JP4717104B2 - Vehicle steering control device - Google Patents

Description

  The present invention relates to a vehicle steering control device such as an electric power steering device mounted on a vehicle (such as an automobile), and in particular, detects that a disturbance such as a crosswind, a rut, or a cant (tilt) is applied. The present invention relates to a vehicle steering control device capable of suppressing the influence when a disturbance occurs.

  In general, when the vehicle is traveling straight, if a disturbance such as strong crosswind, hail, or cant is applied, the handle will be taken off by the disturbance torque, so the driver of the vehicle can continue to travel straight ahead. There are cases where corrective steering is performed or an operation for stabilizing vehicle behavior disturbed by a disturbance is performed. In such a situation, in order to reduce a driver's steering load, a technique for adding disturbance compensation torque by an electric motor of an electric power steering device has been proposed.

  When the above disturbance occurs, the influence of the disturbance appears in the steering shaft and the vehicle behavior. For example, state quantities such as steering angle, steering angular velocity, steering torque, and road surface reaction force torque are affected by disturbance in the steering shaft, and state quantities such as yaw rate, lateral acceleration, and sideslip angle are affected by disturbance. to be influenced.

The state quantities in the steering shaft and the vehicle behavior can be classified into two types, static state quantities and dynamic state quantities. The static state quantity is the amount of force that does not involve movement, and the dynamic state quantity is the amount of movement. That is, among the state quantities, the steering torque and the road reaction torque are static state quantities, and the steering angle, the steering angular velocity, the yaw rate, the lateral acceleration, and the skid angle are dynamic state quantities.
When a disturbance occurs, it is necessary to reduce the influence on both the static state quantity and the dynamic state quantity.

  As a conventional vehicle steering control device, for example, “steering off” caused by disturbance is detected from the steering angular velocity of the steering shaft, and the irregular behavior of the vehicle is detected from the yaw rate or lateral acceleration of the vehicle, and steering is performed. A technique for adding disturbance compensation torque so as to attenuate disturbance due to disturbance based on angular velocity and yaw rate or lateral acceleration is known (see, for example, Patent Document 1).

JP 2000-33879 A

  In the conventional vehicle steering control device, when a disturbance occurs, it is necessary to reduce the influence on the static state quantity and the dynamic state quantity. However, in the technique described in Patent Document 1, the steering angular velocity and the yaw rate are reduced. However, although a dynamic state quantity such as lateral acceleration is taken into consideration, a static state quantity such as steering torque is not taken into consideration, so that the load on the driver cannot be reduced sufficiently. there were.

  The present invention has been made to solve the above problems, and generates the optimum disturbance compensation torque by considering the influence of both the dynamic state quantity and the static state quantity due to the disturbance. An object of the present invention is to obtain a vehicle steering control device that can realize a driver's load reduction and a stable steering state.

The vehicle steering control device according to the present invention is configured to detect a steering torque detected by the driver to the steering shaft of the vehicle, a motor that generates at least an auxiliary torque corresponding to the steering torque, and a disturbance to the vehicle. A disturbance occurrence detecting means for detecting, and a disturbance compensator for determining a disturbance compensation torque command value to the motor when the disturbance occurrence detecting means detects occurrence of the disturbance, the disturbance compensator is generated on the steering shaft. A first parameter based on a static state quantity, and a second parameter based on a dynamic state quantity that occurs on the steering shaft or appears in the behavior of the vehicle , the first parameter and the second The disturbance compensation torque command value is determined by adding the parameter .

  According to the present invention, when a disturbance such as a kite, a crosswind, or a cant occurs, it is possible to determine a disturbance compensation torque that reduces the influence on both the dynamic state quantity and the static state quantity, It is possible to reduce the driver's steering load and to realize a stable steering state.

Embodiment 1 FIG.
Embodiment 1 of the present invention will be described below with reference to the accompanying drawings.
1 is a perspective view schematically showing an overall configuration of a vehicle steering control apparatus according to Embodiment 1 of the present invention.

