Abstract:Most of the steering gear electro-hydraulic servo force control systems have the extraneous force problem. The dual electro-hydraulic servo valve parallel control, which is of the servo valve with high response and large flow and parallel control method with p-qv servo valve, is used to solve the above puzzle . Aiming at the nonlinear and time-varying characteristics of system, the control method combining fuzzy control and iterative learning control are used, i.e., one controller uses the fuzzy iterative learning control method, and the other uses the PI-iterative control method. The theoretical analysis and simulation results indicate that the double valve parallel control scheme has better ability to inhibit redundant force during the start and stop process of steering engine and can improve the loading performance and non-linear and time variable charact eristics of system.