Abstract: A protection apparatus includes an interface, a protection switch, a direct current bus, and a controller. The apparatus is connected to at least two photovoltaic units via the interface, the at least two photovoltaic units are coupled to the direct current bus inside the apparatus to form at least two branches, and each branch is connected to at least one photovoltaic unit. The protection switch is configured to disconnect all or some of the photovoltaic units from the direct current bus, to enable a maximum of three photovoltaic units to be directly connected in parallel. According to the apparatus, a photovoltaic unit and a line are protected with a low power loss when a photovoltaic inverter is faulty.

Abstract: Embodiments of this application disclose an inverter apparatus and an inverter apparatus control method. The inverter apparatus includes an inverter circuit and a control unit, and the control unit detects a driving mode of the inverter circuit based on a running state of the inverter circuit. When the inverter circuit outputs reactive power and an output current amplitude is greater than a current threshold, the control unit controls the inverter circuit in a full-bridge two-level bipolar control mode; and in other cases, the control unit controls the inverter circuit in a three-level control mode. This reduces a risk of breaking down horizontal bridge semiconductor switching devices by a voltage spike in an active turn-off process.

Abstract: A photovoltaic system includes a plurality of photovoltaic strings, at least one junction device, and at least one inverter. Each photovoltaic string includes a first direct current output terminal, and is configured to generate a first direct current. Each junction device is coupled to the plurality of photovoltaic strings. Each junction device is configured to output second direct currents through second direct current output terminals of the junction device after converging a plurality of first direct currents. An ith junction device includes a plurality of second direct current output terminals. The ith junction device is configured to output a plurality of mutually independent second direct currents after converging a plurality of first direct currents, and i is a positive integer. A quantity of the plurality of second direct currents is less than a quantity of the plurality of first direct currents.

Abstract: Embodiments of this application disclose an arc detection method for performing protection in an energy storage system, and a related apparatus, to improve accuracy of arc detection in an energy storage system, promptly take an arc extinguishing measure, and reduce a probability of causing a safety hazard. The method in the embodiments of this application includes: A control apparatus obtains an electrical signal at an electrical connection point in an energy storage system. The control apparatus determines a frequency domain amplitude based on a frequency domain characteristic of the electrical signal. When the frequency domain amplitude is greater than a preset amplitude, the control apparatus controls the energy storage system to perform an arc extinguishing and protection operation on the electrical connection point.

Abstract: A protection apparatus includes an interface, a protection switch, a direct current bus, and a controller. The apparatus is connected to at least two photovoltaic units via the interface, the at least two photovoltaic units are coupled to the direct current bus inside the apparatus to form at least two branches, and each branch is connected to at least one photovoltaic unit. The protection switch is configured to disconnect all or some of the photovoltaic units from the direct current bus, to enable a maximum of three photovoltaic units to be directly connected in parallel. According to the apparatus, a photovoltaic unit and a line are protected with a low power loss when a photovoltaic power generation system is faulty.

Abstract: This application provides a charging module and a charging system. The charging system includes a charging module. The charging module includes a direct current-to-direct current (DC/DC) charging component, a functional interface, an inverter, and a control and guide component. The functional interface includes a photovoltaic interface. The DC/DC charging component is configured to receive a first power exported by a photovoltaic module to charge an electric vehicle (EV). In this way, after receiving, through the photovoltaic interface, electrical energy converted from solar energy, the charging module does not need to cooperate with an on-board charger (OBC), but uses the DC/DC charging component to charge the EV with a direct current. The charging module provided in this application is not limited by a charging power of the OBC when charging the EV, thereby increasing an actual power for charging the EV and a charging speed.