  In FIG. 1, a vehicle steering control device mainly including a control unit (ECU) 8 is attached to a steering mechanism (steering mechanism) 10 of the vehicle. A control unit 8 for EPS (Electric Power Steering) is electrically combined with the steering mechanism 10.

  The steering mechanism 10 includes a steering handle (hereinafter simply referred to as “handle”) 1, a steering shaft 2, a steering gear box 3, a rack and pinion mechanism 6, and a tire 7.

  The vehicle steering control device includes a torque sensor 4 and an assist motor (hereinafter simply referred to as “motor”) 5 attached to the steering shaft 2, a handle angle sensor 9 attached to the handle 1, and control for controlling the motor 5. A unit 8 and a cable for connecting each element 4, 5, 9 to the control unit 8 are configured.

The vehicle steering control device naturally includes a power supply device (on-vehicle battery) that supplies power to each of the elements 4, 5, 9 and the control unit 8, but is omitted here because it is obvious.
Although not shown in FIG. 1, the motor 5 includes a known control circuit as will be described later.

The handle 1 is connected to the upper end of the steering shaft 2 and is steered by the driver of the vehicle. A steering torque Th by a driver is applied to the steering wheel 1, and this steering torque Th is transmitted to the steering shaft 2. The torque sensor 4 is coupled to the steering shaft 2 and generates a steering torque signal Th (s) (detection signal) corresponding to the steering torque Th.
The handle angle sensor 9 attached to the handle 1 detects the rotation angle of the handle 1 by the driver's steering as the handle angle θh, and outputs a handle angle signal θh (s).

The electric motor 5 is coupled to the steering shaft 2 via a reduction gear (not shown), and is driven under the control of the control unit 8 to supply an auxiliary torque Ts for assisting the steering torque Th to the steering shaft. Give to 2.
The steering gear box 3 is provided at the lower end of the steering shaft 2.
The combined torque obtained by adding the steering torque Th and the auxiliary torque Ts applied to the steering shaft 2 is multiplied several times through the steering gear box 3, and the tire 7 is operated through the rack and pinion mechanism 6.

Next, the overall operation of the vehicle steering control apparatus according to Embodiment 1 of the present invention shown in FIG. 1 will be described.
The control unit 8 includes a steering torque signal Th (s) from the torque sensor 4, a handle angle signal θh (s) from the handle angle sensor 9, and a motor drive current signal Im (s) (detection signal) from the motor 5. The control signal Im (t) corresponding to the drive target current is supplied to the motor 5 based on the arithmetic processing using the motor drive voltage signal Vm (s) (detection signal) as input information.

  1 detects the steering torque Th when the driver operates the steering wheel 1 as a steering torque signal Th (s) by the torque sensor 4, and the steering torque signal Th ( The main function is to generate an auxiliary torque Ts for assisting the steering torque Th according to s).

  That is, the control unit 8 controls the motor drive current signal Im (s) (the detected value of the drive current Im of the motor 5), the motor drive voltage signal Vm (s) (the detected value of the drive voltage Vm of the motor 5), and the steering. Based on the torque signal Th (s), a control signal Im (t) for generating the auxiliary torque Ts is calculated, and the control signal Im (t) is supplied to the motor 5.

Mechanically, the sum of the steering torque Th and the auxiliary torque Ts rotates the steering shaft 2 against the steering shaft reaction torque Tt applied to the steering shaft 2.
Further, since the inertia term of the motor 5 also acts when the handle 1 is rotated, the steering shaft reaction force torque Tt uses the inertia torque J · dw / dt of the motor 5 based on the motor angular velocity w and the inertia moment J, It is given by the following formula (1).

  Tt = Th + Ts−J · dw / dt (1)

  The auxiliary torque Ts by the motor 5 is given by the following equation (2) using the reduction gear ratio Gr of the reduction gear between the motor 5 and the steering shaft 2 and the torque constant Kt of the motor 5.

  Ts = Gr · Kt · Im (2)

  The steering shaft reaction force torque Tt is the sum of the actual road surface reaction force torque Ta and the friction torque Tfr in the steering mechanism 10, and the friction torque Tfm in the motor 5 and the friction torque Tfp in the steering mechanism 10 are And is given by the following equation (3).

