This paper shows a wound rotor doubly fed induction machine in which the typical brushes and slip-rings are substituted by rotary transformers. The advantages of rotary transformer usage, the doubly fed induction machine operation and the dimensioning of a radial rotary transformer are the main aspects presented in this study. The use of analytical equations is a very interesting resource for the development of industrial software for the calculation of this kind of device. Comparison between simulated and measured results shows the good approximation of the steady-state model with the reality of this equipment.
Alternating current machines; brushless machines; prototypes; rotary transformer; transformer calculation
