Abstract: A DC/DC converter includes a first low-voltage terminal point, a second low-voltage terminal point and a third low-voltage terminal point, and a first high-voltage terminal point and a second high-voltage terminal point. The first low-voltage terminal point and the first high-voltage terminal point are directly connected to one another, and an actively drivable switching element, a capacitor and a further switching element are connected in series between the first high-voltage terminal point and the second high-voltage terminal point. The capacitor is connected between the second low-voltage terminal point and the third low-voltage terminal point, a further capacitance is directly connected between the second low-voltage terminal point and the third low-voltage terminal point, and the further capacitance is decoupled from the capacitor at two terminals by two inductors, respectively.

Abstract: For determining the topology of a grid section of an AC power grid, the grid section comprising a grid connection point, at least one branch branching off from the grid connection point and including a plurality of energy consumption and/or energy generation units, and at least one measurement point in the at least one branch, dependencies of variations of a grid voltage measured at the at least one measurement point based on variations of connection power values of at least some individual ones of the energy consumption and/or energy generation units are determined.

Abstract: An inverter has an inverter bridge connected between two DC busbars on the input side and connected to an AC output on the output side. The two DC busbars run, in a manner overlapping one another, in planes which are parallel to one another. The inverter bridge has a subcircuit having a plurality of semiconductor switches between the AC output and each DC busbar. Semiconductor modules which form the two subcircuits are connected, in a manner arranged beside one another, to the two DC busbars and to the AC output via connections. A connection element which leads to the AC output begins on that side of the DC busbar which faces the semiconductor modules in a region overlapped by the DC busbars and connects the semiconductor modules of the two subcircuits to one another there.

Abstract: A photovoltaic system having an inverter and a photovoltaic generator connected to an inverter input is configured to track an operating voltage of maximum power from the photovoltaic generator. The system also includes an energy store coupled in parallel with the photovoltaic generator, to the input of the inverter. A temporal profile of the power output by the photovoltaic generator is recorded by the converter and compensates for fluctuations in power from the photovoltaic generator in comparison with a target power by adapting the power (PDC) output by it at the input or branched off from there in such a manner that the sum of the power (PDC) from the converter and the power (PPV) from the photovoltaic generator is equal to the target power (PSoll). The converter is operated in a tracking mode that it makes it possible to track the operating voltage of maximum power by means of the inverter.

Abstract: In a circuit arrangement for in-line supply of voltage to an electrical or electronic apparatus located in the region of a DC line, a parallel circuit of two diodes oriented in anti-parallel is arranged in the line. When a direct current is flowing between terminals of the circuit arrangement, the anti-parallel diodes permit a small voltage drop between the terminals, irrespective of the direction of flow of the current, which voltage drop is limited to the forward voltage of the diode that is currently forward biased. The voltage drop across the anti-parallel diodes is tapped by a supply subcircuit. A semiconductor switch can be connected in parallel with the anti-parallel diodes, which switch is controlled by a voltage-reduction subcircuit to minimize the power dissipation of the circuit arrangement.

Abstract: An apparatus for determining insulation resistance at a PV generator includes a first unit configured to shift a generator potential at an output terminal of the PV generator, and a second unit. The second unit is configured to determine the insulation resistance by: connecting a measurement voltage to the output terminal of the PV generator, measuring a first current value and a first voltage value at the output terminal of the PV generator before the measurement voltage is connected, measuring a second current value and a second voltage value at the output terminal of the PV generator after the measurement voltage is connected, and determining the insulation resistance of the PV generator based on the measured first and second current values and the measured first and second voltage values. The first and second units are connected in series.

Abstract: An apparatus for establishing a multi-phase electrical connection including at least one connecting element per phase, wherein each connecting element comprises two busbars and a number (N) of substantially identical, flexible conductors arranged in parallel with one another in a plane, said conductors electrically conductively connecting the two busbars. Further, a spacing (a) of geometric center points of cross sections of adjacent conductors from one another is at least twice as large as an equivalent diameter (d, dequiv) of one of the conductors, and each busbar respectively comprises a connection region for electrical and mechanical connection of the connecting element to an electrical device.

Abstract: A method and associated apparatus for operating a power station of fluctuating electrical capacity that, besides a voltage-setting system former outputting active power and reactive power and at least one load, is connected to a limited AC grid. The method and associated apparatus includes defining a desired self-contained operating range of the system former on the PQ level, in which operating range the system former is able to efficiently correct fluctuations arising in a mains voltage of the AC grid, ascertaining a present operating point of the system former on the PQ level, and controlling an output of active power and reactive power by the power station such that the operating point of the system former is kept in the desired operating range.

Abstract: A method and corresponding system for operating an inverter includes setting an input voltage (UPV) of the inverter by an input-side DC-DC converter and/or an output-side inverter bridge, wherein the input voltage (UPV) corresponds to an MPP voltage (UMPP) at which a generator connectable on the input side outputs a maximum electrical power, and determining a first temperature value (TDCDC) in the DC-DC converter and a second temperature value (TDCAC) in the inverter bridge.

