New reliable sensorless startup strategy of brushless DC motor for large inertia system

A new reliable sensorless startup strategy of brushless DC (BLDC) motor is proposed to prevent long time integration commutation error specialized for large inertia load and to adapt large disturbance torque fluctuation. It includes four segments: orientation segment, I/f startup segment, observer startup segment and back EMF startup segment. Experimental results show that the proposed method could better adapt to large inertia systems with large disturbance torque fluctuation comparing with conventional methods.