Arc Fault Detection - a Model-based Approach

Especially in electrical networks with distributed sources and a large variety of possible loads it makes sense to combine models of the components in a modular conception in order to analyze the vulnerability to arc faults and to develop reliable arc fault detection referring to the specific system characteristics. Therefore it is appropriate to analyze the small-signal behavior of the sources, the lines and the loads at a great variety of operating points and to consider the inherent characteristics in the time and frequency domain (e.g. switching frequencies of converters), if normal operation is to be distinguished from operation with arc fault and its typical broadband noise. This model-based approach allows a system-adapted design of pre-processing analogue filters in LF- or VLF-sensors and precise feature selection in pattern recognition algorithms for the purpose of arc fault detection and classification. After a generalized description the model-based methods are specified for the application field of photovoltaics and for lithium-ion-batteries.