Fault tolerant control of active magnetic bearings

A nonlinear model of a Rolls-Royce turbomachine's rotor supported by active magnetic bearings (AMBs) is presented. The model has the capability to model magnetic bearing systems of a variety of different configurations. A multiobjective genetic algorithm (MOGA) is used to design PID controllers for the AMB system with five different bearing configurations. A centralised fault compensation scheme is demonstrated and shown to perform more effectively than a decentralised control system without such a scheme. The fault tolerance characteristics of the five different bearing structures are compared under both decentralised and centralised control.