Secure faults detection for preventing fire risk in PV systems

Photovoltaic (PV) systems has been playing a key role during the last years in the evolution of electricity sector. Concerning the design issues for guaranteeing security and safety, it is particularly important to take into account that a PV plant is a "special" system of generation, in which the presence of a d.c. generator results in changings of the technical rules used for the design of electrical systems. Choices regarding the layout of the system, the grounding of the negative pole of the d.c. side and the means of protection are fundamental for the design of a PV system that takes into account the risk of fire. The subject of this article is the analysis of the relation between electrical phenomena that can occur inside of a PV system and the related means of protection (depending on the system's architecture) that can guarantee the secure fault detection and so prevent the occurrence and development of a fire.