A method and apparatus for start-up of a voltage source converter (VSC) which is connected to an energized DC link (DC+, DC−). The VSC is connected to a first AC network via a first transformer and an AC isolation switch, the AC isolation switch being coupled between the first transformer and the AC network. The method involves using an auxiliary AC power supply to generate an AC supply to energize the first transformer with the AC isolation switch open. The VSC is then started, with a VSC controller using the AC supply generated by the auxiliary AC power supply as a reference for controlling the VSC. The auxiliary AC power supply may also be used to supply power to at least one VSC load, such as the controller and/or an auxiliary load such as a cooling system. Once the VSC is started the isolation switch 204 can be closed.

A method and apparatus for start-up of a voltage source converter (VSC) which is connected to an energized DC link (DC+, DC−). The VSC is connected to a first AC network via a first transformer and an AC isolation switch, the AC isolation switch being coupled between the first transformer and the AC network. The method involves using an auxiliary AC power supply to generate an AC supply to energize the first transformer with the AC isolation switch open. The VSC is then started, with a VSC controller using the AC supply generated by the auxiliary AC power supply as a reference for controlling the VSC. The auxiliary AC power supply may also be used to supply power to at least one VSC load, such as the controller and/or an auxiliary load such as a cooling system. Once the VSC is started the isolation switch 204 can be closed.

A power sensing and switching circuit, using voltage and current sensors, integrated circuits and logic gates that detects reverse power flow, from reactive loads, non-linear loads or dispersed electrical generators, and mitigates reverse power flow by functioning as a power factor correction device and by diverting the reverse power flow as recycled power to storage, local usage, or remote usage via a recovery line that mitigates distribution grid instability and speeds up the growth of dispersed electrical generators.

A power sensing and switching circuit, using voltage and current sensors, integrated circuits and logic gates that detects reverse power flow, from reactive loads, non-linear loads or dispersed electrical generators, and mitigates reverse power flow by functioning as a power factor correction device and by diverting the reverse power flow as recycled power to storage, local usage, or remote usage via a recovery line that mitigates distribution grid instability and speeds up the growth of dispersed electrical generators.

A power sensing and switching circuit, using voltage and current sensors, integrated circuits and logic gates that detects reverse power flow, from reactive loads, non-linear loads or dispersed electrical generators, and mitigates reverse power flow by functioning as a power factor correction device and by diverting the reverse power flow as recycled power to storage, local usage, or remote usage via a recovery line that mitigates distribution grid instability and speeds up the growth of dispersed electrical generators.

A power sensing and switching circuit, using voltage and current sensors, integrated circuits and logic gates that detects reverse power flow, from reactive loads, non-linear loads or dispersed electrical generators, and mitigates reverse power flow by functioning as a power factor correction device and by diverting the reverse power flow as recycled power to storage, local usage, or remote usage via a recovery line that mitigates distribution grid instability and speeds up the growth of dispersed electrical generators.

A power sensing and switching circuit, using voltage and current sensors, integrated circuits and logic gates that detects reverse power flow, from reactive loads, non-linear loads or dispersed electrical generators, and mitigates reverse power flow by functioning as a power factor correction device and by diverting the reverse power flow as recycled power to storage, local usage, or remote usage via a recovery line that mitigates distribution grid instability and speeds up the growth of dispersed electrical generators.

A power sensing and switching circuit, using voltage and current sensors, integrated circuits and logic gates that detects reverse power flow, from reactive loads, non-linear loads or dispersed electrical generators, and mitigates reverse power flow by functioning as a power factor correction device and by diverting the reverse power flow as recycled power to storage, local usage, or remote usage via a recovery line that mitigates distribution grid instability and speeds up the growth of dispersed electrical generators.

A method and apparatus for start-up of a voltage source converter (VSC) which is connected to an energized DC link (DC+, DC). The VSC is connected to a first AC network via a first transformer and an AC isolation switch, the AC isolation switch being coupled between the first transformer and the AC network. The method involves using an auxiliary AC power supply to generate an AC supply to energize the first transformer with the AC isolation switch open. The VSC is then started, with a VSC controller using the AC supply generated by the auxiliary AC power supply as a reference for controlling the VSC. The auxiliary AC power supply may also be used to supply power to at least one VSC load, such as the controller and/or an auxiliary load such as a cooling system. Once the VSC is started the isolation switch 204 can be closed.

A method and apparatus for start-up of a voltage source converter (VSC) which is connected to an energized DC link (DC+, DC). The VSC is connected to a first AC network via a first transformer and an AC isolation switch, the AC isolation switch being coupled between the first transformer and the AC network. The method involves using an auxiliary AC power supply to generate an AC supply to energize the first transformer with the AC isolation switch open. The VSC is then started, with a VSC controller using the AC supply generated by the auxiliary AC power supply as a reference for controlling the VSC. The auxiliary AC power supply may also be used to supply power to at least one VSC load, such as the controller and/or an auxiliary load such as a cooling system. Once the VSC is started the isolation switch 204 can be closed.