Vector Model Utilization for Nested-Loop Rotor Brushless Doubly-Fed Machine Analysis, Control and Simulation

This paper presents different applications of a vector model developed by the authors in Brushless Doubly-Fed Machine (BDFM) studies including analysis, control and simulations. The BDFM considered consists of a nested-loop type rotor. The vector model, which considers all the loops in each rotor nest, is derived using BDFM coupled-circuit model equations and by applying appropriate vector transformations. Three vector transformations are employed for the derivation of vector model corresponding to two three-phase windings in the stator and the rotor circuit. Each transformation consists of an angle which is, in general, unspecified and must be assigned appropriately depending on the application of vector model. The paper demonstrates proper assignments of the transformation angles for BDFM operation analysis, control synthesis and simulations.