Sensorless Field Oriented Control of PMSM using Direct Flux Control with improved measurement sequence

Abstract

In this paper sensorless Field Oriented Control (FOC) of a Permanent Magnet Synchronous Machine (PMSM) is realized using the Direct Flux Control (DFC) sensorless method. In contrast with previous work, the DFC variant implemented in this paper uses an improved measurement sequence that extract the flux linkage signals needed by DFC to estimate the rotor position with the same offset level. Furthermore, based on FOC and the improved DFC, a closed speed loop is designed and tested in a simulation environment. The simulation environment uses a high fidelity Finite Element (FE) model of a PMSM that was designed in ANSYS Maxwell. The FE model is coupled with a power electronic circuit model and the control algorithm implemented in ANSYS Simplorer. Calculation of the rotor speed based on the information delivered by the DFC method is also covered. Finally, the simulation results of the speed close loop with DFC and the improved measurement sequence are presented and discussed.