Abstract: A linkage protection system includes an inverter, an anti-potential-induced degradation (PID) apparatus, and an insulation-monitoring apparatus. The anti-PID apparatus is configured to inject a voltage into an input end or an output end of the inverter, to increase or decrease a voltage-to-earth of a photovoltaic system. The insulation-monitoring apparatus is configured to inject an insulation-monitoring voltage into a direct current (DC) side or an alternating current (AC) side of the inverter. The anti-PID apparatus and the insulation-monitoring apparatus directly or indirectly communicate with each other, to learn of information about whether a peer apparatus is operating, and perform linkage control. The anti-PID apparatus and the insulation-monitoring apparatus operate in different time periods.

Abstract: An energy combiner apparatus is used to convert output of a power supply, and has three output terminals, so that output ports are increased. In the three output terminals of the energy combiner apparatus, a voltage of 1500 V is output between a first output terminal and a second output terminal, a voltage of 1500 V is also output between the second output terminal and a third output terminal, and a total of 3 kV is output. Therefore, an overall output voltage is increased in a case of equal output power. Because the overall output voltage is increased, a current transmitted on a cable may be reduced. Therefore, a thinner cable may be used, so that costs of the cable are reduced. In addition, four cables conventionally required for connecting to the output terminals of the energy combiner apparatus are reduced to three, so that quantity and costs are reduced.

Abstract: A method and an apparatus for detecting a solar cell of a photovoltaic plant. The method includes: obtaining a first infrared image and a second infrared image, where the first infrared image includes infrared image information corresponding to an ambient infrared signal reflected by a to-be-detected solar cell operating in a short-circuit state, the second infrared image includes infrared image information corresponding to an infrared signal emitted by the to-be-detected solar cell operating in a first state and infrared image information corresponding to an ambient infrared signal reflected by the to-be-detected solar cell, and the first state is another state other than the short-circuit state; and detecting, based on the first infrared image and the second infrared image, whether the to-be-detected solar cell has a defect.

Abstract: A power system is disclosed. Output terminals of a power supply or a DC-to-DC unit are cascaded to increase an output voltage, so as to reduce a current between the power supply or the DC-to-DC unit and the DC-to-AC unit, and resolve cost and loss problems of the cable from the power supply or the DC-to-DC unit to the DC-to-AC unit. In addition, according to the power system provided in the embodiments of this application, a quantity of cables from the power supply or the DC-to-DC unit to the DC-to-AC unit may be further reduced by cascading output terminals of the power supply or the DC-to-DC unit and cascading inputs of the DC-to-AC unit, thereby reducing system costs. In addition, in the power system provided in the embodiments of this application, cascaded input and isolated output of the DC-to-AC unit can reduce a specification of a power conversion device.

Abstract: A photovoltaic power generation system includes a protection switch and a plurality of DC-DC converters. Each DC-DC converter includes a direct current bus, a DC-DC circuit, and at least one input interface. The input interface is configured to connect to a photovoltaic unit. The photovoltaic unit includes at least one photovoltaic module. The input interface is connected to the direct current bus by using the protection switch, the direct current bus is connected to an input end of the DC-DC circuit, and an output end of the DC-DC circuit is an output end of the DC-DC converter. The protection switch includes a release device and a switching device that are connected in series. The release device is configured to: when a short-circuit fault occurs on a line in which the release device is located, control the switching device to be disconnected.

Abstract: Embodiments of this application provide a power system. An output terminal of a power supply or a DC-to-DC unit is cascaded. In addition, according to the power system provided in embodiments of this application, a quantity of cables from the power supply or the DC-to-DC unit to the DC-to-AC unit may be further reduced by cascading an output terminal of the power supply or the DC-to-DC unit and cascading an input of the DC-to-AC unit.

Abstract: A photovoltaic system, an optimizer, a controller, a computer program product, a computer-readable storage medium, a chip, and a method for adjusting a working state of an optimizer are provided. The photovoltaic system includes a photovoltaic panel and an optimizer. The optimizer includes a controller, a first output port, and a second output port. The controller is configured to detect an electrical signal parameter between the first output port and the second output port. The controller is configured to adjust a working state of the optimizer from a no-output state or a limited-output state to an unlimited-output state when the electrical signal parameter changes. In the photovoltaic system, the working state can be adjusted without using an unlocking apparatus, so that an implementation is simple, and costs are reduced.

