Principle and System Performance of Flexible-Commutation Converter

The traditional line commutated converter has the disadvantages of high harmonic content and high reactive power consumption. So it needs a good deal of filters and reactive power compensation equipement. To deal with this problem of traditional converters, a flexible-commutation converter topology suitable for replacement of traditional line commutated converter is proposed in this paper with its control strategy as well. Then the reactive power and harmonic characteristics of the converter are analyzed. Finally, the electromagnetic transient simulation model is built to validate the excellent performance of the flexible-commutation converter. The simulation results indicate that the AC and DC harmonics of the flexible-commutation converter are greatly reduced compared with the conventional line commutated converter. At the same time, only a little reactive power is consumed when transmitting large capacity active power.