Abstract: The present invention discloses a power conversion system and a method for pre-charging DC-Bus capacitors therein. The power conversion system comprises a plurality of power modules, each including a power input end; a charging input end; a power output end; at least one power conversion unit, each of the power conversion unit including at least one DC-Bus capacitor and being electrically connected to the power input end and the power output end; and a pre-charging unit electrically connected to the charging input end for receiving direct current and electrically connected to the DC-Bus capacitor for pre-charging the DC-Bus capacitor. The power input ends of the plurality of power modules are connected in series and then electrically connected to an AC power source, and the power output ends of the plurality of power modules are connected in parallel.

Abstract: The present invention discloses a power conversion system and a method for pre-charging DC-Bus capacitors therein. The power conversion system comprises a plurality of power modules, each including a power input end; a charging input end; a power output end; at least one power conversion unit, each of the power conversion unit including at least one DC-Bus capacitor and being electrically connected to the power input end and the power output end; and a pre-charging unit electrically connected to the charging input end for receiving direct current and electrically connected to the DC-Bus capacitor for pre-charging the DC-Bus capacitor. The power input ends of the plurality of power modules are connected in series and then electrically connected to an AC power source, and the power output ends of the plurality of power modules are connected in parallel.

Abstract: A multiunit power conversion system comprises: a first power conversion unit, a second power conversion unit, and a current sharing transformer. The first power conversion unit comprises a first resonant capacitor and a first resonant inductor in series. The second power conversion unit comprises a second resonant capacitor and a second resonant inductor in series. The current sharing transformer comprises a first winding and a second winding magnetically coupled for current-sharing of the first and second power conversion units. The first and second windings are connected in parallel to the first and second resonant capacitors, respectively; or the first and second windings are connected in parallel to the first and second resonant inductors, respectively; or the first winding is connected in parallel to the first resonant capacitor and the first resonant inductor, and the second winding is connected in parallel to the second resonant capacitor and the second resonant inductor.

Abstract: A multiunit power conversion system comprises: a first power conversion unit, a second power conversion unit, and a current sharing transformer. The first power conversion unit comprises a first resonant capacitor and a first resonant inductor in series. The second power conversion unit comprises a second resonant capacitor and a second resonant inductor in series. The current sharing transformer comprises a first winding and a second winding magnetically coupled for current-sharing of the first and second power conversion units. The first and second windings are connected in parallel to the first and second resonant capacitors, respectively; or the first and second windings are connected in parallel to the first and second resonant inductors, respectively; or the first winding is connected in parallel to the first resonant capacitor and the first resonant inductor, and the second winding is connected in parallel to the second resonant capacitor and the second resonant inductor.