Abstract: The disclosure describes a method for detecting an arc in a direct-current (DC) circuit comprising a DC load, a DC source supplying the DC load, and a circuit arrangement arranged between the DC source and the DC load. A power flow P between an input and an output of the circuit arrangement is suppressed by means of a switching circuit through cyclical interruption such that the power flow P is enabled in an active time window with the first period ?t1 and the power flow P is suppressed in an inactive time window with the second period ?t2.
Type:
Grant
Filed:
July 15, 2022
Date of Patent:
October 29, 2024
Assignee:
SMA Solar Technology AG
Inventors:
Marcel Kratochvil, Rainer Schmitt, Torsten Otto, Sybille Pape
Abstract: The disclosure is directed to a detection device for detecting a fault current (Ifault) at a PV generator and/or at DC lines of a PV installation assigned to the PV generator. The PV generator has at least one first PV string and a second PV string, which are connected to a PV inverter of the PV installation via in each case two DC lines. In this case, the detection device has at least one current transformer and an evaluation circuit connected to the at least one current transformer. The current transformer can be used jointly by the first PV string and the second PV string, wherein a measurement signal of the jointly usable current transformer represents a difference between a first summation current (Isum,1) flowing from the first PV string towards the ground potential (PE) and a second summation current (Isum,2) flowing from the second PV string towards the ground potential (PE).
Abstract: A method and associated system for determining an operating parameter of a PV installation having a plurality of PV modules is disclosed. The PV modules each include a shutdown apparatus connected to a transmission apparatus of the PV installation and has a feed-in operation and a shutdown operation. At least one PV module is equipped with a power-optimizing device which is configured to set an operating point of the PV module in an optimizing operation. The method includes determining a first total electrical power of the PV modules in a non-optimizing operation of the at least one power-optimizing device and in the feed-in operation of the shutdown apparatuses, and determining a second total electrical power of the PV modules in the optimizing operation of all the power-optimizing devices and in the feed-in operation of the shutdown apparatuses.
Abstract: A method is disclosed for stabilizing a DC voltage in a DC grid that includes a DC bus connected to a higher-order grid and to which an energy generating system and at least one load are connected.
Abstract: A circuit arrangement for balancing a split DC link arranged between a first DC-voltage terminal and a second DC-voltage terminal is disclosed. The first DC-voltage terminal is connected via a first semiconductor switch to a first intermediate point that is connected via a second semiconductor switch to a bridge center point that is connected via a third semiconductor switch to a second intermediate point that is connected via a fourth semiconductor switch to the second DC-voltage terminal. A first terminal of a resonant capacitor is connected to the first intermediate point, and a second terminal of the resonant capacitor is connected to a DC-link center point via a connecting path, in which a resonant inductor is arranged in a series circuit with the third semiconductor switch, and which runs via the second intermediate point.
Abstract: A changeover device for selectively supplying power to at least one load from a grid or a bidirectional inverter includes an input having a grid neutral conductor connection and a grid phase conductor connection for connection to the grid. The changeover device further includes a first output having an inverter neutral conductor connection and an inverter phase conductor connection for connecting the bidirectional inverter, a second output having a load neutral conductor connection and a load phase conductor connection for connecting the load and a switching circuit, the actuator of which is connected to an actuator input of the changeover device. The switching circuit includes a first and a second normally closed contact and a normally open contact that are connected in an interconnection to the grid phase conductor connection, the inverter phase conductor connection, and the load phase conductor connection. An associated method is also disclosed.
Abstract: A described method for operating a battery converter in a system, in which, in addition to the battery converter, an inverter, which is connected to a grid, and a DC load are connected to a common intermediate circuit via a DC bus, includes: —controlling an exchange power of the battery converter using a battery, which is connected to the battery converter, depending on a voltage of the intermediate circuit in accordance with a converter characteristic curve, —identifying a decrease in the intermediate circuit voltage below a rectifying value of the permissible AC voltage of the grid connected to the inverter, and—if the decrease is identified, temporarily shifting the converter characteristic curve so that a maximum discharging power of the battery converter is reached at a value of the intermediate circuit voltage that is above or at the rectifying value. A battery converter, which is configured to carry out the method, and a system having such a battery converter are also described.
