Research on active equalization algorithm of lithium battery based on frequent item statistics and transferred power

Aiming at the problem that precise equalization can not be carried out due to the poor consistency of the single battery, an active equalization method based on frequent item statistics and transfer power is proposed. The equalization basis is transformed from open circuit voltage, operating voltage, and state of charge (SOC) to transfer power. The active equalization topology is constructed with a single switched capacitor as the core. The data stream frequent pattern mining technology is introduced to count the transfer power summary information during the charge and discharge cycle of the single battery. The order and number of battery equalization are intelligently selected by the equalization algorithm. The capacitance size, voltage noise, transfer power summary information extraction process, and equalization strategy comparison simulation experiments were carried out. The proposed active equalization method can accurately select the number and sequence of battery equalization cells, minimize the back-and-forth flow of energy, effectively prolong the time of a single charge and discharge cycle, and improve the efficiency of the active equalization algorithm.