Method for Recognizing Theft of a PV Module and a Failure of a Bypass Diode of a PV Module, Corresponding PV Sub-Generator Junction Box, PV Inverter, and Corresponding PV System

摘要

A method for recognizing the theft of at least one photovoltaic module of a PV system. The PV system comprises at least one string of serially connected PV modules for supplying a field voltage, where the at least one string is connected in parallel and the PV modules each have a plurality of serially connected PV cells. In addition, bypass diodes connected in an anti-parallel manner are provided for protecting the PV cells. During a non-charging operation, i.e., the evening and at night, a test voltage that is negative relative to the field voltage is connected to the at least one PV string to adjust a test current through the bypass diodes. A theft message is automatically output when at least one of the test current and the test voltage significantly change.