Fault identification scheme for solar photovoltaic array in bridge and honeycomb configuration

Large solar power plants are installed in many countries, and they are connected to an electrical grid thereby providing an alternative to conventional energy sources. Photovoltaic cells are using solar energy directly and convert it into electrical power. To ensure there liable and safe operation of PV arrays, it is very essential to diagnose faults in PV arrays. Traditional fault detection devices are used for detecting line-to-line fault and open-circuit faults, if the magnitude of fault current defined as per international standards exceeds the threshold value. Due to several aspects like low irradiance condition, minimal fault mismatch, and active maximum power point trackers which minimizes the magnitude of fault current thereby resulting in fault identification becoming much more difficult. In case a fault in a PV array is not identified and the fault persists for a very long duration, it results in reliability issues and also it may lead to severe fire hazards. Hence, it is essential to identify the fault in a timely manner, and also localization is very much essential for sustainable power generation. This paper proposes new fault identification scheme for solar PV arrays connected in bridge and honeycomb configuration, and this method is capable to detect line-to-line fault and open-circuit faults with a minimum number of sensor requirement and also irrespective of the detection challenges. For real time, validation testing is carried out in a PV array, and the power gain due to the identification of line-to-line fault and line-to-ground fault is also investigated.