Tt = Ta + Tfr
= Ta + (Gr · Tfm + Tfp) (3)

  In equation (3), the friction torque Tfp (= Tfr−Tfm · Gr) of the steering mechanism 10 is a value excluding the friction torque Tfm in the motor 5.

The control unit 8 calculates a target value for the drive current Im of the motor 5 and generates a control signal Im (t), so that the actual drive current Im of the motor 5 matches the control signal Im (t). Be controlled.
As a result, the motor 5 has a predetermined auxiliary value obtained by multiplying the value of the drive current Im by the torque constant Kt and the gear ratio Gr (the gear ratio between the motor 5 and the steering shaft 2) as in the above equation (2). Torque Ts is generated to assist the steering torque Th when the driver steers.

FIG. 2 is a block diagram showing a functional configuration of the control unit 8 and shows a control circuit in the motor 5 and various sensor means.
In FIG. 2, the control unit 8 includes a vehicle speed detector 11, a steering torque detector 12, a motor angular velocity detector 13, a motor angular acceleration detector 14, a handle angle detector 15, and a steering torque change rate calculating means. 16, a steering wheel angle change rate calculating means 17, an auxiliary torque determination block 18, a motor current determiner 19, a motor current comparator 20 comprising a subtractor, a motor driver 21, a motor current detector 22, Disturbance generation detecting means 23 is provided.

The vehicle speed detector 11 receives the vehicle speed V of the vehicle and outputs a vehicle speed signal V (s).
The steering torque detector 12 including the torque sensor 4 (FIG. 1) receives the steering torque Th and outputs a steering torque signal Th (s).
The motor angular velocity detector 13 cooperating with the control circuit in the motor 5 receives the motor angular velocity w of the motor 5 and outputs a motor angular velocity signal w (s).

The motor angular acceleration detector 14 differentiates the motor angular velocity signal w (s) and outputs a motor angular acceleration signal Am (s).
The handle angle detector 15 including the handle angle sensor 9 (FIG. 1) receives the handle angle θh and outputs a handle angle signal θh (s).
The steering torque change rate calculating means 16 receives the steering torque signal Th (s) and outputs a steering torque change rate signal dTh (s).
The steering wheel angular velocity calculation means 17 differentiates the steering wheel angle signal θh (s) and outputs a steering wheel angular velocity signal dθh (s).

  The disturbance occurrence detecting means 23 receives the steering torque change rate signal dTh (s) and the steering wheel angular velocity signal dθh (s), detects the disturbance occurrence, and outputs a disturbance torque detection signal D_flag (s). The specific configuration of the disturbance occurrence detection means 23 can be realized by a known technique (for example, see Japanese Patent Application Laid-Open No. 2002-264832).

The auxiliary torque determination block 18 includes a vehicle speed signal V (s), a steering torque signal Th (s), a motor angular speed signal w (s), a motor acceleration signal Am (s), and a disturbance torque detection signal D_flag (s). In response, an auxiliary torque signal Ts (s) corresponding to the auxiliary torque Ts generated by the motor 5 is generated.
The motor current determiner 19 receives the auxiliary torque signal Ts (s) and outputs a target current value Ir (s) for the drive current Im of the motor 5 for actually generating the auxiliary torque Ts.

The motor current comparator 20, the motor driver 21 and the motor current detector 22 are provided for driving the motor 5.
The motor current detector 22 outputs a motor drive current signal Im (s) corresponding to the actual drive current Im of the motor 5.

The motor current comparator 20 compares the current target value Ir (s) with the motor drive current signal Im (s) and outputs a current deviation (Ir (s) −Im (s)) between them.
The motor driver 21 drives the motor 5 so that the current deviation between the current target value Ir (s) and the drive current signal Im (s) is “0”.

FIG. 3 is a block diagram showing a functional configuration of the auxiliary torque determination block 18 in FIG.
In FIG. 3, the auxiliary torque determination block 18 includes an assist map compensator 30, an inertia compensator 31, a viscosity compensator 32, a disturbance compensator 33, and an adder 34.
The detailed function of the disturbance compensator 33 in the auxiliary torque determination block 18 corresponds to the main matter of the present invention and will be described later.

