Power control of brushless doubly-fed reluctance drive and generator systems

A new algorithm for shaft position sensor-less independent control of real and reactive power of the Brushless Doubly-Fed Reluctance Machine (BDFRM), an emerging competitive for applications with limited variable speed ranges (e.g. pumps or wind turbines), is proposed and experimentally verified in this paper. The algorithm is inspired by the fundamental operating principles of the machine and does not depend on any parameters. Therefore, it is more robust than model-based control approaches which often suffer from sensitivity issues and performance trade-offs associated with machine parameter variations or their inaccurate identification. In turn, the considered control method merely relies on the grid-connected winding voltage and current signals. Practical studies including speed tracking, power factor regulation and load response have demonstrated high performance of the scheme on a custom designed 1.5 kW prototype.