Hybrid I-f Starting and Observer-Based Sensorless Control of Single-Phase BLDC-PM Motor Drives

A motion sensorless control for single-phase permanent magnet brushless dc motor based on an I-f starting sequence and a real-time permanent magnet flux estimation is proposed here. The special calculation for extracting the position and speed used here implies the generating of an orthogonal flux system, the atan2 trigonometric function, and a phase-locked loop observer. The influence of the permanent magnet flux harmonic content is presented by analytical expressions and digital simulations. The proposed sensorless control is validated by complete experimental results on a commercial small high-speed blower-motor (40 W, 10 krpm, 12 Vdc).