The assist map compensator 30 receives the vehicle speed signal V (s) and the steering torque signal Th (s) and outputs an assist map compensation torque signal map (s).
The inertia compensator 31 receives the vehicle speed signal V (s) and the motor angular acceleration signal Am (s) and outputs an inertia compensation torque signal iner (s).
The viscosity compensator 32 receives the vehicle speed signal V (s) and the motor angular speed signal w (s), and outputs a viscosity compensation torque signal damp (s).
The disturbance compensator 33 receives the steering torque signal Th (s), the steering wheel angular velocity signal dθh (s), and the disturbance torque detection signal D_flag (s), and outputs a disturbance compensation torque signal dist (s).

1 to 3, the compensator function of the auxiliary torque determination block 18 is limited to the assist map compensator 30, the inertia compensator 31, the viscosity compensator 32, and the disturbance compensator 33. Various other compensator functions may be provided.
Similarly, as input signals to the auxiliary torque determination block 18, a vehicle speed signal V (s), a steering torque signal Th (s), a motor angular acceleration signal Am (s), a motor angular speed signal w (s), Although limited to the steering wheel angular velocity signal dθh (s) and the disturbance torque detection signal D_flag (s), various other input signals may be used.

Next, the necessity of the disturbance compensator 33 in the auxiliary torque determination block 18 will be described in detail with reference to FIGS. 1 to 3 and the timing chart of FIG. 4 (when the disturbance compensator 33 is not provided).
FIG. 4 shows the correlation between the dynamic state quantity (steering wheel angle θh, steering wheel angular speed dθh) and the static state quantity (steering torque Th) in the steering shaft 2 when a disturbance due to wrinkles occurs. Shown in change.

  In FIG. 4, on the left side (a), each state quantity when the driver holds the steering wheel 1 weakly (steering) (for example, a one-hand steering state or a state where a hand is attached to the steering wheel 1) is shown. On the right side (b), each state quantity when the driver holds the steering wheel 1 strongly (steering) is shown.

In both cases shown in FIGS. 4A and 4B, “steering off” occurs due to disturbance torque, but there is a difference in the tendency of the occurrence.
That is, as can be seen from the broken line frame in FIG. 4A, when a disturbance occurs while the driver is holding the handle 1 weakly, the handle 1 turns many times, so that the dynamic state quantity is increased. The effect of. On the other hand, as shown by the broken line frame in FIG. 4B, when the driver holds the handle 1 strongly, the handle 1 is difficult to turn. The effect on the state quantity becomes large.

As shown in FIGS. 4A and 4B, the static state quantity and the dynamic state quantity change depending on the driver's steering condition. It is necessary to appropriately suppress both the state quantity.
According to the first embodiment of the present invention, the disturbance compensation torque signal dist (s) is determined based on the static state quantity and the dynamic state quantity, thereby reducing the influence on both state quantities. be able to.

Next, a specific operation of the disturbance compensator 33, which is a feature of the present invention, will be described with reference to FIG.
FIG. 5 is a block diagram showing a specific functional configuration of the disturbance compensator 33 (FIG. 3) in the auxiliary torque determination block 18.
In FIG. 5, the disturbance compensator 33 includes a multiplier 40 having a first gain G1, a multiplier 41 having a second gain G2, and an adder 42 for adding output parameter values of the multipliers 40 and 41. The upper / lower limit setting means 43 for setting the upper and lower limits to the output value of the adder 42 and the disturbance compensation torque determination means 44 are provided.

Hereinafter, a series of operations of each block in the disturbance compensator 33 shown in FIG. 5 will be described with reference to the flowchart of FIG. 6.
In FIG. 6, the processing of steps S1 to S9 is included from the start (START) to the end (END) of the operation routine.

  Further, as shown in FIG. 5, step S1 corresponds to the processing of the multiplier 40, step S2 corresponds to the processing of the multiplier 41, and step S3 corresponds to the processing of the adder 42. Further, step S4 corresponds to the processing of the upper / lower limit setting means 43, and steps S5 to S8 correspond to the processing of the disturbance compensation torque determination means 44.

