A novel correction method for a low cost sensorless control system of IPMSM electrical drives

In this paper a novel correction method for sensorless Field Oriented Control System of Brushless internal Permanent Magnet Electrical Drives is introduced discussed and experimentally validated. The novelty of this control system is the estimation of rotor speed and angular position is based on the back electromotive force space vector determination, without the aid of voltage probes. Actual voltage signals needed for estimation are replaced with the reference ones given by the current controller. This choice obviously introduces an error that have been vanished by means of a new compensating function or with the aid of data coming from experimental tests. Experimental verifications of the proposed sensorless control system were made with the aid of a flexible test bench for Brushless Motor electrical Drives. The test results presented in the paper show the validity of the proposed low cost sensorless control system and, above all, underline the good performances of the sensorless control system also with a so reduced equipment.