbance using a low-pass filter.

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