Position sensorless vector control of the brushless synchronous motor

The position sensorless vector control scheme for the brushless excited synchronous motor based on the IGCT converter is presented in this paper. Since the instantaneous excitation current cannot be directly measured in this application, an adaptive rotor position and speed observer, which does not rely on the explicit estimation of the excitation current, is developed for the brushless excited synchronous motor. The roughly estimation of the excitation current is based on the average model of the excitation machine and the rotating rectification diode. The control algorithms are implemented and validated in a 2*27MVA motor pump-back test bench.