Abstract: A method for measuring insulation resistance in an inverter that has a DC link circuit and a bridge circuit, connected to the DC link circuit, for driving an AC current via a bridge center tap is disclosed. The method includes connecting the bridge center tap to a grounding point, successively connecting, by way of the bridge circuit, the bridge center tap that is connected to the grounding point to two points of the ungrounded DC link circuit that differ in terms of voltage, and measuring the current flowing from the two points that differ in terms of voltage to the grounding point. The two points of the ungrounded DC link circuit that differ in terms of voltage are selected from a group of points that includes at least one intermediate voltage point of the DC link circuit in addition to two end points of the DC link circuit, such that the voltages present between the two points that differ in terms of voltage and the grounding point do not exceed a predefined voltage limit value.
Abstract: A method for identifying an assignment of phase lines of an electrical distribution grid to connections of an electrical device capable of unbalanced-load operation, wherein the device is connected to a plurality of phase lines of the electrical distribution grid, includes setting target parameters assigned to an unbalanced load profile at each of the connections of the electrical device, detecting a temporal profile of a measurement parameter on each of the plurality of phase lines using a detection circuit, comparing the detected temporal profiles of the measurement parameters with the target parameters of the unbalanced load profile for each of the plurality of phase lines, respectively, and identifying the assignment of the phase lines to the connections on the basis of the comparison.
Abstract: The disclosure relates to a housing of an electrical device for converting electrical power, including a main body and a cover. The cover closes the main body to define a self-contained interior space, wherein electrical and electronic components of the electrical device are arranged in the interior space of the housing. The cover is connected to the main body via a detchable securing structure, which may be arranged in the geometrical center of the cover. An electrical device has a housing of this type.
Type:
Grant
Filed:
February 24, 2022
Date of Patent:
July 2, 2024
Assignee:
SMA Solar Technology AG
Inventors:
Sven Bremicker, Martin Dziuba, Waissi Tello
Abstract: A local power supply system having a grid transfer point for the connection of an energy supply grid has a first transmission line for transmitting electrical energy from the grid transfer point to a first terminal for connecting an arrangement of consumers, and a second transmission line for transmitting electrical energy between the grid transfer point and a second terminal for connecting an arrangement of energy stores. A first disconnector is arranged in the first transition line between the grid transfer point and the first terminal, and a second disconnector is arranged in the second transmission line between the grid transfer point and the second terminal.
Abstract: A power electronics device has a first power semiconductor switch and a driver circuit and enables a supply of electrical voltage to a driver circuit. An auxiliary circuit arrangement has a supply capacitor, an auxiliary capacitor, a normally off auxiliary semiconductor switch, a diode and a bootstrap diode. The auxiliary semiconductor switch is connected to a reference potential connection of the first power semiconductor switch via a connection point, starting from the connection point, a series connection of the diode, a second connection point and the auxiliary capacitor is arranged in parallel with the auxiliary semiconductor switch. When the auxiliary semiconductor switch is in the off state, the auxiliary capacitor is charged by the flow of current through the first power semiconductor switch.
Abstract: The disclosure relates to a platform for the space-saving formation of an energy conversion system. In this, containers are stacked one above the other as housings of components of the energy conversion system with the platform arranged between the containers, wherein the platform has a frame structure which has, on a first side, first alignment elements for placing the platform on a first container and, on a second side, opposite the first side, of the frame structure, second alignment elements for placing a second container on a placement area of the frame structure. The first and second alignment elements are arranged in such a way that they result in an arrangement, which is laterally centered and vertically spaced apart by a height (H) of the platform, of the second container above the first container, wherein the frame structure forms a standing area, which circumferentially surrounds the placement area and is walkable by persons, as access to the second container.
