Simple control autotuning for PMSM drives based on feedback relay

The rapid and precise tuning of speed and current controllers is a challenging issue in modern AC drives. So far, many different solutions have been proposed in the specialised literature, but they often describe highly sophisticated methods for special, high performance applications. Conversely, this paper proposes a very simple and effective autotuning technique, for both speed and current regulators, in permanent magnet synchronous motor drives