Fault diagnosis in a grid-connected photovoltaic system by applying a signal approach

An analysis of fault diagnosis in the power conversion stage of a grid-connected photovoltaic system is developed in this work. The system under study, based on the classical dc-dc boost converter and the voltage-source full-bridge inverter, is a widely installed circuit in photovoltaic applications, which is convenient for such study. The objective is to provide methods to diagnose faults in the components of the converter, in order to achieve faster preventive or corrective maintenances. The analyses, based on the frequency spectrum of the signals, are performed under different scenarios, using different control schemes and different solar irradiances received by the photovoltaic array.