Abstract: A photovoltaic energy generation system with a string including a series connection of solar modules, which string is electrically connected to an inverter via power lines for converting and feeding electrical power from the string into a network. The inverter is configured to obtain an alternative operating power from only one of the solar modules in the event that normal operating power can be obtained neither from the network nor from the entire string. A supply line can supply the alternative operating power to the inverter. Furthermore, the connectors and mating connectors of such a supply line are described, which can also be installed with an inverter.

Abstract: A circuit arrangement includes a power semiconductor switch, a freewheeling diode, and a storage choke having a core and a winding coupled between a first choke terminal and a second choke terminal. The storage choke is configured to conduct a current flowing across the power semiconductor switch. The arrangement also includes a driver circuit configured to drive the power semiconductor switch via the control terminal thereof.

Abstract: A solar module includes a safety circuit, and a series circuit of bypass diodes, which is arranged between solar module connections, wherein the bypass diodes have bypass connections at both ends and all connecting points of the series circuit of bypass diodes. The solar module also includes a series circuit of solar partial modules having partial module terminals at both ends and all connecting points of the series circuit of solar partial modules, wherein each bypass diode is associated with precisely one solar partial module, and a plurality of semiconductor switches configured to disconnect the solar module connections from voltage at an associated partial module terminal when a disconnection signal is received by the safety circuit.

Abstract: A photovoltaic energy generation system with a string including a series connection of solar modules, which string is electrically connected to an inverter via power lines for converting and feeding electrical power from the string into a network. The inverter is configured to obtain an alternative operating power from only one of the solar modules in the event that normal operating power can be obtained neither from the network nor from the entire string. A supply line can supply the alternative operating power to the inverter. Furthermore, the connectors and mating connectors of such a supply line are described, which can also be installed with an inverter.

Abstract: A circuit arrangement includes a power semiconductor switch, a freewheeling diode, and a storage choke having a core and a winding coupled between a first choke terminal and a second choke terminal. The storage choke is configured to conduct a current flowing across the power semiconductor switch. The arrangement also includes a driver circuit configured to drive the power semiconductor switch via the control terminal thereof.

Abstract: An unfolding bridge includes a half-bridge with a first input terminal, a second input terminal, and an output terminal, wherein the half-bridge includes a first bridge switch connected between the first input terminal and the output terminal and a second bridge switch connected between the second input terminal and the output terminal. The unfolding bridge also includes a further half-bridge which includes a first further bridge switch connected between the first input terminal and a further output terminal and a second further bridge switch connected between the second input terminal and the further output terminal. A switch controller for operation of the bridge switches is designed such that a connection of the output terminals with the input terminals via the bridge switches is reversed at a zero crossing of an alternating current flowing at the output terminals.

Abstract: The disclosure relates to an inverter for supplying a power provided as a DC voltage at a DC input to an AC mains connectable to an AC output. In this case, the inverter includes a switching network with a plurality of semiconductor switches and a digital control unit for producing a digital switching pattern for digitally operated semiconductor switches of the switching network that are able to be used to produce a first output voltage (Uout,dig). The inverter additionally includes a linear control unit for producing signals for actuating at least one semiconductor switch of the switching network in a linear mode, wherein the linear control unit is set up to produce a voltage drop (Uout,lin) across and/or a current (Iout,lin) through the at least one linearly operated semiconductor switch to a target value that is dependent on an instantaneous difference between the first output voltage (Uout,dig) and a voltage (UAC) of the AC mains.

Abstract: A solar module includes a safety circuit, and a series circuit of bypass diodes, which is arranged between solar module connections, wherein the bypass diodes have bypass connections at both ends and all connecting points of the series circuit of bypass diodes. The solar module also includes a series circuit of solar partial modules having partial module terminals at both ends and all connecting points of the series circuit of solar partial modules, wherein each bypass diode is associated with precisely one solar partial module, and a plurality of semiconductor switches configured to disconnect the solar module connections from voltage at an associated partial module terminal when a disconnection signal is received by the safety circuit.

Abstract: A method for the feeding of electrical current into a line branch of an electrical installation that is protected by a line protection fuse and is designed for a current up to a maximum permissible value includes feeding into the line branch an electrical current from an external energy supply network and electrical current from an energy generating system. The method further includes limiting the feeding in of the electrical current into the line branch from the external energy supply network by the line protection fuse, which prescribes a limit value for the electrical current fed into the line branch, and controlling the feeding in of the electrical current generated by the energy generating system so that no more than a specific, but variable maximum current is fed into the line branch.

Abstract: An unfolding bridge includes a half-bridge with a first input terminal, a second input terminal, and an output terminal, wherein the half-bridge includes a first bridge switch connected between the first input terminal and the output terminal and a second bridge switch connected between the second input terminal and the output terminal. The unfolding bridge also includes a further half-bridge which includes a first further bridge switch connected between the first input terminal and a further output terminal and a second further bridge switch connected between the second input terminal and the further output terminal. A switch controller for operation of the bridge switches is designed such that a connection of the output terminals with the input terminals via the bridge switches is reversed at a zero crossing of an alternating current flowing at the output terminals.

