Method for Controlling Individual Photovoltaic Modules of a Photovoltaic System

A method for controlling individual PV modules of a PV system, the method comprising the steps of:

• a) providing a PV string that includes a plurality of PV modules;
• b) providing a control device that includes a corresponding plurality of control units;
• c) associating one control unit with a corresponding one PV module of the plurality of PV modules, wherein each control unit measures the voltage curve and/or the current of the corresponding one PV module;
• d) if the voltage of the one PV module increases from an operating voltage to an open-circuit voltage, or the voltage decreases from the open-circuit voltage to the operating voltage, or the current in the string drops below a reference value, activating the control unit of the one PV module, wherein activation of the control unit results in a drop of the overall voltage of the at least one string to a value that is not hazardous to humans.