Stability Challenges in Generator-Converter Integrated Systems: A Case Study

This paper investigates the stability challenges involved in supplying DC pulse loads from AC generators via active front-end converters. As naval and maritime power systems increasingly incorporate highly dynamic, high-power loads and expand their use of converters to interface AC generation with DC distribution buses, they become more susceptible to significant voltage and frequency transients. Consequently, a comprehensive, system-level understanding of pulse-load impacts is essential. The fundamental characteristics of these pulse loads are described, along with their implications for AC bus stability. Experimental and simulation results across varying pulse amplitudes and ramp rates highlight the critical role of Phase-Locked Loop (PLL) tracking in maintaining system stability. Notably, PLL tracking errors are frequently identified as the cause of converter faults and shutdowns, underscoring the need for advanced converter control strategies to mitigate the destabilizing effects of pulsed loads and ensure reliable power delivery in mission-critical applications.