Abstract: A method for operating an inverter with reactive power capability that includes a voltage link circuit and an unfolding bridge, wherein poles of the voltage link circuit are configured to be selectively connected to terminals of an AC output in different configurations by means of the unfolding bridge, in order to change a polarity of the AC output relative to the voltage link circuit. The method includes in the case of a phase shift between an AC current (I) and an AC voltage (U) at the AC output reversing the direction of a current flowing via the voltage link circuit.

Abstract: The disclosure relates to an inverter for supplying a power provided as a DC voltage at a DC input to an AC mains connectable to an AC output. In this case, the inverter includes a switching network with a plurality of semiconductor switches and a digital control unit for producing a digital switching pattern for digitally operated semiconductor switches of the switching network that are able to be used to produce a first output voltage (Uout,dig). The inverter additionally includes a linear control unit for producing signals for actuating at least one semiconductor switch of the switching network in a linear mode, wherein the linear control unit is set up to produce a voltage drop (Uout,lin) across and/or a current (Iout,lin) through the at least one linearly operated semiconductor switch to a target value that is dependent on an instantaneous difference between the first output voltage (Uout,dig) and a voltage (UAC) of the AC mains.

Abstract: A method for operating an inverter with reactive power capability that includes a voltage link circuit and an unfolding bridge, wherein poles of the voltage link circuit are configured to be selectively connected to terminals of an AC output in different configurations by means of the unfolding bridge, in order to change a polarity of the AC output relative to the voltage link circuit. The method includes in the case of a phase shift between an AC current (I) and an AC voltage (U) at the AC output reversing the direction of a current flowing via the voltage link circuit.

Abstract: The invention relates to a process of connecting an AC output of a transformerless inverter of a solar power plant to an internal AC power grid at an input side of a galvanic isolation, while an offset voltage for shifting a potential center point of a photovoltaic generator connected to the inverter is applied. The process includes: (i) synchronizing the inverter with the power grid; (ii) essentially matching a potential center point of the current-carrying lines of the AC output and a potential center point of the power grid, while only one of the potential center points of the current-carrying lines and the power grid is yet shifted by the offset voltage; and (iii) galvanically connecting all current-carrying lines of the AC output with the power grid only after the steps of synchronizing and essentially matching.

Abstract: A method for the feeding of electrical current into a line branch of an electrical installation that is protected by a line protection fuse and is designed for a current up to a maximum permissible value includes feeding into the line branch an electrical current from an external energy supply network and electrical current from an energy generating system. The method further includes limiting the feeding in of the electrical current into the line branch from the external energy supply network by the line protection fuse, which prescribes a limit value for the electrical current fed into the line branch, and controlling the feeding in of the electrical current generated by the energy generating system so that no more than a specific, but variable maximum current is fed into the line branch.

Abstract: An AC inductor includes a core, at least one permanent magnet for magnetically biasing the core, an inductor winding on the core, and a circuitry which guides an alternating current which flows through the AC inductor in such a way through the inductor winding that, during each half-wave of the alternating current, the alternating current generates a magnetization of the core which is opposite to the magnetization by the permanent magnet. This circuitry includes a commutator which guides the alternating current flowing between two contacts of the AC inductor through the same part of the inductor winding with a same flow direction during each of the half-wave of the alternating current.

Abstract: A method for detecting an arc fault in a photovoltaic power circuit includes operating a photovoltaic generator at a first working point. A first signal related to a DC-current and/or a DC-voltage in the power circuit is determined. The first signal is analyzed and it is determined whether the signal indicates the presence of an electric arc in the power circuit. If so, the photovoltaic generator is operated at a second working point and a second signal related to the DC-current and/or the DC-voltage is determined. The first and second signals are then compared; and the occurrence of an arc fault in the power circuit is selectively signaled based on the comparison.

Abstract: The invention relates to a process of connecting an AC output of a transformerless inverter of a solar power plant to an internal AC power grid at an input side of a galvanic isolation, while an offset voltage for shifting a potential center point of a photovoltaic generator connected to the inverter is applied. The process includes: (i) synchronizing the inverter with the power grid; (ii) essentially matching a potential center point of the current-carrying lines of the AC output and a potential center point of the power grid, while only one of the potential center points of the current-carrying lines and the power grid is yet shifted by the offset voltage; and (iii) galvanically connecting all current-carrying lines of the AC output with the power grid only after the steps of synchronizing and essentially matching.

Abstract: The invention relates to a process of connecting an AC output of a transformerless inverter of a solar power plant to an internal AC power grid at an input side of a galvanic isolation, while an offset voltage for shifting a potential center point of a photovoltaic generator connected to the inverter is applied. The process includes: (i) synchronizing the inverter with the power grid; (ii) essentially matching a potential center point of the current-carrying lines of the AC output and a potential center point of the power grid, while only one of the potential center points of the current-carrying lines and the power grid is yet shifted by the offset voltage; and (iii) galvanically connecting all current-carrying lines of the AC output with the power grid only after the steps of synchronizing and essentially matching.

Abstract: A power generation system for feeding electrical power from a generation unit into a three-phase grid via three AC terminals is disclosed. The system includes a relay arrangement for disconnecting the system from the grid having at least three relays. Each of the three relays includes a control coil and two switching contacts operated by the corresponding control coil. Each of the AC terminals is connectable to the grid via a first and a second switching contact, each of which is assigned to a different one of the relays. Further disclosed are a relay arrangement and an inverter with a relay arrangement.