Research And Design On The Energy Saving Control Of The Wheel Excavators’ Driving System

In the world of advocating energy-saving, the study of excavator energy-saving technologies has become a promising issue. Although the application of the wheel hydraulic excavator driving system is becoming increasingly popular, studies on the engine speed, the dynamic matching of driving speed and the energy-saving of hydraulic excavator driving system are still inadequate. This thesis attempts to study the wheel hydraulic excavator’s driving system and propose ways for saving energy through theoretical analysis and experimental research.Based on the analysis of the typical condition of the wheel hydraulic excavator’s driving system, the main reasons of its energy loss are figured out. The incomplete match between the engine and the pump, the throttling losses and losses resulting from the efficiency of the machine and hydraulic transfer would all contribute to the energy loss of the wheel hydraulic excavator’s driving system.It is proposed to dynamically control the hydraulic pump power according to the engine speed and conduct segment control of the engine’s invariant point for energy-saving on the basis of the engine-pump’s control mode and the hydraulic driving motor’s mechanism of variable control.Concerning the control scheme of the engine-pump’s dynamic match, studies are made on the overall control strategy, the control process, the dynamic control of the engine throttle’s speed, the electric proportional pilot valve and the control strategy of the engine-pump-motor’s dynamic matching. The curve of motor pressure and its output torque and the curve of motor pressure and the driving speed of wheel hydraulic excavator are worked out according to the characteristics of the motor’s variable control. As required by the control strategy of energy-saving, the hardware design of the control system, the optimized design selection of the main components, the software design of the control system are worked out.Finally, based on the SWE130W wheel excavator completed the study test, The test result shows that its efficiency has increased by4.43%. So the strategies for improving the wheel excavator’s driving system have been proved to be rational and efficient.