Alternatives in simulating electrical machine dynamics

The current electric machine modeling approach is based on Park transformation to convert the original time domain equations into a new reference frame, which rotates around the stator with a constant speed, creating a set of fictitious variables. However, from the simulation and control perspective only the actual (phase) variables are needed. Consequently, in control schemes and in simulating real power networks, one is forced to transform back current and voltage variables to the phase reference frame. The authors´ proposed method directly uses phase variables avoiding any transformation at all. The main benefit of such an approach is a simpler mathematical model and increased speed of calculations. Considering large-scale power systems, the speed of calculation becomes a very significant factor. This paper presents the basic equations of their model for simulating synchronous machine dynamics in phase variables.