CN100408407C

CN100408407C - Restoring and controlling method of power steering system

Info

Publication number: CN100408407C
Application number: CNB2004100857393A
Authority: CN
Inventors: 金成柱
Original assignee: Mando Corp
Current assignee: Mando China Holdings Ltd; HL Mando Corp
Priority date: 2004-10-11
Filing date: 2004-10-11
Publication date: 2008-08-06
Anticipated expiration: 2024-10-11
Also published as: CN1760073A

Abstract

The present invention relates to a restoring and controlling method in a power steering system. The method can enhance the restoring and controlling functions of a restoring period after steering. In the method, a steering angle and the speed of the steering angle are used for distinguishing a restoring state by judging whether the speed of the steering angle is larger than a preset value or not, and the restoring control is only executed in the corresponding restoring state. The restoring and controlling method of the present invention comprises the steps: firstly, setting the restoring gain and a restoring mode; secondly, obtaining restoring current; thirdly, judging whether the speed of the steering angle is larger than the preset value or not; fourthly, obtaining the drive current of a motor, and controlling the operation of the motor according to the obtained drive current of the motor to realize the restoring and controlling functions.

Description

Recovery control method in the power steering system

Technical field

The present invention relates to the recovery control method in the power steering system, and relate in particular to a kind of like this recovery control method in the power steering system, this method can strengthen restoring control function between the convalescence after turning to, it utilizes steering angle and deflection angle speed, return to form by judging that whether deflection angle speed distinguished greater than a predetermined value, and only recover control according to cooresponding returning to form.

Background technology

Generally speaking, electronic control component (being called " ECU " hereinafter) is housed all on power actuated vehicle, this control element receives detected electric signal from various input pickups, and handles various equipments at mouth output electric control signal.

Simultaneously, also developed a kind of EPS system, the such ECU of this system's utilization, reduced the propulsive effort of driver's bearing circle, thereby realized steering operation quickly and easily according to the speed of vehicle.As shown in fig. 1, comprise a sensor element 1 in this EPS system, such as a speed sensor that detects car speed, detect the motor position sensor (if or steering angle sensor-this vehicle has steering angle sensor) of the relative steering angle of electrical motor, detect torque sensor of driver's steering wheel torque or the like, an ECU 2, this element receives detected signal from sensor element 1, and export various motor control signals and operation signal, so that reduce the propulsive effort of driver's bearing circle, also comprise a motor control and driver element 3, this element basis is from the motor control signal of ECU 2 and the work at operation signal control motor, and turning to auxiliary force to operate steering hardware by one, this turns to auxiliary force is that running according to electrical motor generates power by one and causes.

So except common hydraulic power steering system, also comprise an accessory device in the EPS system of structure,, thereby increased friction such as electrical motor or reducing gear.Therefore, during turning to, understand the characteristic that occurs such as friction sense or bad stability.

Therefore, steering torque will be illustrated with respect to the figure line that concerns that turns to the input angle, and in the figure, hysteresis phenomenon is more serious than other hydraulic power steering vehicles.In original technology, restoring control function is used to compensate this defective.

Especially, finding that back track to the speed of revolutions of dish or be detained angle when not being held, will carry out and recover control.That is to say,, will utilize an absolute steering angle signal to produce an auxiliary current, make bearing circle towards a midway location, thereby make bearing circle turn to back homing easily by this electric current if the driver decontrols bearing circle.

Yet in the recovery control method of original technology, what return to form distinguishes by judging whether the driver decontrols bearing circle and finish, when the signal of torque sensor just thinks that the driver has decontroled bearing circle during less than a predetermined value.Therefore, if a problem will appear in the slow release direction dish of driver rather than decontrol bearing circle fully, promptly can not apply and recover control completely, this is owing to there is a less torque capacity on the bearing circle.

In other words, as shown in Figure 2, be provided with one and a recovery pattern (S2) corresponding to steering angle be set, multiply each other and obtain a restoring current (S3) by recovering gain and recovery pattern then corresponding to the recovery of car speed gain (S1).

Subsequently, judge whether steering torque is positioned at dead band (dead band is exactly the scope that moment of torsion can not fall into) (S4).

If the judged result of step S4 shows, because the driver has decontroled bearing circle, and cause bearing circle not to be in a straight mobile status, and steering torque is positioned at the dead band, and the restoring current that obtains among auxiliary current and the step S3 will be added to obtain a motor drive current (S5) so.Described auxiliary current obtains in conjunction with torque sensor signal and car speed information calculations.At last, the running that comes the control motor according to the motor drive current that obtains among the step S5, thus realize restoring control function.

Yet, in above-mentioned recovery control method, return to form and discern according to steering torque, just as in step S4, could carry out then and recover control.Subsequently, if the driver during Vehicular turn with bearing circle to the left and right direction rotate slightly, will occur immediately returning to form and steering state between frequent switching.Owing to this reason, recover control logic and will produce discontinuous motor drive current, thereby cause that the driver feels to turn to the jiggly problem of sense.

Summary of the invention

In design of the present invention, the problems of the prior art have been considered, therefore a target of the present invention will provide a kind of recovery control method exactly in the EPS system, the restoring control function that this method can obtain to strengthen, thereby obtain the more level and smooth sense that turns between the convalescence after turning to, this method is utilized steering angle and deflection angle speed to distinguish and is returned to form, under the condition of deflection angle speed, distinguish and return to form and carry out and recover control greater than a predetermined value, when being in alternating state, deflection angle speed do not carry out described recovery control, this situation is held Shi Caihui at bearing circle and is occurred, and just carries out described control during greater than certain predetermined value when the resume speed of bearing circle.

