Article

A new slip power recovery scheme with improved supply power factor

Dept. of Electr. Eng., Indian Inst. of Technol., Kanpur
IEEE Transactions on Power Electronics (Impact Factor: 5.73). 05/1988; DOI: 10.1109/63.4350
Source: IEEE Xplore

ABSTRACT A slip power recovery scheme with a PWM (pulsewidth-modulation)
converter in the rotor circuit is investigated. The steady-state
performance characteristics, such as speed-torque characteristics and
the overall power factor of the drive system, are determined using
simple DC and AC equivalent circuits. The performance characteristics
are verified experimentally, showing good agreement with theoretical
results. The power factor of the drive system is improved significantly
over the entire range of speed control. The drive provides speed-torque
characteristics similar to those of a separately excited DC motor.
Oscillograms of typical waveforms from the experimental set-up are
illustrated to demonstrate the satisfactory performance of the scheme

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