Real-Time Fault Diagnosis in Photovoltaic Based DC Microgrids Using Modified Change Detection Filter

In DC microgrids, quick fault detection and isolation is still a key challenge in microgrid protection. This paper proposes a new approach using a modified change detection filter (M-CDF) to detect and isolate faults in multiple photovoltaic-based DC microgrids. The proposed microgrid is subjected to various faults, and corresponding data is collected from the DC bus. The voltage signal is then processed through the M-CDF, which uses a reference window to compare with other windows in a sliding pattern to detect sudden changes or faults based on the detection threshold. Simultaneously, it also isolates the fault section from the healthy section by sending a trip signal to the circuit breaker. To obtain remarkable results in terms of detection for both low and high-magnitude faults, M-CDF is further subjected to Teager energy (TE) and it is named TE-CDF. As a result, it accurately detects the faults even when low-magnitude faults occur by exhibiting large magnitudes. Further, to evidence the superiority, applicability, and simplicity of the proposed approach (i.e., TE-CDF) is validated on a hardware test bench through dSPACE DS 1104 embedded processor, and obtained results are compared over benchmark techniques.