Abstract: A transformer arrangement comprising a transformer having a primary side for receiving input voltage and current from a source and a secondary side for providing output voltage and current to a load. The transformer arrangement further comprises an AC-AC PE converter connected to a thyristor used for bypassing the AC-AC PE converter in case of a short-circuit fault in a terminal of the primary side and/or the secondary side. The transformer arrangement further comprises a thyristor-based AC-AC PE converter connected to a thyristor-tapped winding. The AC-AC PE converter is connected with the thyristor-tapped winding via the thyristor-based AC-AC PE converter. The thyristor-based AC-AC PE converter is connected to an impedance to protect the thyristor-tapped winding from short-circuit faults of the thyristor-based AC-AC PE converter.

Abstract: A method for controlling an output voltage of at least one transformer in a power grid comprises providing the one transformer(s) with a power electronics converter and an output voltage controller, determining a grid frequency, comparing the grid frequency with a reference value, producing an error signal, applying the error signal as feedback to the controller, and generating a control action to cause the controller to change the output voltage of the transformer comprising a power electronics converter. The power electronics converter is an AC-AC converter, and the method comprises connecting the AC-AC converter to either a primary side or a secondary side of the transformer. The AC-AC converter has a first AC side and a second AC side and the method comprises connecting two terminals on the first AC side to a winding of the transformer, and connecting the second AC side to an external circuit line.

Abstract: A transformer arrangement comprising a transformer having a primary side for receiving input voltage and current from a source and a secondary side for providing output voltage and current to a load. The transformer arrangement further comprises an AC-AC PE converter connected to a thyristor used for bypassing the AC-AC PE converter in case of a short-circuit fault in a terminal of the primary side and/or the secondary side. The transformer arrangement further comprises a thyristor-based AC-AC PE converter connected to a thyristor-tapped winding. The AC-AC PE converter is connected with the thyristor-tapped winding via the thyristor-based AC-AC PE converter. The thyristor-based AC-AC PE converter is connected to an impedance to protect the thyristor-tapped winding from short-circuit faults of the thyristor-based AC-AC PE converter.

Abstract: A method for controlling an output voltage of at least one transformer in a power grid. The comprises providing the least one transformers with a power electronics converter and an output voltage controller, determining a grid frequency, comparing the grid frequency with a reference value, producing an error signal, applying the error signal as feedback to the controller, and generating a control action to cause the controller to change the output voltage of the transformer comprising a power electronics converter. The power electronics converter is an AC-AC converter, and the method comprises connecting the AC-AC converter to either a primary side or a secondary side of the transformer. The AC-AC converter has a first AC side and a second AC side and the method comprises connecting two terminals on the first AC side in-parallel to a winding of the transformer, and connecting the second AC side to an external circuit line.

Abstract: A charging system for an automated guided vehicle, AGV, is presented. The charging system includes an offboard, meshed charging grid and onboard contact pads. The offboard, meshed charging grid including a charging pole in each grid point, wherein adjacent charging poles are configured with opposite polarity of a charging current. The onboard contact pads include four separate contact pads. An AGV is also presented.

Abstract: A transformer arrangement includes a first and a second arrangement side and a transformer with first windings coupled to the first arrangement side and with second windings having a first to a fourth tap. The transformer arrangement comprises a converter coupling the first, second and third tap to the second arrangement side, a first filter circuit coupling the first tap to the third tap and a second filter circuit coupling the third tap to the second tap.

Abstract: A solar power plant including a power conversion system and a method of controlling the power conversion system. Implemented in a DC/AC inverter, the plant includes photovoltaic modules (PV modules) arranged in arrays connected to a respective DC/DC converters. A power collecting grid interfaces between the DC/DC converters and the DC/AC inverter. The method includes monitoring the performance of each PV array by adjusting the voltage level of each interface between a PV array and the corresponding DC/DC converter, and includes monitoring the output power of each DC/DC converter as a feedback for the regulating.

Abstract: A power system includes a power generating plant including a plurality of power generators, and an AC collection grid adapted to interconnect the power generating plant and an HVDC converter station. The AC collection grid is adapted to operate outside network regulations, whereby advantages such as simplified control and electronics are achieved. A method of operating a power system is also provided.

Abstract: A solar power plant including a power conversion system and a method of controlling the power conversion system. Implemented in a DC/AC inverter, the plant includes photovoltaic modules (PV modules) arranged in arrays connected to a respective DC/DC converters. A power collecting grid interfaces between the DC/DC converters and the DC/AC inverter. The method includes monitoring the performance of each PV array by adjusting the voltage level of each interface between a PV array and the corresponding DC/DC converter, and includes monitoring the output power of each DC/DC converter as a feedback for the regulating.

Abstract: A power system includes a power generating plant including a plurality of power generators, and an AC collection grid adapted to interconnect the power generating plant and an HVDC converter station. The AC collection grid is adapted to operate outside network regulations, whereby advantages such as simplified control and electronics are achieved. A method of operating a power system is also provided.

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 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.