First, the disturbance compensator 33 reads the steering torque signal Th (s) into the memory, and the multiplier 40 multiplies the steering torque signal Th (s) by the first gain G1 to obtain the first parameter Pa1 (s ) Is obtained (step S1).
Further, the steering wheel angular velocity signal dθh (s) is read into the memory, and the multiplier 40 multiplies the steering wheel angular velocity signal dθh (s) by the second gain G2 to obtain the second parameter Pa2 (s) (step S2). ).

Next, the adder 42 adds the first parameter Pa1 (s) and the second parameter Pa2 (s) to obtain an addition parameter value Pa_sum (s) (step S3).
At this time, a dead zone may be set for each of the first and second parameters Pa1 (s) and Pa2 (s).

Subsequently, in the upper / lower limit value setting means 43, when the addition parameter value Pa_sum (s) exceeds the preset upper / lower limit value, the upper / lower limit clip process is performed (step S4).
At this time, the preset upper and lower limit values may be variably set according to the vehicle speed signal V (s). Further, upper and lower limit values may be set for each of the first and second parameters Pa1 (s) and Pa2 (s).

  Next, the disturbance torque detection signal D_flag (s) is read into the memory (step S5), and the disturbance compensation torque determining means 44 is in a disturbance occurrence state based on the presence or absence of the disturbance torque detection signal D_flag (s). It is determined whether or not (step S6).

If it is determined in step S6 that a disturbance has occurred (that is, Yes), the disturbance compensation torque signal dist (s) is set as the limit compensation value Pre_dist (s) that is the calculation result of step S4 (step S7). Proceed to step S9.
On the other hand, if it is determined in step S6 that the disturbance is not generated (that is, No), the disturbance compensation torque signal dist (s) is set to “0” (step S8), and the process proceeds to step S9.

Finally, the disturbance compensation torque determining means 44 outputs a disturbance compensation torque signal dist (s) (step S9), and the processing routine of FIG.
Hereinafter, the disturbance compensation torque signal dist (s) is input to the adder 34 (FIG. 3) in the auxiliary torque determination block 18, and the assist map compensation torque signal map (s), the inertia compensation torque signal inner (s), and the viscosity. It is added together with the compensation torque signal damp (s) and output from the auxiliary torque determination block 18 as the auxiliary torque signal Ts (s).

  As described above, the disturbance compensation torque signal dist (s) is determined based on the steering torque signal Th (s) that is a static state quantity and the steering wheel angular velocity signal dθh (s) that is a dynamic state quantity. As a result, both the influence on the static state quantity and the influence on the dynamic state quantity can be appropriately suppressed.

Here, the effects when the first embodiment of the present invention is applied will be described with reference to the timing chart of FIG. 7 (when the disturbance compensator 33 is provided).
In FIG. 7, as in FIG. 4 described above, the dynamic state quantities (steering wheel angle θh, steering wheel angular speed dθh) and static state quantities (steering torque) in the case where a disturbance due to wrinkles or the like occurs. The time change with Th) is shown according to the steering condition.

In FIG. 7, the solid behavior curve indicates the behavior when the disturbance compensator 33 is provided, and the broken behavior curve indicates the behavior when the disturbance compensator 33 is not provided (FIG. 4). The difference due to the presence or absence of is shown in comparison.
As described above, the disturbance compensator 33 determines the disturbance compensation torque signal dist (s) in consideration of both the static state quantity and the dynamic state quantity. Therefore, as shown in FIG. It is possible to appropriately suppress the influence on the static state quantity and the dynamic state quantity (see the white arrow) regardless of the steering state of the person.

  As described above, the vehicle steering control apparatus according to the first embodiment of the present invention is the steering torque detecting means (torque sensor 4, steering torque detector) for detecting the steering torque Th to the steering shaft 2 of the vehicle by the driver. 12), a motor 5 that generates an auxiliary torque Ts corresponding to at least the steering torque Th, a disturbance generation detection unit 23 that detects the occurrence of a disturbance to the vehicle, and a disturbance generation detection unit 23 that detects the occurrence of a disturbance. And a disturbance compensator 33 for determining a disturbance compensation torque signal dist (s) (disturbance compensation torque command value) to the motor 5.

