A novel start-up scheme of stator flux oriented vector controlled induction motor drive without torque jerk

The paper proposes a novel zero speed start-up scheme of a stator flux oriented vector-controlled induction motor drive without any torque jerk. A programmable 3-stage low pass filter (LPF) method is used for flux estimation. However, the torque jerk should be generated at the transition due to the time delay of stator flux caused by 3-stage LPF. At standstill condition, a method is derived to calculate a stator flux with only stator current. A feedforward control strategy of the stator flux is suggested to prevent the torque jerk during the transition from standstill mode to the vector control mode. Through experimental results with a 32-bit DSP, the performance of the start-up scheme is verified.