Abstract: A gate control circuit including: a gate input arranged to receive an input gate feed signal; a gate output arranged to be connected, during normal operation, to at least one switching module for controlling current through a main circuit, the gate output being connected to the gate input; a power supply; and a switch connected between the power supply and the gate output, the switch being arranged to close as a response to a failure. A corresponding power module and method are also presented.

Abstract: A Voltage Source Converter having at least one phase leg connected to opposite poles of a direct voltage side of the converter and including a series connection of switching cells has an arrangement configured to apply a pressure to opposite ends of stacks of semiconductor assemblies for pressing the assemblies towards each other so as to obtain electric contact between semiconductor assemblies in the stack while ensuring that the semiconductor assemblies of a first path of each switching cell of the converter go into a permanently closed circuit state in case of a failure of the respective switching cell. A second path of each switching cell has a member configured to keep the second path including an energy storing capacitor non-conducting upon occurrence of the failure.

Abstract: A converter building including at least one room having a solid room wall enclosing an interior space and an electrical active part contained in the interior space, the room wall having at least one opening, which is designed such that it allows a human to enter the interior space. The opening is sealable, the room wall encloses the interior space in a gas-tight manner when the opening is sealed, and the interior space contains a dielectric insulation medium including a dielectric insulation component other than air.

Abstract: A device for converting a DC voltage into an AC voltage includes a passive electronic filter having a first and second energy storage element, a third energy storage element placed between the first and second energy storage elements, a fourth energy storage element connected between a junction of the first energy storage element and the third energy storage element and an AC terminal and a fifth energy storage element connected between a junction of the second energy storage element and the third energy storage element and the AC terminal. The energy storage elements are of two different types, capacitive and inductive, with values selected to provide reduction of frequency components at two times the fundamental frequency of the AC voltage and at three times the fundamental frequency of the AC voltage.

Abstract: Voltage source converter based on a chain-link cell topology including one or more phases, each of the phases having one or more series-connected chain-link cell modules connected to each other. The output voltage of the voltage source converter is controlled by control signals applied to the series-connected chain-link cell modules. In case of failure of a chain-link cell module, that module is controlled, by the control signals, such that zero output voltage is provided at its output voltage AC terminal.

Abstract: A DC/DC converter including a first conversion branch stretching between a first and a second DC terminal, a first controllable voltage source in a first half of the first conversion branch, a second controllable voltage source in a second half of the first conversion branch, a conversion unit converting between AC and DC and at one end connected to a third and a fourth DC terminal, and a transformer with a primary winding connected in a first interconnecting branch stretching between a first junction at which the first and second controllable voltage sources are connected to each other and a first potential that lies in the middle between the potentials of the first and second DC terminal, and a secondary winding connected to another end of the conversion unit.

Abstract: The present invention relates to an AC/DC converter comprising at least two phase legs connected in series between first and second DC connection terminals of the AC/DC converter, wherein each phase leg comprises: an AC connection having first and second terminals arranged to connect the phase leg to a phase of an AC system; a phase branch comprising at least one converter cell and having first and second branch end terminals; and a capacitor. The capacitor is connected the between the first branch end terminal and the first AC connection terminal, so that the capacitor forms a DC blocking capacitor. The second AC terminal is connected to the second branch end terminal. The series connection of the phase legs between first and second DC connection terminal is such that a first series connection point in a phase leg is located between the first branch end terminal and the capacitor, while a second series connection point is located between the second branch end terminal and the second AC connection.

Abstract: A cascaded electric power converter and a method of operating a cascaded electric power converter are disclosed. The cascaded converter includes: a converter cell including a cell capacitor and at least one phase leg having at least two electric valves, the at least one phase leg being connected in parallel to the cell capacitor; and a control system for controlling the switching of the electric valves of the at least one phase leg. The control system is configured to, upon detection of a need to by-pass the converter cell, control the switching of the electric valves in a manner so that the cell capacitor is short circuited via a phase leg, so as to obtain a current surge through the phase leg, thereby creating a permanent current path through the converter cell.

Abstract: A device for converting a DC voltage into an AC voltage includes a passive electronic filter having a first and second energy storage element, a third energy storage element placed between the first and second energy storage elements, a fourth energy storage element connected between a junction of the first energy storage element and the third energy storage element and an AC terminal and a fifth energy storage element connected between a junction of the second energy storage element and the third energy storage element and the AC terminal. The energy storage elements are of two different types, capacitive and inductive, with values selected to provide reduction of frequency components at two times the fundamental frequency of the AC voltage and at three times the fundamental frequency of the AC voltage.

Abstract: The present invention relates to an AC/DC converter station for interconnection of a DC transmission line and an AC network, the AC/DC converter station including an AC/DC converter and a control system configured to control the AC/DC converter. The AC/DC converter station comprises a capacitor connected in series between the AC/DC converter and the AC network, and a voltage measurement device arranged to measure the voltage across the capacitor. The AC/DC converter further comprises a control system connected to the voltage measurement device and arranged to receive, from the voltage measurement device, a signal indicative of a measured voltage. The control system is arranged to perform the control of the AC/DC converter in dependence of the signal received from the voltage measurement device. The invention further relates to a method of operating an AC/DC converter station.

Abstract: A method, voltage source converter and computer program product for limiting the current in a DC power transmission system are disclosed. The voltage source converter has an AC side and a DC side and a fault current path between these sides. It furthermore includes a control unit and at least one switching unit of a first type provided in the fault current path and that includes a primary switching element together with an anti-parallel secondary controllable rectifying element. Based on a fault being detected in the DC power system when the primary switching elements of the converter are blocked, the control unit changes the control of the controllable rectifying element from acting as a non-controllable rectifying to acting as a controllable rectifying element.

