Distributed Control of Redundant Electromechanical Actuation Systems

Abstract

This paper presents a distributed control strategy for redundant electromechanical actuation systems, aiming to achieve both accurate position regulation and torque equalization among actuators. The study considers systems with multiple identical electromechanical actuators (EMAs), typically two, driving a shared rotational load. For practical implementation, a multi-loop control structure based on proportional-integral (PI) controllers is employed; however, such PI-based loops alone are generally insufficient for torque equalization. To address this, a consensus-based distributed control scheme is proposed, where local controllers exchange reference current information via communication links to coordinate torque outputs. Theoretical analysis shows that the scheme achieves position regulation equivalent to that of a single EMA while ensuring torque equalization. The effects of measurement offsets were also examined, and a method was proposed in which controllers share offset information to eliminate position regulation errors caused by these offsets. Simulation results are provided to validate the proposed approach.