摘要 |
A voltage-type self-commutated conversion system including a voltage-type self-commutated power converter with a plurality of anti-parallel circuits of a self-turn-off device and a diode. DC terminals of the power converter are connected to DC bus lines of the voltage-type self-commutated conversion system. The voltage-type self-commutated conversion system further includes a DC capacitor connected between the DC bus lines, a transformer connected between an AC system and AC terminals of the power converter and a control circuit for controlling the power converter. The control circuit includes a gate control circuit for generating gate signals for determining conduction periods of the self-turn-off devices in the power converter, a first protection circuit for turning on the self-turn-off devices connected to positive side of the DC bus line in case of protective shutdown of the power converter and a second protection circuit for turning off the self-turn-off devices connected to negative side of the DC bus line in case of the protective shutdown of the power converter.
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