earticle

영어

The uncertainty and fluctuation brought by distributed type of intermittent power generation in micro grid bring huge challenges to power quality of micro grid in isolating operation and power control in parallel operation. Nevertheless energy storage is able to well solve this problem. Hybrid energy storage integrates the respective advantages of storage battery and supercapacitor to have improved the performance of energy storage system. Service life of storage battery is tightly related to its charging/discharging times and problem of frequent charging/discharging storage battery still exists in current hybrid energy storage technology. In this paper, it respectively puts forward control strategies for storage battery and supercapacitor. As to control strategy for storage battery, it uses double-layered control strategy, namely, single loop control and power hysteresis control, to feedback low-frequency fluctuation of power and reduce charging/discharging frequency of storage battery. As to control strategy for supercapacitor, it uses inner loop current with power to control voltage in outer loop so as to feedback high-frequency fluctuation of power and it is able to well maintain stability of DC bus voltage. Simulation results suggest the validity of aforesaid control strategies.