Research On Shunting Control For The Load Sensing System With Many Actuators

With increasingly high demand for energy-saving in construction machinery industry,application of load sensitive system is more and more widely. For single actuator system,load sensing system can meet the job requirements satisfactorily. However, for singlepump driven actuators load sensitive systems, when the multiple actuators require actionsimultaneously and maximum flow of the pump is insufficient to provide the sum of therequired flow of all actuators, the ordinary load sensing system will appear high load-sidepressure compensator does not work, so as to the high load associated actuator speedreduce or even stop. In view of this phenomenon, this article studied the shunt controlmethod of single pump driven actuators load sensitive system.This paper through studying the inadequacies of single pump driven actuators loadsensitive system, analyzed the principle of diversion control, get a new diversion controlmethod that can solve the insufficient flow and applied to forklift’s system. Make theCPCD160diesel forklift as the research object, first of all, introduced the each action ofthe forklift briefly, understand the conditions of every action, based on the above analysisdid design calculations and basic component selection of the action of the load sensitivesystem.Secondly, using AMESim software established every element’s simulation model ofthe designed load sensitive system. Structuring the working part of the simulation modelof hydraulic system, combined with the actual working condition to carry on the designcalculation and simulation parameters, and analyze the simulation curves.In view of the single pump driven actuators load sensitive system put forward a newmethod of shunting control. With two actuators system as an example, carrying on thesimulation analysis of two cases and through comparison proved the shunting controlmethod is correct. The shunt control method is applied to forklift system, simulationanalysis is carried out on different working conditions, verified the shunt control methodcan satisfy the composite action of coordination.Finally, the controller in single branch control system is optimized, simulated conventional PID and two degree of freedom PID control mathematical models of thesingle branch control system respectively.The simulation results are compared.Then, twodegrees of freedom PID controller is added to two actuators load sensitive systems withshunt control for validation.