Robust Control of Electro-Hydraulic Coupling Power Steering System for Intelligent Commercial Vehicle with Varying Vehicle Speed

For the problems of inaccurate parameters and steering resistance disturbance in electro-hydraulic coupled power steering (EHCPS) system of intelligent commercial vehicles, we designed a dual-loop steering system corner controller. In this paper, firstly, we analyzed the complex uncertain parameters of the EHCPS system and then simplified it to the two-degree-of-freedom control model. Secondly, we analyzed the dynamic perturbations caused by vehicle speed changes and designed a compensating loop controller to calculate the corresponding steering wheel angle. Then, we linearize the steering resistance and the hydraulic power assist and designed the closed-loop robust controller for the main loop. Finally, we simulate the front wheel angle following of the steering of intelligent commercial vehicles under different speed conditions, and the results prove that the angle following under this controller has higher accuracy and have good robustness.