Sensorless control method for the high speed permanent magnet synchronous starter-generator used in microturbine generation system

The sensorless vector control method for the high speed Permanent Magnet Synchronous Machine (PMSM) used as integrated starter-generator (ISG) applied in the microturbine generation system (MTG) is investigated in depth in this paper. For its characteristic of high rotating speed and low inductance, an improved open-loop back-EMF estimation method is proposed to estimate the position and velocity of the high speed PMSM. The tracking differentiator is used instead of the classic differentiator to overcome the problem of noise amplification. The variable parameter low-pass filter optimized based on the velocity is adopted to filter the estimated back-EMF. Moreover, the estimation errors caused by the low-pass filter and sampling delay are also compensated. The effects of voltage distortion caused by dead time on the estimation accuracy are weakened by dead-time compensation. Based on the proceeding estimation, the sensorless vector control system for the high speed PMSM used in a 30 kW MTG is designed and implemented. The simulation and experimental results show the proposed sensorless vector control method is simple, practical and possessing good estimation accuracy at large-scale speeds. It can satisfy the requirements in terms of fast and stability during the operation of microtubine generation system, and ensure that the system has good static and dynamic performance.