Research On Pump-control-motor Closed-circuit Speed Governing Control System Characteristics

With the mobile hydraulics towards the development of large scale and heavy duty, and the complex working conditions, the requirements of driving system have been highly increased. Most of the driving systems for mobile hydraulics have been adopted pump-control-motor closed-circuit system. Related technical research in foreign countries has been very mature and extensively, but the domestic research on the issue is relatively backward and also far behind the international level. Therefore the research of pump-control-motor closed-circuit for mobile hydraulics driving system and key hydraulic components will have great significance.The pump-control-motor closed-circuit for mobile hydraulics driving system is the research object of the scientific dissertation. The static mathematic model was set up by using force equilibrium equation and flow continuity equation. The dynamic simulation model was built up in simulation software. The influence factors to the dynamic performance of the system had been analyzed in simulation environment. Towards the above factors, the conventional PID controller and self-tuning fuzzy PID controller based on disturbance observer were designed and analyzed in simulation software. The simulation results proved that the latter control effect was better than the former. On the basis of theoretical analysis, the comprehensive test bed of pump-control-motor closed-circuit system had been manufactured. The influence factors to the dynamic performance of the system had been tested. The test results and simulation results were in the same trend. Finally, the test and research to the static and dynamic performance of the variable pump had been taken.This scientific dissertation mainly include the following aspects of content:In chapter 1, the pump-control-motor closed-circuit speed system was discussed. The research status and development trend of the system for mobile hydraulics driving system were briefly introduced. Then the subject significance, the research methods and research content were put forwards.In chapter 2 and 3, the mathematical model of the pump-control-motor closed-circuit speed system and the system transfer function had been set up. The conventional PID controller and the self-tuning fuzzy PID controller based on disturbance observer had been built up.In chapter 4, the simulation model of the pump-control-motor closed-circuit speed system had been built in AMESim simulation software. The influence factors to the dynamic performance of the system had been analyzed in simulation environment. The simulation analysis of the influence factors to the dynamic performance of the system had been made in MATLAB simulation software using the above two controller. The simulation results had been compared.In chapter 5, the comprehensive test bed of pump-control-motor closed-circuit system had been manufactured. The influence factors to the dynamic performance of the speed system had been research in the test environment. Finally, the static and dynamic test of the variable pump had been taken.