Photovoltaic array fault detection based on a new model of series equivalent resistance

Abstract To address the difficulty of detecting photovoltaic array faults using photovoltaic array model parameters in photovoltaic power stations, a photovoltaic array fault detection method based on a new series equivalent resistance model is proposed. In this method, first, a mathematical model of the series equivalent resistance of a photovoltaic module is established based on the single-diode model of the photovoltaic module using the characteristics of this module when it operates at the maximum power point, short circuit and open circuit. Second, a new model of the series equivalent resistance of the photovoltaic array is obtained based on the mathematical model of the series equivalent resistance of the newly constructed photovoltaic module, and a series equivalent resistance fault detection model is proposed under short-circuit, degradation and shadow faults. Finally, the proposed new model of the series equivalent resistance of photovoltaic arrays is compared with three existing mathematical models to verify its validity and accuracy. Simultaneously, the series equivalent resistance fault detection model is verified in the case of short-circuit, degradation and shadow faults of photovoltaic arrays.