  The disturbance compensator 33 is a first parameter Pa1 (s) based on a static state quantity generated on the steering shaft 2 and a dynamic state quantity generated on the steering shaft 2 or appearing in the behavior of the vehicle. The disturbance compensation torque signal dist (s) is determined using the second parameter Pa2 (s) based thereon.

  Specifically, the disturbance compensator 33 has a first gain G1 and a second gain set in advance. The first parameter Pa1 (s) is a value obtained by multiplying the static state quantity by the first gain G1 so that the influence of the disturbance on the static state quantity is reduced, and the second parameter Pa2 ( s) is a value obtained by multiplying the dynamic state quantity by the second gain G2 so that the influence of the disturbance on the dynamic state quantity is reduced, and the disturbance compensator 33 uses the first parameter Pa1 ( The disturbance compensation torque signal dist (s) is determined by adding s) and the second parameter Pa2 (s).

  As a result, when disturbances such as dredging, crosswinds, and cantes occur, it is optimal to reduce the influence of disturbances by considering the effects of both disturbances on dynamic and static state quantities. The disturbance compensation torque signal dist (s) can be generated to realize both the driver's load reduction and a stable steering state.

  The static state quantity includes the steering torque Th or the road surface reaction torque Ta received by the vehicle wheel 7 from the road surface. The dynamic state quantity includes the steering wheel angle θh and the steering wheel angular velocity dθh of the steering shaft 2, the vehicle yaw rate, It includes at least one of lateral acceleration and side slip angle.

The disturbance compensator 33 includes an upper / lower limit setting unit 43, and corrects the auxiliary torque Ts within the normal operation range by setting an upper limit value and a lower limit value in the disturbance compensation torque signal dist (s).
Furthermore, if necessary, the disturbance compensator 33 sets a dead zone for each of the first and second parameters Pa1 (s) and Pa2 (s) to avoid useless hunting control.

  In the first embodiment, the steering torque signal Th (s) is used to determine the first parameter Pa1 (s). However, the assist map compensation torque signal map determined based on the steering torque Th is used. As in (s), the use of a state quantity corresponding to the steering torque Th and a motor drive current signal Im (s) based on the steering torque Th are also synonymous.

  In order to determine the second parameter Pa2 (s), the steering wheel angular velocity signal dθh (s) is used, but the motor angular velocity signal w (s) having a 1 / Gr-fold relationship with respect to the steering wheel angular velocity dθh is used. Use is synonymous. Further, instead of the steering wheel angular velocity dθh, the steering wheel angle θh may be simply used.

Further, in order to determine the first parameter Pa1 (s), the road surface reaction force torque Ta, which is a static state quantity generated in the steering shaft 2, may be used, and the steering torque Th and the road surface reaction force torque Ta may be determined. Both may be used.
Thus, by using the road surface reaction force torque Ta, it becomes possible to detect the disturbance torque generated from the road surface with high accuracy, and to further effectively suppress the influence of the disturbance.

  The road surface reaction force torque Ta can be obtained by attaching a detector (such as a load cell) to the tire 7. Alternatively, as is publicly known (for example, Japanese Patent Application Laid-Open No. 2003-312521), the road surface reaction force torque Ta can be calculated by a microcomputer that constitutes the control unit 8 of the vehicle steering control device.

In addition, in order to determine the second parameter Pa2 (s), a dynamic state quantity (any one of yaw rate, lateral acceleration, and sideslip angle) appearing in the vehicle behavior is used, or appears in the steering shaft 2 and the vehicle. A plurality of dynamic state quantities may be used.
As described above, by determining the second parameter Pa2 (s) based on the dynamic state quantity representing the vehicle behavior, the influence on the vehicle behavior due to the disturbance can be effectively suppressed. As a result, it is possible to improve both the steering feeling obtained by the first parameter Pa1 (s) and the stable vehicle behavior obtained by the second parameter Pa2 (s).
The yaw rate can be detected by attaching a yaw rate sensor, the lateral acceleration is a lateral acceleration sensor, and the skid angle can be detected.

