Patent ID: 9553215
Date: 2017-01-24
CPC Classifications: H01L,H02S,Y02E

Claim:
1. A method for recognizing faults in a photovoltaic system, comprising the steps: determining a first parameter derived from a first output voltage of the photovoltaic system at a first time point in a first operating state of the photovoltaic-system for determining a starting condition during an initialization process, determining a second parameter derived from a second output voltage of the photovoltaic system at a second time point, when a weather analysis for establishing a sun radiation above a threshold leads to a positive result and there is a second operating state comparable with the first operating state, wherein the weather analysis is performed by using output data from the inverter and without using a light sensitive sensor or a radiation sensor, and wherein the weather analysis is considered to be positive if a power output of the inverter is above 15% of the respective nominal power, determining a deviation between the first and second parameter and outputting an error message when the deviation exceeds a predeterminable threshold, wherein each of the first parameter and the second parameter is the ratio between the maximum power point voltage and the open circuit voltage of the photovoltaic system.