Voltage Drop Compensation Control Method for High-Rate Discharge LBESS Under Variable Frequency Conditions

Lithium battery energy storage system(LBESS) has been widely used in high-power requirement occasions due to its advantages of high specific energy and high specific power. However, under different operating conditions, for high power loads, the output voltage of LBESS will drop due to its own high rate of discharge. For this purpose, a adaptive active disturbance rejection control (A-ADRC) with adaptive adjustment of controller gain is proposed to realize the fast compensation of output voltage under various operating conditions. In addition, the output current of the LBESS generates low-frequency fluctuations due to the influence of the modulation strategy of the secondary inverter and the load imbalance. In order to reduce the output current ripple amplitude of the LBESS, a dynamic notch filter is introduced into the active disturbance rejection controller to suppress the output current ripple under variable frequency conditions. Finally, the effectiveness of the proposed method is verified by Matlab/Simulink simulation.