Achieving sensorless control for the brushless doubly-fed induction machine

The brushless Doubly-Fed Induction Machine, without brushes and slip-rings, is regarded as an attractive alternative to the conventional Doubly-Fed Induction Machine in terms of reliability. This paper presents a sensorless field oriented control strategy for the Brushless-DFIM, which further increases its attractiveness as a drive system.With the use of a straightforward and alternative time-dynamic Brushless-DFIM model, a complete Brushless-DFIM based drive is modelled and used for the development of the sensorless control strategy. The developed sensorless control strategy is implemented in an experimental set-up. Simulation and measurement results demonstrate that the developed sensorless control strategy can control the Brushless-DFIM in a stable and responsive manner over its full operating speed range. In this way, a fully functional sensorless control strategy for the Brushless-DFIM is demonstrated for the first time in literature.