Abstract: Integrated electrical hydrostatic actuate system has the advantages of both traditional hydraulic system and direct drive electrical mechanical system, and it can be modularized easily. This paper describes the structure and operating principle of EHA , and it gives the specific requirements of the system design and selective principles of the motor, pump and hydraulic cylinder. Furthermore, it creates the mathematic model of each module. Simulation results show that the EHA can meet modern aircraft’s requirements to the actuate system, and it can be used widely in the future PBW flight control system.

Key words: electrical hydrostatic actuator(EHA), hydraulic, integrated, power by wire(PBW), simulation