A new approach for a complete and ultrafast analysis of PMSMs using the arbitrary injection scheme

This paper proposes a new method for the complete and ultrafast measurement of magnetic properties of PMSMs. The measurement results are utilized for sensorless control of a multiple salient motor. The method is able to determine the machine's inductance parameters dependent on the load state and on the rotor position in minutes for the PMSMs whole operating range. The presented scheme is based on an encoderless predictive torque control algorithm firstly published by Landsmann et. al. [1], that evolved to a field-oriented encoderless control algorithm [2]-[4]. The scheme enables the user to identify and to separate magnetic influences from different causes, i.e. permanent magnet flux, the current induced magnetic flux and their interaction in an operating machine. The method is derived geometrically from an online mean admittance estimation and validated by simulation and experiment. A surface mounted PMSM is then investigated with this new measurement method, the harmonics and their causes are identified. The measured harmonic spectra are finally used in a sensorless control scheme in order to improve the position estimation for the investigated machine showing multiple saliencies.