AC-DC Converter Minimizing Induced Harmonics in Industrial Power Systems

Conventional ac-dc converters present two important disadvantages: they create harmonic currents and require reactive power. To reduce these drawbacks, a diode rectifier is directly connected in series with a chopper controlled by pulsewidth modulation. Both are preceded by a series inductance (added to the equivalent one of the power system) and a shunt capacitor. This study is applied to single-phase powerful electric locomotives. Equivalent three-phase systems are not so interesting.