A multiple PWM GTO line-side converter for unity power factor and reduced harmonics

A multiple PWM GTO line-side converter with low switched frequency has been developed for industrial uses needing both higher capacity and performance. The multiple converter is composed of two GTO converter units parallel connected through an interphase reactor. The switching frequency of the GTO thyristors in the multiple converter can be reduced to a quarter of that in the single converter. It is verified by simulations and experiments with a 2750 kVA GTO converter and inverter system with 500 Hz switching frequency that the system has: (1) a unity power factor, (2) reduced harmonics, (3) bidirectional power flow, and (4) speed regulatory performance equal to that of an advanced cycloconverter drive system.<
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