Control method of electro-hydraulic type power-assisted steering system

Abstract

The invention discloses a control method of an electro-hydraulic type power-assisted steering system. The system comprises a motor, an energy accumulator, a hydraulic pump, an oil storage groove, a steering valve, a steering power-assisted cylinder and a control unit and the like, wherein a look-up table for data of the threshold value range of oil pressure of the energy accumulator is preset in the storage of the controller, and the data the threshold value range of oil pressure of the energy accumulator corresponds to the size of the needed assisting steering power calculated according to parameters such as the speed and the steering torque and the like of a vehicle; when the steering occurs, the control unit obtains the upper and lower limit threshold value of the oil pressure of the needed energy accumulator by acquiring signals such as the speed and the steering torque and the like of the current vehicle and inquiring in the look-up table. In the control method, the corresponding size of the assisting power can be provided according to the driving condition and the current assisting power need of the vehicle, the controllability of the vehicle in steering is effectively improved and the energy consumption is saved.

Description

technical field [0001] The invention relates to the technical field of automobiles, in particular to a control method of an electrohydraulic power steering system. Background technique [0002] With the rapid development of modern automobile technology, people's requirements for automobile steering performance are increasing day by day. As the main device to control the driving route and direction of the car, the car steering system directly affects the steering characteristics of the car, the driver's operating feel and driving safety. [0003] The traditional hydraulic power steering system is directly driven by the engine to the hydraulic pump. Its power-assist characteristics are determined by the steering servo valve and the oil supply of the oil pump. The flow of oil output by the oil pump is not controlled by the outside world, and the power-assist characteristics are inconsistent with the actual needs of the car. The handling performance is poor, and the vehicle can...

AI Technical Summary

Problems solved by technology

[0003] The traditional hydraulic power steering system is directly driven by the engine to the hydraulic pump. Its power-assist characteristics are determined by the steering servo valve and the oil supply of the oil pump. The flow of oil output by the oil pump is not controlled by the outside world, and the power-assist characteristics are inconsistent with the actual needs of the car. The control performance is poor, and the vehicle cannot be stopped at idling speed, that is, the engine cannot stop working when the vehicle is idling, and the engine is always working, and the energy saving effect is poor

However, the electric power steering system is complex in structure and expensive, and requires a large motor power when used in electric buses

The existing electro-hydraulic power steering system control method needs to continuously adjust the voltage, current and operating frequency of the motor according to the different steering states of the car. The control unit has complex calculations and a large amount of calculations. not ideal

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