Optimal design methodology of a three phase rotary transformer for doubly fed induction generator application

Rotary transformers can be used to provide magnetic coupling to the rotor circuit of a doubly fed induction generator. This topology eliminates the need for slip ring and brush assemblies thus reducing the maintenance required. This paper presents an analytical method for determining an optimal design of a rotary transformer. The methodology is used to design a 3 kVA three phase transformer which is validated using a FEM simulation package. Also, a study of suitability in terms of size at different power levels is conducted.