Hardware-in-the-Loop Model Validation of Charging Capacitors With Multipulse Rectifiers for High Rep-Rate Shipboard-Pulsed DC Loads

Future U.S. Navy shipboard power architectures will integrate new ac and dc rep-rate pulsed loads that must be reliably energized. Delivering power to these loads typically requires charging large capacitor banks in a highly transient manner that causes a lot of stress on the ship's prime power sources. Controlled multipulse rectifiers have been proposed as a direct solution to charging these capacitor banks and may eliminate the need for large passive filter components. Though multipulse rectifiers are well documented in the literature, there is little to no published work that studies the impact of multipulse rectifiers have on power quality when loaded by large capacitive loads in high rep-rate profiles. It is desired that MATLAB/Simulink models be developed for deployment on the OPAL-RT real-time simulator for predicting power quality in existing ship power system models. This paper discusses the development of 6-, 12-, and 24-pulse models based on equivalent hardware at a low voltage and power rating for study. Experiments are performed on the hardware equivalent systems, and data are collected. The data are then compared with the simulation results in the time and frequency domain for model validation. Issues encountered when modeling the phase-shifting transformers are discussed, and recommendations and cautions are proposed for future work.