Research On Power System Of Hybrid Hydraulic Excavator

The hybrid technology of hydraulic excavator is an effective technological solution to reduce fuel consumption and improve emission. The field of research has just started in China. This dissertation studied the power system of hybrid hydraulic excavator, through the establishment of the power system model and simulation with the control strategy combining the working conditions of excavator. It is improved in theoretical level that the power system of hybrid hydraulic excavator is superior to ordinary excavator on the aspects of working performance, fuel efficiency and etc. The importance and application prospect of hybrid hydraulic excavator are also expressed. The dissertation is divided into the following sections:(1) Introduction. Introduced the research significance of hybrid hydraulic excavator and its power system, and explained the field of study at home and abroad. Obtained the shortage of the field of study in accordance with the current study, and explained the research content and key points of this dissertation.(2) The layout and parameters match of hybrid hydraulic excavator power system. Adopted the parallel structure by comparing the structure of three kinds of hybrid power system layout and considering characteristics of excavator, and matched the parameters of engine, motor and batteries according to the requirement of the power system of hybrid hydraulic excavator.(3) The research of hybrid hydraulic excavator dynamic model of diesel engine. Quoted the modeling method of the p-w based transient dynamic model of engine, and built the transient dynamic model of engine for hybrid hydraulic excavator, which supplied a good platform for the research of control strategy of power system.(4) The simulation research on hybrid hydraulic excavator power system. Introduced the power system model of hybrid hydraulic excavator and its load conditions, adopted multi-work-point control strategy, compared the power system model of hybrid hydraulic excavator with ordinary excavator engine on simulation research, and proved that hybrid power system is superior to ordinary power system on the aspects of stability, fuel efficiency and etc.(5) Designing and building the experiment bench of hybrid hydraulic excavator. Introduced the structure and system function of the experiment bench, and explained respectively the section of hybrid power system and hydraulic simulating load system. The process of designing and building is expressed by drawings and pictures.