Abstract: The disclosure relates to a power electronics device having at least two inverters and a transformer apparatus having a core arrangement, at least one primary winding and at least one secondary winding that wind around the core arrangement at least in sections.
Abstract: A method for switching off power semiconductor switches in a bridge circuit having first through sixth power semiconductor switches. The method includes a switch-off process for establishing a final switch configuration in which all power semiconductor switches in the bridge circuit are in a switched-off state. Over the course of the switch-off process, a switch configuration is established in which the fifth power semiconductor switch and the sixth power semiconductor switch are concurrently in a switched-on state, while the first power semiconductor switch and the fourth power semiconductor switch are in a switched-off state. Also disclosed is a bridge circuit having a control circuit configured to carry out such a method. In addition, an inverter that includes at least one bridge circuit of this type is also provided.
Abstract: The disclosure relates to a method for determining a characteristic curve for a photovoltaic (PV) string of a photovoltaic system having an inverter which is connected to the photovoltaic string and to a power supply network. The photovoltaic string includes a series connection of a plurality of photovoltaic modules, in which series connection at least one of the photovoltaic modules is integrated into the series connection of the photovoltaic modules via a DC/DC converter. The at least one DC/DC converter operates the photovoltaic module assigned thereto in a first operating mode M1 at a maximum power point by varying, over time, a conversion ratio of output voltage (UOut) to input voltage (UIn), and operates the photovoltaic module in a second operating mode M2 with a conversion ratio of output voltage (UOut) to input voltage (UIn) that is constant over time.
Type:
Grant
Filed:
December 17, 2021
Date of Patent:
January 30, 2024
Assignee:
SMA Solar Technology AG
Inventors:
Michael Viotto, Markus Hopf, Bernhard Schropp
Abstract: A method for operating an electrolysis device, having a converter which is connected on an AC voltage side to an AC voltage grid via a decoupling inductance and draws an AC active power from the AC voltage grid, and an electrolyzer, which is connected to the converter on the DC voltage side, is provided. The method includes operating the electrolysis device, when a grid frequency corresponds to a nominal frequency of the ACT voltage grid and is substantially constant over a time period, with an electrical power which is between 50% and 100% of a nominal power of the electrolyzer, and operating the converter in a voltage-impressing manner, such that an AC active power drawn from the AC voltage grid is changed on the basis of a change and/or a rate of change of the grid frequency in the AC voltage grid.
Abstract: A method for three-phase infeed of electrical power from a DC source into a three-phase AC grid by means of an inverter includes measuring phase-specific grid voltages of the three-phase AC grid, and determining a grid frequency from the measured phase-specific grid voltages. The method also includes generating phase-specific voltage reference values from the phase-specifically measured grid voltages and the determined grid frequency, and generating phase-specific target current values using phase-specific predetermined target current amplitude values, the phase-specific voltage reference values and respective grid voltage amplitudes.
Type:
Grant
Filed:
September 13, 2021
Date of Patent:
December 26, 2023
Assignee:
SMA Solar Technology AG
Inventors:
Alexander Unru, Moritz Welker, Neidhardt Bechtel, Sybille Pape
Abstract: The disclosure relates to a method and related device for approximately determining voltages at a high-voltage side of a transformer on the basis of measured voltages at a low-voltage side of the transformer.
Abstract: A method of detecting a serial arc fault in a DC-power circuit includes injecting an RF-signal with a narrow band-width into the DC-power circuit and measuring a response signal related to the injected RF-signal in the DC-power circuit. The method further includes determining a time derivative of the response signal, analyzing the time derivative, and signaling an occurrence of a serial arc fault in the power circuit based on the results of the analysis. A system for detecting an arc fault is configured to perform a method as described before.