Study of high-reliable differential dual-redundancy EMA without load-averaging controller for aircraft

Dual-redundancy EMA is studied in this paper for improving the reliability and safety of aircraft. The differential sport synthesization scheme is proposed for solving load-unbalance problem when operating with the mode of dual-redundancy, which is a mechanical structure to turn two outputs into one output without load-averaging controller, and this structure can decrease the design difficulty of controller to improve the stability and reliability of system, moreover, local-redundancy design is done in this paper, it can still guarantee some redundancy in system when some faults appear in one channel. In addition, in order to simplify design, the method of truth-table is adopted to code 6 PWMs for three phase VSI bridge, moreover, the rotator signal and PWM are used together to forms a BIT module for system, and it can realize fault detection and diagnosis for dual-redundancy EMA. The PD controller with variable parameters is presented to compensate nonlinear factors of system. The experimental results validate its system design, and show that the prototype of DR-EMA has fine performance, high stability and reliability