Modelling of permanent magnet synchronous machines for simulations of transient phenomena

This paper deals with the modelling of permanent magnet synchronous machines for the simulation of transient phenomena. The differential equations are given which are used to describe the behaviour of such machines. This system of differential equations is based on a d-q-model and considers eddy currents in permanent magnets and in solid parts of the rotor which are represented by closed circuits. Most of the machine parameters required to apply the equations are identified by a FEM simulation of the machine. The approach of this identification is described. It allows to determine the effect of different rotor designs (e.g. solid or laminated rotor yoke, use of a copper shield) on the dynamic characteristics and the generated losses. In order to verify the model, its predictions for no load and starting condition are checked by measurements taken on a test motor.