Simulation Analysis of Potential Energy Recovery System of Hydraulic Hybrid Excavator

摘要

A new hydraulic hybrid excavator potential energy recovery system is proposed in this paper. The energy recovery system uses threechamber cylinders (TCCs) and accumulators to recover potential energy during work cycle. Within this structure, there is no throttle valve in the primary loop, and the recovered energy is stored in the form of hydraulic energy. Hence, energy loss of throttle valve and energy conversion process are avoided, and energy efficiency is improved. The mathematical model is established to analyze dynamic and energy recovery characteristics. From simulation analysis, the usage of accumulators and TCC influences the dynamic response and stability. The increase of accumulator volume weakens the control performance but heightens the stability. When the cross sectional area of the TCC increases, the control performance of the system are improved. In addition, the maximum power and energy consumption of pumps and engine with different accumulator volumes and different TCC diameters are obtained. Also, the maximum power and energy consumption of each pump and engine in different working conditions are obtained and compared with those without potential energy recovery system. According to the comparison, the potential energy recovery system can reduce the maximum power and energy of engine by 50%.