Abstract: There is provided a method of controlling a plurality of converter cells in a phase arm of a modular multilevel converter (MMC) in accordance with a main reference. The method includes dividing the main reference into a plurality of reference parts, and, by using a grouping of the plurality of converter cells into a plurality of groups, operating a plurality of modulators in parallel, each modulator controlling a respective one of the groups of converter cells in accordance with one of the reference parts. A phase arm controlled in accordance with such a method is also provided, as well as an MMC including at least one such phase arm, and a converter station including at least one such MMC.

Abstract: A method for establishing a wireless communication system in a high-voltage power converter station is provided. The high-voltage power converter station includes a plurality of power devices. The wireless communication system includes a plurality of wireless communication devices, some of which are associated with a power device such that a power device and a wireless communication device together form a wireless power electronic module. The high-voltage power converter station further comprises at least one wireless networking device for providing a communication interface between the plurality of wireless communication devices and a controller configured to control the power devices.

Abstract: There is provided a method of controlling a plurality of converter cells in a phase arm of a modular multilevel converter (MMC) in accordance with a main reference. The method includes dividing the main reference into a plurality of reference parts, and, by using a grouping of the plurality of converter cells into a plurality of groups, operating a plurality of modulators in parallel, each modulator controlling a respective one of the groups of converter cells in accordance with one of the reference parts. A phase arm controlled in accordance with such a method is also provided, as well as an MMC including at least one such phase arm, and a converter station including at least one such MMC.

Abstract: A high voltage valve arrangement includes a high voltage valve unit; an external electric shield structure arranged at least partially around the high voltage modular valve unit and a grounding system. The grounding system includes a grounding system configured to be remotely extended from a retracted position to an extended position, whereby the extendable grounding device establishes electric connection with the external shield structure when it is extended from the retracted position.

Abstract: A method for controlling a first and a second reverse-conducting insulated gate bipolar transistor (RC-IGBT), electrically connected in series, is disclosed. A collector of the first RC-IGBT is electrically connected to a positive pole of a direct current voltage source, and an emitter of the second RC-IGBT is electrically connected to a negative pole of the DC voltage source. Further, an emitter of the first RC-IGBT is electrically connected to a collector of the second RC-IGBT to form an alternating current terminal. A gate voltage is applied to respective gates of the first and second RC-IGBTs, wherein the gate voltage is controlled based on a magnitude and a direction of an output current on the AC terminal and on a command signal alternating between a first and a second value.

Abstract: A short-circuiting arrangement for capacitors of a high voltage converter are provided, the capacitors each having two connection terminals, the arrangement including a short-circuiting wire configured to be moved along while in sliding contact with the connection terminals and including a short-circuiting section with electrically conductive material connected to a ground potential and a probing section with electrically conductive material and a voltage evaluating unit electrically connected to the short-circuit section and the probing section and configured to detect, as the probing section and short-circuiting section are connected to the respective connection terminals, the voltage across the capacitor, compare the voltage with a discharge threshold and halt or move the short-circuiting wire based on the detected voltage.

Abstract: It is provided a mechanical bypass switch device arranged to bypass a converter cell in a power converter. The mechanical bypass switch device includes: a mechanical switch; a mechanical switch actuator arranged to make the mechanical switch conduct when supplied with an electric signal; a first control input; and a second control input. The mechanical bypass switch device is arranged such that a control signal, provided on either one of the first control input and the second control input or on both of the first control input and the second control input, causes the mechanical switch to conduct. A corresponding converter arm and bypass converter are also presented.

Abstract: A high voltage valve arrangement includes a high voltage valve unit; an external electric shield structure arranged at least partially around the high voltage modular valve unit and a grounding system. The grounding system includes a grounding system configured to be remotely extended from a retracted position to an extended position, whereby the extendable grounding device establishes electric connection with the external shield structure when it is extended from the retracted position.

Abstract: It is provided a mechanical bypass switch device arranged to bypass a converter cell in a power converter. The mechanical bypass switch device includes: a mechanical switch; a mechanical switch actuator arranged to make the mechanical switch conduct when supplied with an electric signal; a first control input; and a second control input. The mechanical bypass switch device is arranged such that a control signal, provided on either one of the first control input and the second control input or on both of the first control input and the second control input, causes the mechanical switch to conduct. A corresponding converter arm and bypass converter are also presented.

Abstract: A short-circuiting arrangement for capacitors of a high voltage converter are provided, the capacitors each having two connection terminals, the arrangement including a short-circuiting wire configured to be moved along while in sliding contact with the connection terminals and including a short-circuiting section with electrically conductive material connected to a ground potential and a probing section with electrically conductive material and a voltage evaluating unit electrically connected to the short-circuit section and the probing section and configured to detect, as the probing section and short-circuiting section are connected to the respective connection terminals, the voltage across the capacitor, compare the voltage with a discharge threshold and halt or move the short-circuiting wire based on the detected voltage.

Abstract: A method for controlling a first and a second reverse-conducting insulated gate bipolar transistor (RC-IGBT), electrically connected in series, is disclosed. A collector of the first RC-IGBT is electrically connected to a positive pole of a direct current voltage source, and an emitter of the second RC-IGBT is electrically connected to a negative pole of the DC voltage source. Further, an emitter of the first RC-IGBT is electrically connected to a collector of the second RC-IGBT to form an alternating current terminal. A gate voltage is applied to respective gates of the first and second RC-IGBTs, wherein the gate voltage is controlled based on a magnitude and a direction of an output current on the AC terminal and on a command signal alternating between a first and a second value.