Abstract: A voltage source converter includes a black start control unit and cells, where each cell includes a first switch between a first end of a cell capacitor and a first cell terminal, a second switch between a second end of the cell capacitor and the first cell terminal, where a second cell terminal is provided via the first or the second end of the cell capacitor, a first power supply unit and a second power supply unit, where the black start control unit is configured to perform, after the initial application of a DC voltage to a cell terminal of a cell and the subsequent initial charging of the chargeable power supply unit of one of the switches, charging of an uncharged power supply unit of the other switch through repeatedly turning on and off the switch with initially charged power supply unit.

Abstract: A switching module, intended to be used in a medium or high voltage DC breaker or a DC current limiter, includes at least one power semiconductor switching element, a gate unit arranged to turn the at least one power semiconductor switching element on and off, respectively, according to a switching control signal, and an energy storage capacitor arranged to provide power to a power supply input of the gate unit. The switching module further includes a power transformation device arranged to receive an optical power signal, to transform the optical power signal into an electrical power signal and to provide the electrical power signal to the energy storage capacitor.

Abstract: A gate control device for a semiconductor device includes at least one power supply module, at least one optical communication interface for receiving optical signals from two valve control units and converting them to electric signals for supply to a corresponding power supply module, where in normal operations mode one valve control unit is an active valve control unit and the other is a standby valve control unit, where the optical signal of an active unit energizes the gate control device and provides semiconductor device controlling data, a semiconductor device control module and a reliability control module that performs selection of active valve control unit.

Abstract: A gate control device for a semiconductor device includes at least one power supply module, at least one optical communication interface for receiving optical signals from two valve control units and converting them to electric signals for supply to a corresponding power supply module, where in normal operations mode one valve control unit is an active valve control unit and the other is a standby valve control unit, where the optical signal of an active unit energizes the gate control device and provides semiconductor device controlling data, a semiconductor device control module and a reliability control module that performs selection of active valve control unit.

Abstract: A method and a device to discharge cell capacitors in a cell based voltage source converter. Each cell has switching elements in half bridge or full bridge configuration and a capacitor in parallel to the half or full bridge. Each cell has two terminals, whereof at least one is between two switching elements. The converter has AC and DC terminals, with the possibility to connect each of the terminals to ground, via a further switching element. A resistor is implemented into at least one of the ground connections. To discharge to capacitors, the switching elements in the respective cells are configured such, that the capacitor is in parallel connection to the terminals. The capacitors are thus discharged via the resistor to ground.

Abstract: A method and a device to discharge cell capacitors in a cell based voltage source converter. Each cell has switching elements in half bridge or full bridge configuration and a capacitor in parallel to the half or full bridge. Each cell has two terminals, whereof at least one is between two switching elements. The converter has AC and DC terminals, with the possibility to connect each of the terminals to ground, via a further switching element. A resistor is implemented into at least one of the ground connections. To discharge to capacitors, the switching elements in the respective cells are configured such, that the capacitor is in parallel connection to the terminals. The capacitors are thus discharged via the resistor to ground.

Abstract: A device for converting a DC voltage into an AC voltage and vice versa comprises a control system to control the voltage conversion and at least one phase leg (1) with a first (Uvp1) voltage source connected in series between a first DC terminal (4) and a first AC terminal (6) and with a second (Uvn1) voltage source connected in series between the first AC terminal (6) and a second DC terminal (5). Each of the voltage sources comprises at least a first and a second submodule (15) in series-connection, where each submodule (15) comprises at least two power electronic switches (16) connected in parallel with at least one capacitor (17).

Abstract: A switching module, intended to be used in a medium or high voltage DC breaker or a DC current limiter, includes at least one power semiconductor switching element, a gate unit arranged to turn the at least one power semiconductor switching element on and off, respectively, according to a switching control signal, and an energy storage capacitor arranged to provide power to a power supply input of the gate unit. The switching module further includes a power transformation device arranged to receive an optical power signal, to transform the optical power signal into an electrical power signal and to provide the electrical power signal to the energy storage capacitor.