Patent ID: 8471574
Filing Date: 2013-06-25
Classification: G01R,H02S,Y02E

Abstract:
1. A measuring method for determining a drop in an output of a PV (PhotoVoltaic) unit within a photovoltaic system comprising a plurality of electrically parallel-connected PV units, whereby each PV unit is removable from the parallel circuit via a switching device and a total current measuring device for measuring the total current through all PV units of the parallel circuit, the method comprising: i) determining a summed direct current of all parallel connected PV units with a total current measuring device and storing a value thereof; ii) removing one of the PV units from the parallel circuit via the switching device assigned to it; iii) determining the summed direct current through all PV units, with the exception of the removed PV unit, with the total current measuring device and storing a value thereof; iv) closing a switch of the removed PV unit such that the PV unit is once again integrated into the parallel circuit; v) performing steps ii) to iv) for all PV units in the parallel circuit; and vii) providing the stored current values to an evaluation unit.