Balancing control of PV power and dispersed generators using H∞ control

Recently, dispersed generators have been installed in distribution network to supply power to commercial facilities. Renewable energy generation contains output power fluctuations and distributed generator produces sluggish response for power demand. In order to overcome these problems, an ultra capacitor energy storage system is used for compensating instantaneous power imbalance. However, large capacity ultra capacitor energy system results increasing facility cost. In addition, PPSs (Power Producer and Supplier) that own these generators are supposed to achieve 30-minute balancing control for stable supply of electric power. This paper proposes the control system to achieve both 30-minute balancing control and interconnection point power flow control by using fuel cell and ultra capacitor based on H_∞ control theory. Besides, the remaining storage energy of the ultra capacitor is controlled to be constant to maintain compensation capability. The effectiveness of the proposed control system is verified by using simulation results.