Iron loss modeling by complex inductances for steady state simulation of electrical machines

This paper deals with modeling and simulation of rotating field machines for steady state conditions. Two special machine types are considered - asynchronous induction machine with squirrel cage rotor and permanent magnet synchronous machine. A system model for steady state operation of both machine types is built based on a single phase equivalent circuit. The two most important types of iron losses in electrical machines are studied - eddy current and hysteresis losses. In this context, a new term, namely the complex inductance, is introduced. By the use of a complex inductance one is able to account for iron losses in electromagnetic circuits and to describe both eddy current and hysteresis losses separately. With respect to both types of iron losses, the existing equivalent circuits are expanded by complex inductances. Finally, the resulting models can be used for steady state simulations considering the essential losses of rotating field machines.