Control method for yaw stability of electric vehicle driven by four-wheel hub motor

Abstract

A four-wheel hub motor driven electric vehicle yaw stability control method belongs to the technical field of control. The object of the present invention is to provide a four-wheel hub motor driven electric vehicle yaw stability control method that achieves better stability by tracking a desired centroid side drift angle and a desired yaw rate. The method of the invention obtains the reference values of the centroid side drift angle and the yaw rate under the ideal motion state of a vehicle through a two-degree-of-freedom reference model, designs a yaw moment optimization model prediction controller and converts an optimal additional yaw moment into four wheel hub motor additional torques to complete distribution. The yaw stability controller designed by the invention can effectively track the reference values of the centroid side drift angle and the yaw rate, and takes into consideration the factors of the tire lateral force saturation under the extreme working conditions, so that the prediction model is more accurate and at the same time a relatively small additional yaw moment is solved. In addition, the energy loss is reduced.

Description

technical field [0001] The invention belongs to the technical field of control. Background technique [0002] With the increasingly serious energy crisis and environmental pollution, electric vehicles have become an important research object in many countries in the world because of their advantages such as clean energy and low emissions. Nowadays, the automobile industry is developing rapidly, the number of automobiles is increasing, and the road traffic conditions are becoming more and more complicated. Improving the safety of automobiles has become a very important issue. Under extreme conditions, the safety state of the car is close to or reaches the physical limit, and the stability drops sharply, which may easily lead to major traffic accidents. The problem of vehicle safety under extreme working conditions is a common problem faced by the world, and it is the core driving force to promote the development of vehicle technology. The direct yaw moment of a centrally dr...

AI Technical Summary

Problems solved by technology

The existing control algorithm ignores the tire lateral force saturation under extreme conditions, and does not constrain the tire lateral force, resulting in a decline in the tracking ability of the car

[0005] 3. The existing electric vehicle yaw stability control method is calculating the additional yaw moment ΔM z When it is not constrained, the calculated additional torque acting on the automobile motor is relatively large, resulting in the consumption of a large amount of energy when the tire longitudinal force is used to generate the required additional yaw moment

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