Research On The Electric Load Test System Of The Steering Gear

The electric loading system of the steering gear is a simulation device that simulates the load on the rudder during the flight in the laboratory conditions.It is characterized by fast response,low cost,easy to use,etc.,and also need to meet the anti-interference ability,high precision loading requirements.However,the existence of excess torque and various nonlinear factors in the loading system will seriously affect the dynamic performance and loading accuracy of the system.Therefore,it is the key research content of the electric loading system to suppress the excess torque and improve the dynamic performance of the system.First of all,according to the working principle of the loading system,the paper establishes the mathematical model of the system by the mechanism modeling method,and analyzes loading performance and excess torque of the system.In this paper,the loading performance is analyzed from the aspects of mechanical resonant frequency and stability of the system.Advance correction and differential PI control are proposed for the problem that the stability can not meet the requirements of the system.The simulation results show that the static characteristics of the system are improved after correction;through the analysis of excess torque,the feedforward compensation method based on structural invariance is used to suppress it,mainly by observing the steering command control signal and the DC motor speed compensation,and the simulation analysis shows that the excess torque of the system is well suppressed.Secondly,the optimal control method is used to control the steering gear loading system.The optimal control problem of loading system is described as linear quadratic optimal tracking problem,which is simple and easy to implement.Because of the steady-state error problem that still exists when the method is controlled,the integral strategy is introduced to improve it,and the expected attenuation is added to the performance index to adjust the response speed.Finally,there are many nonlinear factors for the loading system,and the nonlinear control method of active disturbance rejection control(ADRC)is given,and the controller design of the active-disturbance-loading system is designed,including thestructural design and parameter setting of the controller.According to the given parameters,the simulation results show that the control algorithm is effective and the tracking performance of the system is better.