A Direct Flux Observer Based on a Fast Resettable Integrator Circuitry for Sensorless Control of PMSMs

The Direct Flux Observer technique for sensorless control of PMSMs (permanent magnet synchronous motors) allows obtaining a measurement of the ratios of the flux linkages of the motor phases, which are functions of the electrical rotor position needed for motor driving. These measured signals are affected by noise and the ringing generated by the three-phase inverter etc. Therefore, an analog fast resettable integrator circuitry is used in order to enhance the signal quality by a specific integration procedure of the measured signals. The performance of the proposed circuitry has been tested on two different motors. Experimental results are shown and discussed.