Design and working mode analysis of dissimilar redundant actuator system

The dissimilar redundant actuator system gets rid of central hydraulic power and avoids the common fault effectively, which is consistent with the development trend of more electric aircraft. Based on the load characteristics matching method, a dissimilar redundant actuator system made of electro-hydrostatic actuator with variable motor speed and electro-mechanical actuator was designed. The overall mathematic model was established by considering both of the air load and connecting stiffness of control surface. Then three typical operation modes were analyzed theoretically and simulated contrastively, and the switch transience between these operation modes under the air load was presented, too. Meanwhile, the zero current control method in the current loop of motor was proposed to the no-load operation mode. Its controller was simple to realize and the switch was rapid and reliable. The analysis results provide the theoretical evidence to system design, operation mode and fault switch method of dissimilar redundant actuator system.