Dynamic Control Of The Permanent Magnet Assisted Reluctance Synchronous Machine

The reluctance synchronous machine (RSM) has higher torque density and efficiency. Because the absence of rotor currents, leads to insignificant rotor losses and the rotor manufacturing cost for the RSM is relatively low, and a simple vector control scheme, the RSM received more attention of many experts and scholars at home and abroad. But because the RSM has a lower power factor and its performance deteriorates fast in the flux-weakening region, and so on. To address this problem, permanent magnets (PMs) can be placed inside the flux barriers of the reluctance rotor, proposed permanent magnet assisted reluctance synchronous machine (PMA RSM) concept.This thesis is about the dynamic control of a permanent magnet assisted reluctance synchronous machine. The PMA RSM (110kW) is a traction machine and is ideal for the use in electrical rail vehicles. The mathematical model of the PMA RSM is derived and explained its principle. Then current controller and speed controller are designed. The current controller can guarantee stability of PMA RSM, and can be used for any method of current control, i.e. constant field current control (CFCC) or constant current angle control (CCAC). An accurate simulation model for the PMA RSM is obtained using results from finite element analysis (FEA), and is verified by simulation. The speed controller designed in this thesis is a normal proportional integral controller, and is verified by simulation. To improve the dynamic performance of the PMA RSM, a load torque observer with compensation current feedback is investigated. Two observer structures are considered, namely the reduced state observer and the full state observer. The accurate simulation model of the PMA RSM is used to verify the operation of the observer structures. Both observer structures are implemented practically and practical results are shown.