A fractional order PID control strategy in active magnetic bearing systems

Abstract

Active Magnetic Bearings (AMBs) are broadly utilized for high angular speed machines such as turbo-machinery, compressors and high speed motors. In AMBs, the rotating parts run without physical contacts with the moving parts. This reduces maintenance costs and minimizes friction. Generally, the applied loads cause extra gyroscopic effects on the rotating parts especially under high-speed operation. Although conventional PID controllers are widely employed in these systems, they experience some stability problems under high dynamic operations. In this paper, the design of an active magnetic bearing system based on fractional order PID (FOPID) controllers to enhance system dynamics and stability is introduced. The suggested controller gains are optimized utilizing particle swarm optimization (PSO) approach. An ordinary AMB system framework with four radial bearings is used to assess the suggested FOPID controller against routine PID controllers. The system current limitation, overshoot constraint, and time specifications requirements are deemed in the optimization technique.