Abstract: A fault detection apparatus includes an image capture module and a detection module, and the fault detection apparatus is configured to capturing an image of the photovoltaic module in a light emitting state, and performing fault detection on the photovoltaic module based on the image when a signal-to-noise ratio of the image is maximized, to identify a fault type of the photovoltaic module.

Abstract: An energy storage system includes one or more energy storage unit clusters, and the energy storage unit cluster includes at least two energy storage modules connected in series. The energy storage system further includes a first bus, a second bus, and a centralized monitoring system of the energy storage unit cluster, where the second bus is a direct current bus. The energy storage unit cluster is coupled to the first bus by using a first converter. One energy storage module includes one energy storage element group and one DC/DC converter, and the energy storage element group is coupled to the second bus by using the DC/DC converter. The centralized monitoring system is connected to the energy storage unit cluster through a control bus, and is configured to control a DC/DC converter in any energy storage module in the energy storage unit cluster.

Abstract: A photovoltaic power generation system includes a protection switch and a plurality of DC-DC converters. Each DC-DC converter includes a direct current bus, a DC-DC circuit, and at least one input interface. The input interface is configured to connect to a photovoltaic unit. The photovoltaic unit includes at least one photovoltaic module. The input interface is connected to the direct current bus by using the protection switch, the direct current bus is connected to an input end of the DC-DC circuit, and an output end of the DC-DC circuit is an output end of the DC-DC converter. The protection switch includes a release device and a switching device that are connected in series. The release device is configured to: when a short-circuit fault occurs on a line in which the release device is located, control the switching device to be disconnected.

Abstract: A power supply system includes at least one group of power supply modules. The power supply module includes a first string, a first residual current detection circuit, an inverter circuit, and a first controller. The first residual current detection circuit is connected between the first string and an input end of the inverter circuit, and an output end of the inverter circuit is connected to an alternating current power grid. When a first residual current value detected by the first residual current detection circuit is greater than a first preset residual current threshold, the first controller controls the first string to be disconnected from the inverter circuit, or controls the inverter circuit to be disconnected from the alternating current power grid.

Abstract: The present disclosure discloses an energy storage converter, wherein a first end of the energy storage converter is coupled to at least one of the Q cell strings, and second end of the energy storage converter is configured to connect to a power grid. The first energy storage converter includes a DC/AC conversion unit and at least one DC/DC conversion unit. The DC/DC conversion unit is configured to perform adaptation between a voltage of the DC/AC conversion unit and a voltage of a cell string. Therefore, a cell capacity is fully used, and a waste of the cell capacity is reduced.

Abstract: A data processing system in the power station operation and maintenance system may determine a faulty module and a normal module based on module data of each photovoltaic module in a photovoltaic string, and obtain first power generation data of the faulty module and second power generation data of the normal module. Further, the data processing system may determine an annual lost energy yield of the faulty module based on the first power generation data, the second power generation data, and a preset energy yield of the photovoltaic power station, and obtain a target operation and maintenance measure from a plurality of operation and maintenance measures based on the annual lost energy yield. In this case, a communication system in the power station operation and maintenance system may notify an operation and maintenance user of the photovoltaic power station to perform operation and maintenance on the faulty module.

Abstract: A protection apparatus includes an interface, a protection switch, a direct current bus, and a controller. The apparatus is connected to at least two photovoltaic units via the interface, the at least two photovoltaic units are coupled to the direct current bus inside the apparatus to form at least two branches, and each branch is connected to at least one photovoltaic unit. The protection switch is configured to disconnect all or some of the photovoltaic units from the direct current bus, to enable a maximum of three photovoltaic units to be directly connected in parallel. According to the apparatus, a photovoltaic unit and a line are protected with a low power loss when a photovoltaic power generation system is faulty.