Power matching method of parallel hybrid excavator

Abstract

The currently used control strategy of hybrid excavator does not consider the power matching between the power sources, so it is hard to guarantee the control effect. Based on the analysis of hydraulic excavator working condition and the development of a parallel hybrid excavator model, the concepts of hybridization, optimum hybridization and dynamic optimum hybridization were introduced, and the matching degree between the main power source and the auxiliary one was described. The influences of hybridization factor (HF) on the control strategy, fuel economy and drivability were investigated. A new method to decide the HF which is based on the load of the excavator and aims to improve the fuel economy was presented. The simulation shows that the method can get a suitable HF which can guarantee the control effect without the limitation of the power sources, and it can get the best fuel economy without sacrificing the drivability of the hydraulic excavator.