Sinusoidal current drive system of permanent magnet synchronous motor with low resolution position sensor

The high performance drives of the sinusoidal back-EMF type permanent magnet synchronous motor can be achieved by the current vector control, where the sinusoidal currents flow according to the rotor position and the current phase is suitably controlled according to the operating condition. In such a high performance drive system, a high resolution position sensor is desired. In this paper, a sinusoidal current drive system with a low resolution position sensor is proposed. The high resolution position information is obtained by the position estimating circuit from the signal of a low resolution position sensor. The steady-state and transient characteristics are examined by several experiments, then it is confirmed that the sinusoidal current drive and the high performance current vector control can be achieved by the proposed drive system.