In this paper,a novel hybrid Three-Redundant Electro-Mechanical Actuator(EMA)system is proposed,which is mainly composed of two automatic brusliless DC motor(BLDCM)drivers and one manual BLDCM driver.Each driver is in charge of the control of one brushless DC motor.At any tine,only one set of drivers works to realize the accurate position control.The rationality of the system is analysed then.Compared with the traditional redundant EMA with parallel structure,this system exhibits the advantages of more simple structure,more flexibility control and higher reliability.Two kinds of the fault tolerant operating modes are presented.The result is elicited by analyse and calculation that the hybrid Three-Redundant EMA improves the reliability of the system remarkably.
