Abstract: An electrical system forming part of a solar power plant is described. The electrical system includes a plurality of photovoltaic (PV) panels, a power converter, and a controller. In response to a detected electric arc on the DC side of the power converter, the controller is configured to enable a short circuit state of the power converter by controlling semiconductor switches of the power converter (e.g., turning on some or all of the semiconductor switches) to create a short circuit between DC input terminals of the power converter. The short circuit path though the power converter will extinguish the detected electric arc in the connected DC circuit.

Abstract: An electrical system forming part of a solar power plant is described. The electrical system includes a plurality of photovoltaic (PV) panels, a power converter, and a controller. In response to a detected electric arc on the DC side of the power converter, the controller is configured to enable a short circuit state of the power converter by controlling semiconductor switches of the power converter (e.g., turning on some or all of the semiconductor switches) to create a short circuit between DC input terminals of the power converter. The short circuit path though the power converter will extinguish the detected electric arc in the connected DC circuit.

Abstract: A power converter system is described. The system includes a power converter with a first converter including a plurality of semiconductor devices. Each semiconductor device includes at least a controllable semiconductor switch having a threshold voltage and a gate voltage for normal on-state conduction. The first converter has first and second DC terminals connected to a DC circuit, and a plurality of AC terminals. A controller is configured to supply current to the first converter (e.g., from an AC power source) and enable a short circuit state of the first converter by controlling semiconductor switches of the first converter to create at least one short circuit path through the first converter that carries the supplied current. At least one of the semiconductor switches in at least one of the short circuit paths is operated with modified on-state conduction in order to increase conduction losses.

Abstract: A method of short-circuiting a faulty submodule for a voltage-source power converter is disclosed. The submodule is based on a full-bridge, asymmetric full-bridge or half-bridge circuit design having power semiconductor switches with anti-parallel freewheeling diodes and optionally non-controllable semiconductor valves. The method 36 includes identifying a faulty semiconductor device and determining a failure mode selected from a short-circuit failure mode and an open circuit failure mode. The method further includes selecting a minimum number of power semiconductor switches suitable to provide a bypass path through the submodule depending on the identified faulty semiconductor device and the determined failure mode and driving the selected power semiconductor switches by a modified driving voltage compared to normal operation to cause them to break down in order to provide a durable, stable, low impedance short-circuit path between the AC voltage terminals of the submodule.

Abstract: A method (36) of short-circuiting a faulty submodule (12, 12?, 12?) for a voltage-source power converter (8) is disclosed. The submodule (12, 12?, 12?) is based on a full-bridge, asymmetric full-bridge or half-bridge circuit design having power semiconductor switches (T1-T4) with anti-parallel freewheeling diodes (D1-D4) and optionally non-controllable semiconductor valves (D1?-D4?). The method 36 includes identifying a faulty semiconductor device and determining a failure mode selected from a short-circuit failure mode and an open circuit failure mode.

Abstract: An inverter system is described. The inverter system includes a DC power source such as a plurality of photovoltaic (PV) panels, an inverter and a controller. The inverter includes a plurality of semiconductor devices (e.g., controllable semiconductor switches such as IGBTs and anti-parallel connected diodes) arranged in a suitable inverter topology. The inverter includes DC input terminals connected to the PV panels by means of a DC link and at least one AC output terminal. When starting the inverter, the controller is configured to enable a short circuit state of the inverter by controlling the semiconductor switches to create a short circuit between the DC input terminals such that the inverter carries a current substantially equal to the short circuit current of the PV panels.

Abstract: An inverter system (1) is described. The inverter system (1) includes a DC power source such as a plurality of photovoltaic (PV) panels (8), an inverter (2) and a controller (32). The inverter (2) includes a plurality of semiconductor devices (e.g., controllable semiconductor switches such as IGBTs and anti-parallel connected diodes) arranged in a suitable inverter topology. The inverter (2) includes DC input terminals (4) connected to the PV panels (8) by means of a DC link (10) and at least one AC output terminal (6). When starting the inverter (2), the controller (32) is configured to enable a short circuit state of the inverter (2) by controlling the semiconductor switches to create a short circuit between the DC input terminals (4) such that the inverter (2) carries a current substantially equal to the short circuit current of the PV panels (8).

Abstract: A method and a device for controlling a commutation process of a load current between two switching modules are disclosed that each have a MOSFET that can be controlled by a gate-source voltage, and an intrinsic-body inverse diode. To reduce oscillations in the down-commutation of the inverse diodes caused by parasitic circuit parameters, after switching off one of the switching modules, the gate-source control voltage applied to this switching module is temporarily switched off until being increased again the vicinity of the threshold voltage for switching on the MOSFET, before and while the other switching module is switched on, in order to commutate the current from the inverse diode of the one switching module to the MOSFET of the other switching module.

Abstract: A method and a device for controlling a commutation process of a load current between two switching modules are disclosed that each have a MOSFET that can be controlled by a gate-source voltage, and an intrinsic-body inverse diode. To reduce oscillations in the down-commutation of the inverse diodes caused by parasitic circuit parameters, after switching off one of the switching modules, the gate-source control voltage applied to this switching module is temporarily switched off until being increased again the vicinity of the threshold voltage for switching on the MOSFET, before and while the other switching module is switched on, in order to commutate the current from the inverse diode of the one switching module to the MOSFET of the other switching module.