A compact type slip-power recovery system with sinusoidal rotor current for large pump/fan drives

A novel compact type slip-power recovery system having sinusoidal rotor currents is proposed. In the proposed system, a PWM boost rectifier is used as a substitute for a diode rectifier and a boost chopper in a conventional compact type slip-power recovery system. The conventional compact type system has the advantage that the ratings of the inverter and the transformer are only 15% of the motor power capacity. However, a diode rectifier remains in the system. Therefore, it has a rectangular rotor current, and the stator current is distorted. The use of the system proposed in this paper has solved this problem. The effectiveness of the proposed system was verified through computer simulations and experiments.