In order to realize above-mentioned target, according to the invention provides a kind of method of controlling recovered in power steering system, this method comprises: be provided with corresponding to the recovery gain of car speed in an ECU of EPS system and first step corresponding to the recovery pattern of steering angle is set; Thereby multiply each other by the recovery gain that will be provided with in the first step and recovery pattern and to obtain second step of a restoring current; Judge that the locational deflection angle speed of right-hand rotation Vehicular turn is whether greater than conter clockwise (CCW) direction lower limit or judge that deflection angle speed on the left turning vehicle steering position is whether greater than the third step of cw (CW) direction lower limit; And the 4th step, promptly show that the locational deflection angle speed of right-hand rotation Vehicular turn is greater than the deflection angle speed on anticlockwise direction lower limit or the left turning vehicle steering position during greater than the clockwise direction lower limit when the judged result in the third step, obtain a motor drive current in the Calais mutually by the restoring current that will obtain in an auxiliary current and second step, and according to the motor drive current control motor running that obtains, thereby realize restoring control function.

Description of drawings

According to the explanation of hereinafter with reference to accompanying drawing the specific embodiment being carried out, other targets of the present invention and other aspect contents will become apparent, in described accompanying drawing:

Fig. 1 shows the structured flowchart of traditional E PS system;

Fig. 2 shows a width of cloth diagram of circuit, and this figure has showed the recovery control method of prior art in the EPS system; And

Fig. 3 shows a width of cloth diagram of circuit, and this figure has showed recovery control method according to the invention in the EPS system.

The specific embodiment

Illustrate in greater detail the recovery control method in the EPS of the present invention system below with reference to accompanying drawings.

As shown in fig. 1, comprise a sensor unit 1 in the EPS system, comprising a vehicle speed sensor, a motor position sensor, a torque sensor etc., also comprise an ECU 2 and motor control and driver element 3 in the system.

Hereinafter, with reference to Fig. 3 the recovery control method of carrying out according to the invention is described in the EPS system that so makes up.

At first, the ECU 2 of EPS system is provided with a recovery gain (S11) corresponding to car speed, described car speed is to detect by the vehicle speed sensor in the sensor unit 1, recovery pattern (S12) corresponding to steering angle also will be set, and described steering angle is to detect by the motor position sensor in the sensor unit 1.

Then, recovery gain that will be provided with in step S11 and the recovery pattern that is provided with in step S12 multiply each other, so that obtain a restoring current (S13).

Then, judge steering angle-promptly by the detected steering position of the motor position sensor in the sensor unit 1 (or steering angle sensor)-whether be in the position that vehicle is turned right, and deflection angle speed is whether greater than the lower limit (S14) of conter clockwise (-) direction.It seems from the result who judges, if not steering position be vehicle when turning right residing position and deflection angle speed greater than the lower limit of conter clockwise (-) direction, will judge that so whether by the detected steering position of the motor position sensor in the sensor unit 1 be vehicle residing position when turning left, and deflection angle speed is whether greater than the lower limit (S15) of cw (+) direction.

In other words, judge that whether deflection angle speed is greater than certain reference steering angle speed by comparing the absolute value of deflection angle speed and conter clockwise (-) direction rotating speed lower limit and cw (+) direction rotating speed lower limit.Do like this is in order only just to recover control during greater than predetermined value in the resume speed of bearing circle.

Afterwards, result as step S14 and S15, if residing position and deflection angle speed were greater than the anti-clockwise lower limit when steering position was the vehicle right-hand rotation, perhaps steering position be vehicle residing position and deflection angle speed are greater than clockwise lower limit when turning left, ECU 2 will obtain a motor drive current (S16) in the Calais mutually by the restoring current that will obtain among auxiliary current and the step S13 so.At last, according to the running of starting the drive current control motor that obtains among the step S16, thereby realize restoring control function.

From above as seen, in the present invention, the driver felt turns to sense to recover control and strengthen by carrying out, and the executive mode of described recovery control is to utilize steering angle and deflection angle speed as applying the condition of recovering control and determining one to return to form in deflection angle speed during greater than certain predetermined value in the sub-divided condition.

As mentioned above, the present invention can realize the restoring control function that strengthens, thereby obtain the more level and smooth sense that turns between the convalescence after turning to, this method is utilized steering angle and deflection angle speed to distinguish and is returned to form, under the condition of deflection angle speed, distinguish and return to form and carry out and recover control greater than a predetermined value, when deflection angle speed is in alternating state, do not carry out described recovery control (this situation is held Shi Caihui at bearing circle and occurred), and just carry out described control during greater than certain predetermined value when the resume speed of bearing circle.

In other words, when having only resume speed when bearing circle, just carry out and recover control greater than certain predetermined value.Therefore, turning to and keeping under the situation of steering angle, the driver can be improved turns to sense.

Claims

1. one kind is recovered the method controlled in power steering system, and this method comprises:

First step is provided with the recovery gain corresponding to car speed in an ECU of EPS system, and the recovery pattern corresponding to steering angle is set;

Second step obtains a restoring current thereby multiply each other by the recovery gain that will be provided with in the first step and recovery pattern;

Third step, after having carried out second step, judge steering angle whether be the vehicle steering position of turning right and deflection angle speed whether greater than lower limit set value of anti-clockwise, or judge that whether steering angle is whether the steering position of vehicle left-hand rotation and deflection angle speed are greater than a clockwise lower limit set value; And

The 4th step, when the judged result in the third step shows that the locational deflection angle speed of right-hand rotation Vehicular turn is greater than the deflection angle speed on anticlockwise direction lower limit set value or the left turning vehicle steering position during greater than the clockwise direction lower limit set value, obtain a motor drive current in the Calais mutually by the restoring current that will obtain in an auxiliary current and second step, and come the control motor running, thereby realize restoring control function according to the motor drive current that obtains.