Highly efficient constant-speed drive system based on a doubly fed permanent magnet synchronous machine

In this paper, a highly efficient drive system for constant rotational speed applications, including a doubly fed permanent magnet synchronous machine (DFPMSM), will be presented. Due to loss minimization, most of the stator windings of the DFPMSM are directly fed by the electrical grid, while only some of the stator windings are fed by a low-power inverter to stabilize the complete drive system.