System-on-Chip sensorless control of PMSM combining signal injection and flux observer

This paper presents an FPGA based System-on-Chip (SoC) sensorless controller for Surface Mounted Permanent Magnet Synchronous Machines (SMPMSM). A hybrid sensorless controller combining the signal injection method and a linearly compensated flux observer is proposed. Using Delta-Sigma A/D converter and FPGA oversampling technique, this paper realizes a high performance high frequency (HF) injection sensorless control which needs lower HF current response and introduces lower acoustic noises. The linearly compensated flux observer based on back-EMF is used for sensorless control in high speed range. The flux observer exhibits high dynamic and steady state performance and is robust to parameter variation. The whole control system is designed and implemented in a single chip. The proposed controller exploits the fast computation and flexibility of FPGA. Experimental results demonstrate that the developed sensorless controller has high performance in the whole speed range.