Further, the disturbance compensator 33 does not use the vehicle speed signal V (s) in determining the disturbance compensation torque signal dist (s), but corrects the disturbance compensation torque signal dist (s) according to the vehicle speed V of the vehicle. May be.
That is, the disturbance compensation torque signal dist (s) may be corrected by a preset map of the vehicle speed signal V (s), and the first and second gains G1 and G2 are set according to the vehicle speed signal V (s). May be corrected.

1 is a perspective view schematically showing an overall configuration of a vehicle steering control device according to Embodiment 1 of the present invention. FIG. FIG. 2 is a block diagram specifically illustrating a functional configuration of a control unit in FIG. 1. FIG. 3 is a block diagram specifically showing a functional configuration of an auxiliary torque determination block in FIG. 2. It is a timing chart for demonstrating the handle | steering_wheel taken state by disturbance (轍). FIG. 4 is a block diagram specifically showing a functional configuration of a disturbance compensator in FIG. 3. It is a flowchart which shows a series of operation | movement of the disturbance compensator by Embodiment 1 of this invention. It is a timing chart for demonstrating the effect of the disturbance compensator by Embodiment 1 of this invention.

Explanation of symbols

  1 steering wheel, 2 steering shaft, 4 torque sensor, 5 motor, 7 tires, 8 control unit (ECU), 9 steering wheel angle sensor, 10 steering mechanism, 11 vehicle speed detector, 12 steering torque detector, 13 motor angular velocity detector, DESCRIPTION OF SYMBOLS 14 Motor angular acceleration detector, 15 Steering wheel angle detector, 16 Steering torque change rate calculating means, 17 Steering wheel angular velocity calculating means, 18 Auxiliary torque determination block, 19 Motor current determiner, 20 Motor current comparator (subtractor), 21 Motor driver, 22 Motor current detector, 23 Disturbance generation detection means, 30 Assist map compensator, 31 Inertia compensator, 32 Viscosity compensator, 33 Disturbance compensator, 40, 41 Multiplier, 42 Adder, 43 Upper and lower limits Setting means, 44 Disturbance compensation torque determining means, dist (s) Disturbance compensation torque No. (disturbance compensation torque command value), G1 first gain, G2 second gain, Pa1 (s) first parameter, Pa2 (s) a second parameter.

Claims (5)

Steering torque detection means for detecting steering torque to the steering shaft of the vehicle by the driver;
A motor that generates at least auxiliary torque according to the steering torque;
Disturbance occurrence detecting means for detecting the occurrence of disturbance to the vehicle;
A disturbance compensator for determining a disturbance compensation torque command value to the motor when the disturbance occurrence detecting means detects the occurrence of disturbance;
The disturbance compensator is:
A first parameter based on a static state quantity generated in the steering shaft;
Or generated in the steering shaft, or a second parameter based on the dynamic state amount appearing on the behavior of the vehicle,
The vehicle steering control apparatus, wherein the disturbance compensation torque command value is determined by adding the first parameter and the second parameter . The static state quantity includes the steering torque or a road surface reaction torque received by a wheel of the vehicle from a road surface,
2. The vehicle steering according to claim 1 , wherein the dynamic state quantity includes at least one of a steering wheel angle and a steering wheel angular velocity of the steering shaft, a yaw rate, a lateral acceleration, and a skid angle of the vehicle. Control device. The disturbance compensator vehicular steering control apparatus according to claim 1 or claim 2, characterized in that to correct the disturbance compensation torque command value according to the vehicle speed of the vehicle. 4. The vehicle steering control device according to claim 1 , wherein the disturbance compensator sets an upper limit value and a lower limit value for the disturbance compensation torque command value. 5. 5. The vehicle steering control according to claim 1 , wherein the disturbance compensator sets a dead zone for each of the first parameter and the second parameter. 6. apparatus.

Images