Research on the energy conversion efficiency of electro-hydrostatic actuator

Electro-hydrostatic actuator(EHA)is a key element of the power by wire system. Its essence is the pump controlled hydraulic cylinder, which mainly consists of permanent magnet synchronous motor, bi-direction hydraulic ump, hydraulic cylinder, accumulator, and other functional valves. As a power by wire actuator, the energy conversion efficiency is the main technical indicator that needs to be clarified during the EHA design phase for facilitating the design of the upper power supply module. However, there is little research on the overall efficiency of EHA. Therefore, the aim is to provide a detailed analysis of the overall energy efficiency of EHA. A certain type of EHA is taken as an example. The energy losses in the energy conversion process of the electric motor, hydraulic pump, and hydraulic cylinder are analyzed. The corresponding partial energy efficiencies and overall energy efficiency calculation models of EHA are established. The analysis accuracy of the EHA energy efficiency is verified by the test results. The research results can be used as the basis for the power evaluation and efficiency analysis of the EHA.