Method for controlling power-assisted motor of electrical power-assisted steering system under intervention of active steering

Abstract

The invention discloses a method for controlling a power-assisted motor of an electrical power-assisted steering system under the intervention of active steering, and belongs to the field of the control of power-assisted motors of electrical power-assisted steering systems having the active steering function. The method comprises the following steps of: calculating a required feedforward power-assisted amending control current signal deta Ia by utilizing a feedforward power-assisted amending control module (7) according to an additional intersection angle theta ac and a feedforward transfer function G deta I(s), performing linear superposition of the amending control current signal deta Ia and the conventional power-assisted control current signal Ia to obtain a power-assisted motor totalcontrol current signal for controlling the power-assisted motor to exert power-assisted moment Ta, wherein the power-assisted moment Ta and steering wheel torque Td exerted by drivers overcome steering resisting moment TR commonly, and driving a wheel to complete steering by a steering transmission mechanism (10). By the method, the problem that the control moment of a steering wheel is changed suddenly with the intervention of the active steering additional intersection angle under high-speed running is solved, the steering road feel of the steering system under the intervention of the active steering is improved, and the requirement for safe driving during the high-speed running is met.

Description

technical field [0001] The invention relates to a method for controlling a booster motor of an electric power steering system under the intervention of an additional rotation angle of active steering, and belongs to the field of control of a booster motor of an electric power steering system with integrated active steering functions. Background technique [0002] At present, the electric power steering system integrated with the active steering function has become the future development direction of the electric power steering system. Active steering essentially controls the angular displacement transfer characteristics of the steering system by imposing an additional rotation angle θ ac Change the angular displacement transmission characteristics of the steering system, realize variable transmission ratio control and active steering intervention control, and give full play to the role of the steering system in improving the stability of the vehicle. [0003] According to N...

AI Technical Summary

Problems solved by technology

However, the top speed of existing cars can reach more than 160Km / h, which means that when the speed range of the booster is exceeded, the booster gain k of the booster motor a (u) is zero. If the active steering applies an additional rotation angle at this time, this method cannot correct the sudden change in the steering wheel holding torque, which will lead to the deterioration of the handling performance of the steering system and cannot meet the needs of safe driving when the car is running at high speed.

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