Sensorless starting control for a brushless DC motor

摘要: A sensorless control system for reliably starting a brushless DC motor even when the motor/load inertia is relatively high and though rotor may be rotating in wrong direction initiated. The line-to-line generated voltages of two deenergized stator windings are compared as given winding energized. energization either interrupted or permitting to continue depending on comparison. If comparison indicates that turning correct direction, continued produce synchronous positive torque accelerating direction. voltage interrupted, next sequential interruption occurs alternate sequence, effectively reversing sequence generate substantially maximum braking bringing stop, whereafter attempted again.