SOC estimation of battery systems for ultra-large capacity battery-powered ships under multiple constraints

With the increasingly stringent environmental regulations and the increasing progress of energy storage power electronics technology, battery power, as one of the green ship power technologies, has become a current research hotspot. The ultra-large capacity battery system generally has the disadvantages of short cycle life, easy reduction of capacity influenced by external factors and high replacement cost. In order to make better use of battery energy, it is necessary to accurately estimate the size of the battery pack’s charge state and restrict it to prevent overcharge and overdischarge. Comparing the adaptive untracked Kalman filter algorithm with the extended Kalman filter algorithm to estimate the SOC reliability and error size of the energy storage element, it is proved that the SOC estimation results obtained by the adaptive Kalman filter algorithm are more reliable, which lays a foundation for the DC bus voltage stability control strategy.