Dynamic Characteristic Design And Optimization Of The Novel Rotary Control Valve With Resistance To Load-fluctuation For Large Inertia Load

With the introduction of the 13th Five-year Plan,the national construction projects have more mission and the load and speed of engineering hydraulic machineries become larger and higher.As a traditional engineering hydraulic machinery,auto crane’s load is becoming larger too.A series problem have come out when auto crane works with large load.For example,the large load brings high system pressure,which can break the hydraulic components.As a result,the flow control function is hard to realize and the micro-motion characteristics of the opening and closing become worse.Meanwhile,the large load will lead inertia fluctuation,which makes the rotary control speed and flow rate unstable.So far,less rotary control valve emerge in the market,not to speak of the rotary valve that can solve the problems mentioned above.It is necessary to study and optimize the large inertia rotary control valve to meet the development tendency of the engineering hydraulic machineries.Taking the novel rotary control valve with resistance to load-fluctuation for large inertia load as the research object,this thesis analyzes the vehicle teat data and points out the two problerms of the rotary control valve,which are the flow down problem and the flow raise problem.By building and analyzing the AMESim simulation model of the large inertia system,it was found out that the unreasonable structure and opening of the main valve lead the two problems.This thesis proposes optimization scheme and designs a new valve to solve the two problems.The testbed result shows that the new valve has solved the two problems and optimized the opening delay and closing delay for 0.5s and 0.35s respectively.The new valve also maintain its characteristic of resistance to load-fluctuation and has better performance.This thesis contains six chapters,and the contents of each chapter are briefly described as follows.In chapter 1,it introduce the large inertia rotary control valve of auto crane,including the control methods and the valve products.The research significance,research methods,and determining the main contents of the research are also discussed in this chapter.In chapter 2,the working principle of novel rotary control valve with resistance to load-fluctuation for large inertia load is introduced first.Then the vehicle test data analyzing is conducted to verify its working characteristic and point its problems.In chapter 3,the large inertia rotary system AMESim simulation model is built to reappear the problems happened in vehicle test and conduct the analyzing research.In chapter 4,the reason of the problems happened in vehicle test is analyzed.The optimization design of the valve is proposed and verified in the AMESim simulation model.Also,the processing technic of the valve is analyzed briefly.In chapter 5,the working principle of rotary control valve testbed is introduced.The new rotary control valve is test.The result shows that the new valve has solved the two problems and has better performance in dynamic characteristics.The new valve also maintain its characteristic of resistance to load-fluctuation.In chapter 6,the work of this thesis is summarized,and the future research is prospected.