Abstract: The invention concerns a voltage source converter (26) comprising a group of phase legs, at least three connection terminals (AC1, AC2, AC3, DC+, DC?) for connecting the phase legs to power transmission elements, a first group of cells (C1p1, C2p1, C1n1, C2n1, C1p2, C2p2, C1n2, C2n2, C1p3, C2p3, C1n3, C2n3) in each phase leg and a second group of cells (C3p1, C3n1, C3p2, C3n2 C3p3, C3n3). The cells (C1p1, C2p1, C1n1, C2n1, C1p2, C2p2, C1n2, C2n2, C1p3, C2p3, C1n3, C2n3) in the first group are only capable of providing unipolar voltage contributions to the converter and connected for only being capable of such unipolar voltage contributions, while the cells (C3p1, C3n1, C3p2, C3n2 C3p3, C3n3) in the second group are connected to the corresponding cells of the first group and arranged to have bipolar voltage contribution capability.

Abstract: An arrangement to determine a cell capacitor voltage value of a cell of a multi-cell power converter includes the cell and a control unit. The cell itself includes four power electronic valves interconnected as a full-bridge converter having a first and a second phase leg, where each phase leg includes a series-connection of two of the four power electronic valves and where the connection point between the two power electronic valves of each phase leg is externally connectable, a cell capacitor being connected in parallel to the first and the second phase legs, and four gate units, each being connected to a corresponding one of the power electronic valves as well as to the control unit.

Abstract: Power exchanging arrangement, in shunt connection, with a three-phase electric power network including on one hand for each said phase a reactive impedance element and a Voltage Source Converter connected in series with said element, and on the other hand a control unit configured to control semiconductor devices of turn-off type of said converter for generating a voltage with a fundamental frequency being equal to the fundamental frequency of the voltage of the respective said phase and by that control a flow of reactive power between said arrangement and the respective phase of said electric power network. Each Voltage Source Converter includes a series connection of switching cells in the form of so-called H-bridges including two switching elements connected in parallel and each having at least two semiconductor assemblies connected in series. Each switching cell further comprises at least one energy storing capacitor connected in parallel with said switching elements.

Abstract: Voltage source converter based on a chain-link cell topology including one or more phases, each of the phases having one or more series-connected chain-link cell modules connected to each other. The output voltage of the voltage source converter is controlled by control signals applied to the series-connected chain-link cell modules. In case of failure of a chain-link cell module, that module is controlled, by the control signals, such that zero output voltage is provided at its output voltage AC terminal.

Abstract: An arrangement to determine a cell capacitor voltage value of a cell of a multi-cell power converter includes the cell and a control unit. The cell itself includes four power electronic valves interconnected as a full-bridge converter having a first and a second phase leg, where each phase leg includes a series-connection of two of the four power electronic valves and where the connection point between the two power electronic valves of each phase leg is externally connectable, a cell capacitor being connected in parallel to the first and the second phase legs, and four gate units, each being connected to a corresponding one of the power electronic valves as well as to the control unit.

Abstract: A photovoltaic system for generating an output voltage that is uninfluenced by varying irradiation, includes a photovoltaic source having an input terminal and an output terminal. The photovoltaic system includes a voltage adding arrangement having a first input terminal and an output terminal. The voltage adding arrangement is connected in series with the photovoltaic source, and includes a first route having a voltage source and a second route as a voltage source bypass. The first and second routes extend between the first input terminal and the output terminal of the voltage adding arrangement. The first and second routes being alternately activateable.

Abstract: A Voltage Source Converter having at least one phase leg connected to opposite poles of a direct voltage side of the converter and comprising a series connection of switching cells has an arrangement configured to apply a pressure to opposite ends of stacks of semiconductor assemblies for pressing the assemblies towards each other so as to obtain electric contact between semiconductor assemblies in said stack while ensuring that the semiconductor assemblies of a first path of each switching cell of the converter go into a permanently closed circuit state in case of a failure of the respective switching cell. A second path of each switching cell has means configured to keep said second path including an energy storing capacitor non-conducting upon occurrence of a said failure.

Abstract: The invention relates to a converter provided with a resonant circuit (16), which comprises a control device (24) adapted, in connection with a commutation of the phase current (iph) from a semiconductor element of turn-off type of a first current valve (2, 3) to a rectifying member of a second current valve (3, 2) to effectuate a turn-on of the auxiliary valve (18) of the resonant circuit with a varaible time delay (td) after the turn-off of the first current valve, the converter comprising a member (35) for determining said time delay in dependence on the magnitude and the direction of the phase current (iph) and the magnitude and the direction of a determined unbalance so that the unbalance is corrected at least partly when the control device applies the time delay (td). The invention also relates to a method for controlling such a converter.

Abstract: The invention relates to a VSC-converter for converting direct voltage into auxiliary voltage and vice versa, which comprises a series connection of at least two current valves (5, 6) arranged between two poles (7, 8), a positive and a negative, of a direct voltage side of the converter, each current valve comprising several series connected circuits (12), each of which circuits comprising a semiconductor component (13) of turn-off type and a rectifying component (14) connected in anti-parallel therewith, an alternating voltage phase line (16) being connected to a midpoint (15), denominated phase output, of the series connection of current valves (5, 6) between two of said current valves while dividing the series connection into two equal parts.