Abstract: Pump station motor has small load torque when speed is slow, not wide range of speed regulation and non-frequent starting and braking. In view of this, a doubly-fed coiling motor speed regulation system based on dual-PWM (Pulse Width Modulation) control is presented. Dual-close-loop i.e. current inner loop and voltage outer loop control is used in the rectifier, and selected speed and flux dual-close-loop vector control strategy in generator-side converter. The obtained experimental results indicate that dual-PWM converter could achieve bidirectional energy streaming. The presented system has high control precision, quick dynamic response, and little harmonic pollution. It could also adjust the motor speed smoothly at the state of sub-synchronous or hyper-synchronous running, improve speed regulation performance of pump station motor and has obvious energy-saving effect.

Key words: doubly-fed speed regulation, vector control, PWM converter, spatial vector pulse width modulation, pump station motor