Abstract: A method for connecting an energy generation installation to a medium-voltage grid includes determining a calibration factor for adjusting first voltage values to second voltage values by a controller of the energy generation installation. During an idle state of a medium-voltage transformer, the first voltage values are detected at a capacitive voltage divider, arranged on the medium-voltage side of the medium-voltage transformer, and the second voltage values are detected by a voltage detection means, arranged on the low-voltage side of the medium-voltage transformer. The method further includes closing a circuit breaker arranged on the medium-voltage side of the medium-voltage transformer by the controller of the energy generation installation, when voltage values determined at the capacitive voltage divider exceed a first threshold value after the calibration factor has been applied.

Abstract: An inductor assembly is disclosed that includes a magnetic core with a center leg and a number n of phase legs, wherein n is an integer and n>1. Each phase leg is magnetically connected to the center leg by an upper bridge and a lower bridge to form a magnetic main loop, a midpoint of the phase leg being magnetically connected to a center point of the center leg by a shunt element including a gap. Each phase leg further includes an upper inductor coil disposed on an upper phase leg section located between the midpoint and the upper bridge and a lower inductor coil disposed on a lower phase leg section located between the midpoint and the lower bridge. Alternatively, the upper and lower inductor coils are disposed on respective upper and lower bridges.

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: The disclosure relates to an inverter, in particular for a photovoltaic system, including a housing with at least one chamber and a cooling air channel formed within the chamber for guiding ambient air as cooling air for electrical and/or electronic components of the inverter disposed along the cooling air channel. The cooling air channel extends through the housing from an air inlet to an air outlet. The inverter includes a further air outlet provided within the cooling air channel between two of the components to be cooled, and is arranged above the air inlet and the air outlet. The disclosure further relates to a method of cooling such an inverter.

Abstract: In order to measure a choke current through a choke, a flux density of a magnetic field which is emitted by the choke is consecutively measured at a sampling rate at a location which is fixed in relation to the choke. A magnetic bias of the choke is ascertained from the measurement values of the flux density at a known choke current which occurs during operation of the choke, wherein the choke current is known only in longer time intervals than the inverse value of the sampling rate during measurement of the flux density. The actual choke current is determined from the actual measurement values of the flux density taking into account the ascertained magnetic bias.

Abstract: A method for determining capacitance values of capacitances of a photovoltaic system including a multiphase inverter which includes an output current filter on an alternating current side thereof and is connected to a multiphase energy supply network via a switching element and is associated with at least one intermediate circuit capacitance on the direct current side thereof is provided.

Abstract: The disclosure relates to an integral inductor arrangement with at least three magnetic loops arranged side by side to each other in a row and at least one winding associated with each of the magnetic loops. The magnetic loops are formed by individual core elements, each of which being part of one of the magnetic loops, and shared core elements, each of which being part of two adjacent of the magnetic loops. The shared core elements are separated from the individual core elements by magnetic gaps and each of the at least one winding is arranged around one of the individual core elements. The disclosure further relates to a use of such integral inductor arrangement within a 3-phase AC-filter for a power inverter for feeding electrical power into a power grid.

Abstract: Embodiments discussed herein include an inverter with a multi-part housing and internal cooling-air duct. In one example, the inverter can comprise a first housing part with direct current connections, a second housing part with alternating current connections, a third housing part for accommodating power-electronics components of a DC voltage converter, a fourth housing part for accommodating power-electronics components of an inverter bridge circuit, and a heat sink. The housing parts each have an essentially planar rear wall and are arranged in such a way that they enclose a cooling-air duct with an essentially rectangular cross section, wherein the first housing part is arranged opposite the second housing part and the third housing part is arranged opposite the fourth housing part. The heat sink has two essentially planar cooling faces opposite one another arranged in the cooling-air duct.

Abstract: A method for controlling a load by providing a total energy consumption and a time window for the total energy consumption of the load from one or more energy sources is described. The method includes determining of energy blocks, wherein the energy blocks are based on a power interval during a time interval, the time intervals are within the time window and the energy blocks are allocated energy-source-dependent costs, sorting of the energy blocks in ascending order according to the level of the costs per energy block and subsequent summation of quantities of energy that the energy blocks contain in ascending order of sorting until the total energy consumption of the load is reached.

Abstract: A method for operating an inverter, the DC voltage input of which is connected to a positive pole (PV+) and to a negative pole (PV?) of a PV generator and the AC voltage output of which is connected to an AC grid via a transformer, is disclosed. The method includes determining a potential of the positive pole and/or the negative pole (UPV+, UPV?) of the PV generator with respect to a ground potential by a monitoring circuit, and selecting a modulation method for controlling power switches of the inverter from a number of modulation methods stored in a storage device of the inverter based on the determined potential (UPV+, UPV?) such that a voltage stress on components of the PV system arranged on the AC side, with respect to ground, is reduced. The method further includes using the selected modulation method to control the power switches for the purpose of converting a DC input voltage into an AC output voltage.

Abstract: The present disclosure relates to a photovoltaic power installation configured to deliver power to a power distribution grid at a point of common coupling, the photovoltaic power installation including a determination unit configured to determine an amount of self-consumed power of the photovoltaic power installation, and a first power inverter configured to generate power in accordance with 1) the determined amount of self-consumed power, and 2) a power level to be delivered at the point of common coupling. The disclosure further relates to an associated method.