Research On The Characteristics And Experimental Techniques Of Construction Machinery Hydraulic Chassis In Fluctuating Load

In fluctuating load conditions, the power of construction machinery hydraulic chassis islow, economy is poor, and the system pressure is volatile. For these questions, based on thespecial fund for basic scientific research of central colleges and basic research supportprogram of chang’an university, and rely on the construction machinery hydraulic chassissimulating test bench of chang’an university, the construction machinery hydraulic chassischaracteristics and experimental techniques were researched. In order to provide scientific andadequate theoretical and experimental basis for improve the dynamic performance ofconstruction machine and laboratory equipment and methods. In this paper the research workis focused on the following aspects：i. Analysis of the composition and technology programs for the simulating drivingsystem, simulating loading system, control system, test system, and the auxiliary devices ofthe construction machinery hydraulic chassis simulating test bench, and conduct specificexperiments. Experimental results show that technical specifications of the test bench meetthe design requirements, the system design is reasonable, the test bench can simulate a varietyof construction machinery drive system in different working conditions of hydraulic chassissystems, also in experimental, provide a basis studies.ii. The transmission efficiency of the construction machinery hydraulic chassis drivesystem was studied. The impact of the speed, displacement and system working pressure ofhydraulic pump and hydraulic motor on the transmission efficiency of the hydraulic systemwas analyzed, and on this basis, the experimental study was conducted. And a high efficiencyof the parameter matching condition of hydraulic drive system has was proposed, for theanalysis of system characteristics and a reasonable match provide a frame of reference.iii. Through simulation analysis and experimental research on the test bench loadingsystem which based on secondary regulation technology was studied. The mathematicalmodel of the second component was established, the simulation analysis was conducted andsome specific experiments were made. Also, it can provide theoretical and experimental basisfor the follow-up study and enhancing the dynamic and static characteristics of the simulationloading system with secondary regulation.iv. The fluctuating load and simulation methods were analyzed and studied during theoperation of construction machinery. In order to meet the dynamic performance experimentsof test bench, as well as simulation analysis needs of the system dynamic characteristics, inthis paper, the processing method of bulldozer working resistance measurement data were improved and perfected, and the simulation method of construction machinery fluctuatingload was proposed, and a function expression which describe the trend items of fluctuatingload was given. And the factors which affect the change of the trend items of fluctuating loadwere analyzed. Through AMESIM simulation software, the fluctuating load of constructionmachine was simulated, and the simulation method was given.v. Through a combination of simulation and experimental research method, in fluctuatingload conditions, the accumulator parameters on the impact of the drive system characteristicsof construction machinery hydraulic chassis was studied. The force of accumulator wasanalyzed, and the simulation model of construction machinery drive system with accumulatorwas established, by using AMESIM simulation software. It also conducted the simulation instep load and fluctuating load conditions. In order to improve the characteristics of theconstruction machinery hydraulic drive system in fluctuating load conditions, the methods ofsetting the parameters of the accumulator were proposed. For the step load and loadfluctuation of the simulation analysis, and for a specific experimental study, the experimentalresults verify the theoretical analysis is correct.vi. The dynamic load control methods of construction machinery hydraulic chassis werestudied, and some of the control methods were summarized. The theory and algorithms ofhydraulic pump DA control and motor HA control was studied, and the control procedureswere written. At the same time, some specific experiments were conducted. Also, it canprovide theoretical and experimental basis for construction machinery hydraulic chassisdesign in fluctuating load conditions.