Abstract: A method for detecting a potential-induced degradation (PID) of PV modules of a PV installation includes operating a PV generator at a maximum power point (MPP), at a first generator voltage (U1) and first generator current (I1), and at a second generator voltage (U2) and second generator current (I2), where a first power (P1) at the first generator voltage (U1) is in a predefined first ratio V1=P1/PMPP and V1?1, with the power (PMPP) at the maximum power point (MPP) of the PV generator, and where a second power (P2) at the second generator voltage (U2) is in a predefined second ratio V2=P2/P1 and V2<1, with the first power (P1) of the PV generator, and where a quantity Y that characterizes a progress of the potential-induced degradation (PID) is determined from the values of the voltages (U1, U2) and/or the currents (I1, I2).

Abstract: A method and associated device for detecting arcs in a photovoltaic system with an inverter and with a plurality of current collector circuits connected in parallel with the inverter via collector lines, wherein a plurality of strings of photovoltaic modules are connected in parallel with each current collector circuit via string lines. The method includes acquiring measured values of electrical variables and analyzing the measured values of the electrical variables for the presence of signs of an arc in the photovoltaic system using an analysis circuit and generating an arc signal which indicates the presence of an arc if the analyzed measured values meet predefined criteria. The method also includes acquiring measured values of acoustic variables using one or more acoustic sensors, and analyzing the measured values of the acoustic variables for the presence of signs of an arc in the photovoltaic system using the analysis circuit.

Abstract: A method for detecting a potential-induced degradation (PID) of PV modules of a PV installation, having a measurement pass, includes operating a PV generator of the PV installation at a maximum power point (MPP) with values of generator voltage (UMPP) and generator current (IMPP) associated with the maximum power point (MPP), and operating the PV generator of the PV installation at a first generator voltage (U1) and detection of a first generator current (I1) associated with the first generator voltage (U1).

Abstract: A method and associated device for detecting arcs in a photovoltaic system with an inverter and with a plurality of current collector circuits connected in parallel with the inverter via collector lines, wherein a plurality of strings of photovoltaic modules are connected in parallel with each current collector circuit via string lines. The method includes acquiring measured values of electrical variables and analyzing the measured values of the electrical variables for the presence of signs of an arc in the photovoltaic system using an analysis circuit and generating an arc signal which indicates the presence of an arc if the analyzed measured values meet predefined criteria. The method also includes acquiring measured values of acoustic variables using one or more acoustic sensors, and analyzing the measured values of the acoustic variables for the presence of signs of an arc in the photovoltaic system using the analysis circuit.

Abstract: The disclosure relates to a method for signaling partial shadowing within a PV generator including at least two partial PV generators connected in parallel. The method includes performing a reference impedance measurement on each of the at least two partial PV generators in a state of uniform irradiation of the PV generator, and determining at least one reference resonant property of each of the at least two partial PV generators from the reference impedance measurement. Furthermore, impedance measurements are carried out on the at least two partial PV generators at a first operating point of the PV generator during operation of the PV generator. Resonant properties of the partial PV generators are determined from the impedance measurements. Partial shadowing within the PV generator is detected and signaled if a difference between the resonant properties of the partial PV generators at the first operating point differs from a difference between the reference resonant properties of the partial PV generators.

Abstract: The disclosure relates to a circuit arrangement for suppressing an arc occurring during a switching process, wherein a current bypass path comprises a PTC resistor connected in series with a fuse. The current bypass path is provided in parallel with a switch. The disclosure also relates to a photovoltaic power plant with a photovoltaic generator which is connected to an inverter via DC lines. In this arrangement, such a circuit arrangement is arranged in at least one of the DC lines.

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 disclosure relates to a method for signaling partial shadowing within a PV generator including at least two partial PV generators connected in parallel. The method includes performing a reference impedance measurement on each of the at least two partial PV generators in a state of uniform irradiation of the PV generator, and determining at least one reference resonant property of each of the at least two partial PV generators from the reference impedance measurement. Furthermore, impedance measurements are carried out on the at least two partial PV generators at a first operating point of the PV generator during operation of the PV generator. Resonant properties of the partial PV generators are determined from the impedance measurements. Partial shadowing within the PV generator is detected and signaled if a difference between the resonant properties of the partial PV generators at the first operating point differs from a difference between the reference resonant properties of the partial PV generators.

Abstract: The disclosure relates to a circuit arrangement for suppressing an arc occurring during a switching process, wherein a current bypass path comprises a PTC resistor connected in series with a fuse. The current bypass path is provided in parallel with a switch. The disclosure also relates to a photovoltaic power plant with a photovoltaic generator which is connected to an inverter via DC lines. In this arrangement, such a circuit arrangement is arranged in at least one of the DC lines.

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.