Multiple Hydraulic Power Flow Coupling Matching System And Its Application

In the recently years, as the main energy of soaring oil price is rising,energy issues have directly restricts the development of international economy. Hydraulic excavator is the main equipment of the national infrastructure, ir’s used range is greatly wide, complex working condition, work cycle, load sharp changes in engine often work in the inefficient zone, bad working condition, poor fuel economy and emissions. In order to solve this problem various countries related to improving the efficiency of hydraulic excavator. At present, the hybrid technology has been widely used in automobile industry, has been widely used in the field of engineering machinery, mainly for hybrid dynamical system is studied, the battery power density is small, expensive shortcomings restricting its development directly. Therefore, this paper presents a series hybrid hydraulic excavator hydraulic hybrid system as a driving force system, the accumulator can absorb engine to overcome the additional power of the load, and can recycle hydraulic mining potential energy loss caused by motorized arm down. Based on the series hydraulic hybrid system as the research object, this paper’s main research content is divided into the following five parts:(1) In this chapter through the analysis research of the present status of the hydraulic excavator energy saving, and the hybrid technology in the field of mechanical engineering application problems, put forward the series hydraulic hybrid system design scheme, and puts forward series hydraulic hybrid system the overall design goal.(2) This chapter we through the series hydraulic hybrid system key parts characteristics were analyzed, and establishes a series hydraulic hybrid system key parts matching parameters design goals, and set up the engine, the bidirectional variable pump/motor, hydraulic accumulator of the specific parameter matching method, the design selected the series hydraulic hybrid system specific parameters and model of key components.(3) Through the series hydraulic hybrid system structure is simplified, the analysis engine, hydraulic accumulator, the mechanical properties of the bidirectional variable pump/motor, fluid properties, set up the the key components of series hydraulic system mathematical model, and the corresponding simulation model is set up in MATLAB/SIMULINK.(4) At present,in the hybrid power system is widely used single working point, double working point, etc., on the basis of control strategy, put forward suitable for tandem type hydraulic hybrid system based on the condition of fixed set-point control strategy. Through the analysis of the control process, to establish the corresponding MATLAB/SIMULINK simulation model.(5) In this part we respectively in overloading condition, working condition of overloading and light load conditions to verify series hydraulic hybrid system can meet the dynamic performance of the hydraulic excavator working cycle, and with the common hydraulic excavators fuel quantity under the same working conditions compared to series hydraulic hybrid system than ordinary oil excavator oil-saving rate above20%. Series hydraulic hybrid system can meet the design expectations, the overall design of the goal.