A current sensorless drive system of a synchronous motor with a low-resolution position sensor.

High-performance drive of synchronous motors such as a permanent magnet synchronous motor and a synchronous reluctance motor can be achieved by current vector control. In such drive systems, the armature current is controlled as a sinusoidal waveform based on rotor position information from a high-resolution position sensor, and the current vector (d- and q-axis currents) is suitably controlled by current feedback control. This paper proposes a current sensorless drive system with a low-resolution position sensor in order to simplify the SM drive system. High-performance current control is achieved in the proposed drive system, where the current sensors are eliminated and the simulated currents are used for current control. The low-resolution position sensor is used instead of a conventional high-resolution position sensor, and the higher position information is estimated. The steady-state and transient characteristics are examined in several experiments with respect to the synchronous reluctance motor and the interior permanent magnet synchronous motor. It is confirmed that sinusoidal current drive, high-performance current vector control, and speed control can be achieved by the proposed drive system. © 2002 Wiley Periodicals, Inc. Electr Eng Jpn, 141(4): 34–43, 2002; Published online in Wiley InterScience (<URL>www.interscience.wiley.com</URL>). DOI 10.1002/eej.10072 [ABSTRACT FROM AUTHOR]