Robust startup control of sensorless PMSM drives with self-commissioning

This paper presents a robust sensorless startup control method with self-commissioning for permanent magnet motors for smooth ramping speed up without reversing oscillations. Low cost sinusoidal PMSM motors used for fan and blower applications may have large parameter variations and static friction uncertainties. A reliable startup control with smooth operation thus becomes an indispensable requirement for practical applications. A self-commissioning strategy is developed to identify the fan motor parameters when a new application is initiated. These identified parameters are stored in an EEPROM and are used for the field oriented sensorless control of the of the PMSM motor drive. Based on the identified motor parameters, a start-up scheme will apply a series of voltage pulses with proper time durations to each stator winding and the corresponding peak currents are measured for the detection of initial commutation state of the rotor. The proposed scheme will not cause visible rotor vibrations and audio noises during the detection process. The sensorless startup with self-commissioning scheme has been implemented based on a single-chip MCU controller (STM32F0). Experimental results reveal that the proposed scheme can achieve reliable and smooth startup with robust performances.