The application provides a photovoltaic inverter system, an automatic locating method of RSDs and a fault control method thereof. The automatic locating method comprises turning off all RSDs and sampling a voltage of an output end of each RSD as a first voltage before an inverter operates; turning on any one of the RSDs and sampling a voltage of the output end of each RSD as a second voltage, determining all RSDs in a photovoltaic module string to which the RSD in a turned-on state belongs according to the first voltage and the second voltage, and repeating the above control method for any one of the RSDs outside the photovoltaic module string to which the determined RSDs belong until corresponding connection relations between all RSDs and all photovoltaic module strings are determined.

Disclosed are a test apparatus of a solar cell and a photovoltaic system including the same. A test apparatus of a solar cell according to an embodiment of the present disclosure includes an interface to receive cell information including cell efficiency, cell voltage, and cell current and a processor to perform learning based on the cell information of the solar cell and line information of a string line including the solar cell, predict an output of a solar cell module including the solar cell based on the learning, and output an output prediction value of the solar cell module. As a result, an output deviation of the solar cell module including a plurality of solar cells can be reduced.

Disclosed are a test apparatus of a solar cell and a photovoltaic system including the same. A test apparatus of a solar cell according to an embodiment of the present disclosure includes an interface to receive cell information including cell efficiency, cell voltage, and cell current and a processor to perform learning based on the cell information of the solar cell and line information of a string line including the solar cell, predict an output of a solar cell module including the solar cell based on the learning, and output an output prediction value of the solar cell module. As a result, an output deviation of the solar cell module including a plurality of solar cells can be reduced.

Embodiments of a degradation phenomenon treatment method based on a photovoltaic module and a related device are disclosed. A high frequency signal is applied to the photovoltaic module when a degradation phenomenon occurs in the photovoltaic module to protect the photovoltaic module and suppress or eliminate the degradation phenomenon. The degradation phenomenon refers to degradation of electricity generation efficiency of the photovoltaic module under effect of an electric potential. Embodiments of the degradation phenomenon treatment method and the device resolve issues associated with a declined electrical energy conversion capability and decreased electricity generation efficiency of a photovoltaic module caused by a surface polarization phenomenon, a potential induced degradation (PID) phenomenon occurring in the photovoltaic module, or both.

Embodiments of a degradation phenomenon treatment method based on a photovoltaic module and a related device are disclosed. A high frequency signal is applied to the photovoltaic module when a degradation phenomenon occurs in the photovoltaic module to protect the photovoltaic module and suppress or eliminate the degradation phenomenon. The degradation phenomenon refers to degradation of electricity generation efficiency of the photovoltaic module under effect of an electric potential. Embodiments of the degradation phenomenon treatment method and the device resolve issues associated with a declined electrical energy conversion capability and decreased electricity generation efficiency of a photovoltaic module caused by a surface polarization phenomenon, a potential induced degradation (PID) phenomenon occurring in the photovoltaic module, or both.

A method for electrically characterising a cut photovoltaic cell, includes measuring the feature I-V of the uncut cell; cutting the cell into a plurality of sub-cells; measuring the feature I-V of each sub-cell not electrically connected to the other sub-cells; measuring the feature I-V of a set comprising all the sub-cells connected in parallel; determining, on the basis of the measured features I-V, performance parameters of the uncut cell, of each sub-set and of the set; computing, for each sub-cell, the difference between the value of the performance parameters of the sub-cell and that of the performance parameter of the uncut cell; and computing the difference between the value of the performance parameter of the set and the value of the performance parameter of the uncut cell.

A method for electrically characterising a cut photovoltaic cell, includes measuring the feature I-V of the uncut cell; cutting the cell into a plurality of sub-cells; measuring the feature I-V of each sub-cell not electrically connected to the other sub-cells; measuring the feature I-V of a set comprising all the sub-cells connected in parallel; determining, on the basis of the measured features I-V, performance parameters of the uncut cell, of each sub-set and of the set; computing, for each sub-cell, the difference between the value of the performance parameters of the sub-cell and that of the performance parameter of the uncut cell; and computing the difference between the value of the performance parameter of the set and the value of the performance parameter of the uncut cell.

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 Δt.sub.1 and the power flow P is suppressed in an inactive time window with the second period Δt.sub.2. Via detection of an input current I.sub.in flowing at the input and/or an input voltage U.sub.in applied to the input and comparison of values of the input current I.sub.in and/or input voltage U.sub.in detected in the inactive time window with a current threshold value I.sub.TH or a voltage threshold value U.sub.TH an arc presence criterion is signaled if the input current I.sub.in detected in the inactive time window falls below the current threshold value I.sub.TH and/or the input voltage U.sub.in detected in the inactive time window does not exceed the voltage threshold value U.sub.TH. The application also describes a circuit arrangement for detecting an arc and a photovoltaic (PV) inverter including such a circuit arrangement.

In one respect, disclosed is an in-situ current-voltage (I-V) measurement device for photovoltaic modules in a photovoltaic array, comprising a variable load, wherein the variable load is configured to be connected in parallel with a module, wherein the module is connected in series with at least one other module in a string, such that the module supplies current simultaneously to the string and to the variable load, and wherein the variable load is controlled by a controller, and wherein the controller is configured to shift an I-V operating point of the module, based at least upon varying the variable load.

In one respect, disclosed is an in-situ current-voltage (I-V) measurement device for photovoltaic modules in a photovoltaic array, comprising a variable load, wherein the variable load is configured to be connected in parallel with a module, wherein the module is connected in series with at least one other module in a string, such that the module supplies current simultaneously to the string and to the variable load, and wherein the variable load is controlled by a controller, and wherein the controller is configured to shift an I-V operating point of the module, based at least upon varying the variable load.