Analysis of the dynamic performance of an electro-hydrostatic actuator and improvement methods

作     者：Zhihui LI Yaoxing SHANG Zongxia JIAO Yan LIN Shuai WU Xiaobin LI 

作者机构：School of Automation Science and Electrical EngineeringBeihang UniversityBeijing 100083China Science and Technology on Aircraft Control LaboratoryBeihang UniversityBeijing 100083China 

出 版 物：《Chinese Journal of Aeronautics》 (中国航空学报（英文版）)

年 卷 期：2018年第31卷第12期

页      面：2312-2320页

核心收录：

学科分类：08[工学] 0802[工学-机械工程] 0825[工学-航空宇航科学与技术] 0801[工学-力学（可授工学、理学学位）] 

基　　金：the National Natural Science Foundation of China(No.51475020) the National Key Basic Research Program of China(No.2014CB046400) 

主　　题：Dynamic characteristic Motor-pump group Power requirement Rotational inertia 

摘      要：As a kind of actuation mechanism for power-by-wire(PBW) actuation systems of more/all electrical aircraft, an electro-hydrostatic actuator(EHA) is a highly integrated local hydraulic actuation system. It is a volume control system consisting of a motor, a pump, an actuator, etc.,which has features of high efficiency and reliability. However, the poor dynamic characteristic is one of the main factors restricting its wide application in aircraft. In this paper, the reason for the poor dynamic characteristic of an EHA is revealed from the perspectives of the natural frequency characteristic and the power requirement, respectively. In other words, the insufficiency of the motor output power at a high frequency is the main factor causing the poor dynamic characteristic of the system, and methods which include increasing the maximum output torque of the motor, reducing the rotational inertia of the motor-pump group, and adopting a double-motorpump group configuration are proposed in this paper, by which the dynamic characteristic of the system can be improved. The feasibility of those methods are verified by simulations. Finally, the dynamic characteristic is tested on an EHA prototype, and results show that saturation of the output torque of the motor is the main factor restricting the dynamic characteristic of the EHA system.