On the steady-state characteristics of cascaded doubly-fed induction machines: Potentialities of integration in wind generating systems

Cascaded doubly fed induction machines (CDFIMs) could be of interest for wind energy conversion systems. The investigation of their steady-state characteristics is currently considered as a state of the art topic. Within this trend, the paper is aimed at the analysis of the steady-state operation of CDFIMs considering both similar and different rotor phase-sequences. Following a recall of the CDFIM basis, its a-b-c model, with the motor convention accounted for, is derived. Its schematic bloc diagram is then established and implemented which enables a simulation-based analysis of its steady-state characteristics under motor operation. While the steady-state analysis of the generator operation is achieved by experiments carried out on a test bench where the wind turbine is emulated by a DC motor.