Abstract: Embodiments for a voltage source converter are disclosed.

Abstract: A high frequency high power converter system comprises: a plurality of resonant tank circuits arranged in parallel, a plurality of transformers, each transformer having a single primary winding and a plurality of secondary windings, and a vacuum electronic device, the output of each resonant tank circuit being applied to a respective different transformer and the outputs of the transformers being arranged to drive the vacuum electronic device.

Abstract: A voltage source converter comprises first and second DC terminals for connection to a DC network, and at least one limb connected between the first and second DC terminals. The or each limb includes: a phase element including two parallel-connected sets of series-connected switching elements connected in an H-bridge to define first and second diagonal switching pairs, a respective junction between each set of series-connected switching elements defining an AC terminal for connection to an AC network; and a sub-converter configured to be controllable to act as a voltage waveform synthesizer. The voltage source converter further includes a controller to operate the sub-converter to selectively synthesize a driving commutation voltage to modify a DC side current at a DC side of the H-bridge to minimize any differences in magnitude and direction between the DC side current and an AC side current at an AC side of the H-bridge.

Abstract: A voltage source converter comprises first and second DC terminals for connection to a DC network, and at least one limb connected between the first and second DC terminals. The or each limb includes: a phase element including two parallel-connected sets of series-connected switching elements connected in an H-bridge to define first and second diagonal switching pairs, a respective junction between each set of series-connected switching elements defining an AC terminal for connection to an AC network; and a sub-converter configured to be controllable to act as a voltage waveform synthesizer. The voltage source converter further includes a controller to operate the sub-converter to selectively synthesize a driving commutation voltage to modify a DC side current at a DC side of the H-bridge to minimize any differences in magnitude and direction between the DC side current and an AC side current at an AC side of the H-bridge.

Abstract: A voltage source converter is used in high voltage direct current power transmission and reactive power compensation. The voltage source converter includes first and second DC terminals for connection in use to a DC network, three phase elements and at least one auxiliary converter connected between the first and second DC terminals, each phase element including a plurality of primary switching elements and at least one AC terminal for connection in use to a respective phase of a multi-phase AC network, the plurality of primary switching elements being controllable in use to facilitate power conversion between the AC and DC networks, the or each auxiliary converter being operable in use to act as a waveform synthesizer to modify a first DC voltage presented to the DC network so as to minimize ripple in the DC voltage.

Abstract: A voltage source converter is used in high voltage direct current power transmission and reactive power compensation. The voltage source converter comprises first and second DC terminals for connection in use to a DC network, three phase elements and at least one auxiliary converter connected between the first and second DC terminals, each phase element including a plurality of primary switching elements and at least one AC terminal for connection in use to a respective phase of a multi-phase AC network, the plurality of primary switching elements being controllable in use to facilitate power conversion between the AC and DC networks, the or each auxiliary converter being operable in use to act as a waveform synthesizer to modify a first DC voltage presented to the DC network so as to minimise ripple in the DC voltage.