Research On The Electro Hydraulic Digital Control System Of Manhole Cover Rolling Fatigue Test

Check the well known as the manhole,manhole cover manhole is ground facilities.The plastic material used for the production of manhole covers is a trend in recent years.As plastic manhole covers have the advantages of energy saving,environmental protection and recycling,they are suitable for the needs of sustainable development.However,the plastic manhole cover corresponding detection is not perfect,because of plastic material problems,it is necessary to plastic manhole cover rolling fatigue test,In this paper,plastic manhole cover rolling fatigue test system as the research object,according to the actual condition of plastic manhole cover,designed rolling fatigue test scheme,the digital electro-hydraulic control technology applied to the plastic manhole cover rolling fatigue test system,using incremental digital valve design of the digital electro-hydraulic loading force and speed control system.This paper expounds that plastic manhole covers are widely used because of their many advantages.Because of their special materials,the necessity of rolling fatigue test for plastic manhole covers is brought forward.Through the analysis of loading mode,development status and development trend of test machine,the requirement of test equipment with low price and satisfying performance is pointed out.Through the comparison of direct and indirect electro-hydraulic digital control technology,the development prospect of direct digital control technology is pointed out.According to the actual use of plastic manhole cover in stress condition,according to the manufacturer's request and the literature on parameter setting,the implementation scheme and the main parameters of the experiment,and the design of the digital electro-hydraulic control system.Through the selection of incremental digital valves,hydraulic pumps,hydraulic cylinders and sensors,the mathematical model of speed control and loading pressure control is established without neglecting the key factors in the system.The dynamic response and steady state response of the speed control system and the load pressure control system are simulated and analyzed by using MATLAB/Simulink simulation software.The fuzzy control algorithm with PID phase correction series,a fuzzy PID controller is designed to improve the system response speed and stability,reduces the overshoot and steady-state error of the system,to ensure that the control system can meet the design requirements.The simulation shows that the electro-hydraulic control loading system designed with incremental digital valve has stable operation,small overshoot,fast response and small steady-state error.It meets the requirements of roller fatigue test for plastic manhole cover.