DC Series Arc Fault Detection and Extinguishing With Modulation Algorithm of Non-Inverting Buck-Boost Converter for PV Applications

Power generation using a photovoltaic (PV) system is increasing to achieve the carbon neutrality. Module-level power electronics (MLPEs) can optimize power generation for each PV panel. However, it increases the possibility of DC series arc fault condition between the PV panel and MLPEs. The broken and loose connector and damaged cable can induce a DC series arc fault condition. Previously, frequency domain analysis using PV current, such as Fourier transform and wavelet transform, was widely employed for DC series arc fault detection. It requires the auxiliary device to detect the arc failure, which degrades the cost-effectiveness of PV systems. In addition, they cannot achieve the fault detection and extinguishing in the same time. This paper proposes a modulation algorithm of non-inverting buck-boost converter (NIBBC) to achieve the DC series arc fault detection and extinguishing. The proposed method uses the characteristics of PV, NIBBC, and arc fault to classify the normal and arc fault conditions. The operational principle is analyzed to design the modulation method according to operating modes. The 800-W prototype NIBBC is used to verify the performance of series arc fault detection and extinguishing.