Experimental performance and analysis of standalone self-excited induction generators considering different fault variations and power quality

Abstract Self-excited induction generators (SEIGs) are suitable for renewable energy applications due to their simple construction, low cost, and minimal maintenance requirements. SEIGs are superior to traditional synchronous generators in edge-of-grid pico-hydro systems because they offer inherent self-excitation and do not require external excitation. This research studies the power quality performance of SEIGs by analyzing voltage regulation, frequency variation, total harmonic distortion (THD), and power factor (PF) under varied rotor speeds and excitation capacitance. The behavior of SEIGs under abnormal operating conditions is also examined through extensive fault analysis, including open circuit faults and short circuit faults such as single line-to-ground (LG), line-to-line (LL), double line-to-ground (LLG), three-line (LLL), and three-line-to-ground (LLLG) faults. These source parameters variation and fault condition are performed in hardware setup and the results are executed. Experimental results reveal that terminal voltage and current THD increase with increasing speed and excitation capacitance. Depending on the load and capacitor configuration, the SEIG can tolerate both single- and double-conductor open circuit faults. The generator can withstand LG faults up to 40 % load with delta connected excitation capacitors, but other short-circuit faults result in stalling. These findings support SEIGs applicability for pico-hydro power production.