The present disclosure is directed to a safety device for photovoltaic installations. The safety device includes a first terminal adapted to connect to a first output terminal of a solar panel, a second terminal adapted to connect to a second output terminal of the solar panel, a first switching module connected between the first terminal and the second terminal. The first switching module comprising a first switch and a first impedance connected in series. The first impedance includes one terminal connected to the first terminal and the first switch includes one terminal connected to the second terminal. A control module is adapted to read a control signal and drive the operation of the first switch based on the read value of the control signal. A powersupply means is adapted to supply power to the control module.

A combiner box includes a switching device, a sampling circuit, and a controller. The switching device is connected in parallel between a positive input port and a negative input port. The sampling circuit is configured to collect at least one of an input parameter and an output parameter of the combiner box. The controller is configured to control the switching device to be closed when determining, based on the at least one parameter, that a short circuit occurs between a positive output cable and a negative output cable or a positive output cable and a negative output cable are reversely connected, so that the switching device, the positive input port, and the negative input port form a closed loop.

A combiner box includes a switching device, a sampling circuit, and a controller. The switching device is connected in parallel between a positive input port and a negative input port. The sampling circuit is configured to collect at least one of an input parameter and an output parameter of the combiner box. The controller is configured to control the switching device to be closed when determining, based on the at least one parameter, that a short circuit occurs between a positive output cable and a negative output cable or a positive output cable and a negative output cable are reversely connected, so that the switching device, the positive input port, and the negative input port form a closed loop.

A solar power generation system includes: solar cells, or solar cells and at least one capacitor, connected in series between output terminals; an accompanying circuit provided for each of the solar cells, or each of the solar cells and each of the at least one capacitor, the accompanying circuit including an inductor and a switching device arranged in series; and a power generation operating point control device. The solar cells, or the solar cells and the at least one capacitor, are divided into units, of which adjacent units share one of the solar cells or one of the at least one capacitor. The power generation operating point control device is provided for each of the units, and is configured to control connection and disconnection of the switching device so as to optimize power generating capacity of the unit for which the power generation operating point control device is provided.

A non-destructive testing system for photovoltaic cells includes a non-contact electromagnetic induction device, a short-wave infrared (SWIR) camera or/and a visible-light camera, a thermal imaging device, and an image processing device. The non-contact electromagnetic induction device is configured for generating an external electric field acting on the photovoltaic cell without being in contact with the photovoltaic cell. A direction of the external electric field is parallel to that of an internal electric field of the photovoltaic cell. The SWIR camera or/and the visible-light camera is/are configured for obtaining an optical radiation distribution map within the photovoltaic cell. The thermal imaging device is configured for obtaining a thermal radiation distribution map in the photovoltaic cell. The image processing device is configured for storing and processing the optical and thermal radiation distribution maps. Non-destructive testing equipment including the above system is further provided.

A method for checking the operation of a photovoltaic module of a photovoltaic power station. The module has a positive terminal, a negative terminal and a number of solar cells, in particular thin-layer solar cells. An electric field emitted by the photovoltaic module as a result of solar radiation is measured at an exposed measurement location during the operation of the power station and the electrical voltage present between the positive terminal and the negative terminal is determined from the measured electric field. A corresponding measuring instrument has a sensor to be placed near the photovoltaic module so as to measure the electric field strength. A rod or wand may be used to position the sensor, or a robot may be configured for automatic travel on the photovoltaic module.

A method for checking the operation of a photovoltaic module of a photovoltaic power station. The module has a positive terminal, a negative terminal and a number of solar cells, in particular thin-layer solar cells. An electric field emitted by the photovoltaic module as a result of solar radiation is measured at an exposed measurement location during the operation of the power station and the electrical voltage present between the positive terminal and the negative terminal is determined from the measured electric field. A corresponding measuring instrument has a sensor to be placed near the photovoltaic module so as to measure the electric field strength. A rod or wand may be used to position the sensor, or a robot may be configured for automatic travel on the photovoltaic module.

A first switch for connection in a first circuit path between a PV panel string and an inverter in a power system, and a second switch for connection in a second circuit path across an output of the PV panel string, are normally closed and open, respectively, during non-fault operation of the power system. Both series and parallel arc faults in the power system can be extinguished by further control of the switches. Arc fault detection could be based on probabilistic frequency analysis of current or power flow measurements in the PV panel string, current or power imbalance, interruption in communications with the PV panels, or combinations of these techniques.

A space vehicle electromechanical system may employ an architecture that enables convenient and practical testing, reset, and retesting of solar panel and antenna deployment on the ground. A helical antenna winding fixture may facilitate winding and binding of the helical antenna.

Techniques for detailed monitoring and evaluation of individual subsystems within solar photovoltaic power generation systems are provided. In one aspect, a method for monitoring a photovoltaic system having at least one array of photovoltaic panels and at least one inverter system configured to convert output from the panels from DC to AC includes the steps of: obtaining sensor data from the photovoltaic system; computing an efficiency of the panels and an efficiency of the inverter system using the sensor data; computing an aging parameter for the panels using the efficiency of the panels; computing an aging parameter for the inverter system using the efficiency of the inverter system; determining whether the aging parameter for the panels or for the inverter system exceeds a predetermined threshold level; and taking action if either the aging parameter for the array or for the inverter system exceeds the predetermined threshold level.