Study On Energy Saving Of Boom Hydraulic System In Hybrid Excavator

With the rapid development of economy, hydraulic excavators are more andmore widely used in the construction of the infrastructure of the country, such asparticipation in earthwork construction, demolition and geological disaster relief, etc.The condition of energy shortage and environmental degradation in the currentsituation make the shortcomings of energy consumption and emission of hydraulicexcavator abrupt. So it is of important practical significance to study the energyconservation and emissions reduction of hydraulic excavator.In order to achieve the goal of energy conservation and emissions reduction, themajor construction machinery companies have draw lessons from the successfulapplication in the field of car hybrid technology, and designed hybrid hydraulicexcavator. Boom potential energy recovery technology, which is based on the hybridhydraulic excavator, is an important direction in the study of energy saving onexcavator. In this paper, the main research contents are based on Hitachi ZX70excavator, are as follows:1. According to the working conditions of hydraulic excavator, a scheme ofenergy recovery on boom potential is developed based on the hybrid system, and theprinciple of potential energy recovery system diagram is worked out, and so is withthe working principle and control method of the scheme.2. Local coordinate systems of hybrid hydraulic excavator’s boom, arm andbucket are set up respectively in the D-H coordinate system. The kinematics model ofeach institution are also established by the geometric and physical relations, and adynamic simulation model of excavator device is built based on ADAMS.3. The mathematical model of hydraulic cylinder of boom, quantitative pistonmotor, variable piston motor and displacement control mechanism are built. And thenthe potential energy recovery system is established in the Simulink module of Matlab.4. Through the simulation study of potential energy recovery system, The boom piston rod speed, rodless cavity pressure for boom hydraulic cylinder, and angular velocity ofvariable motor on the open area of proportional servo vale and the open area of proportionalthrottle valve are analyzed. This paper also analyzed the effect of PID controller for the potentialenergy recovery system. And it is concluded that the energy recovery rate of potential energyrecovery system of the arm on the excavator was54%.