Research On Electro-hydraulic Brake Systme In The Colsed Circle Of The Transpoted Bridge Erecting Machine

The transported bridge erecting machine is a type of railway bridge equipment used in the construction of multi-tunnel section of high-speed railway,with the function of lifting,transporting,erecting bridge.It often encounters downhill in the mountainous area construction.Because of the closed hydraulic drive system,it will cause the exceeding of speeding.The existing pneumatic brake can’t fulfill the requirement of service brake,and the severe impact of mechanical braking causes serious safety risks to the construction.This topic explores a vehicle braking system applied to the closed hydraulic drive system of mobile bridge erection machine,ensuring its safety under overload conditions,and aiming at its pressure control characteristics and brake functions.The main contents of the study include:First,summarizing the characteristics of the existing engineering vehicle braking technology,detailing analysis of flow type bridge machine closed drive system working principle and load static characteristics beyond the phenomenon.On this basis,designing of a new type of application in closed hydraulic drive system of variable load balancing circuit in order to satisfy the requirement of flow type bridge machine brake sytstem.Based on the system HCD model,the relationship between damping parameters and dynamic performance of the system is analyzed.Secondly,the article focus on the control characteristics of the back pressure o f the brake balance loop.The PID controller is designed and its parameters are set.The simulation results show that the overshoot is large.Therefore,according to th e characteristics of pressure control,a fuzzy PID controller is designed to further a djust the PID parameters.Thirdly,according to the requirements and characteristics of braking,the intelligent braking control strategy is designed.In order to improve the robustness of the braking system,the brake integral synovium controller is designed according to the dynamic model of the whole vehicle,and the rationality of the MATLAB simulation verification control algorithm is carried out.Finally,the programming and hardware of brakng system are desinged.Taking a mobile bridging machine as an experimental platform,experimental study on the fixed value balance loop and the proposed brake circuit are carried out.The test results show that the designed braking scheme can meet the braking requirements and the downhill speed within 4.5km/h,in the meantime,the safety and efficiency of work is improved.