Title |
Frequency Control Method of Grid Interconnected Microgrid Operating in Stand Alone Mode |
Authors |
채우규(Chae, Woo-Kyu) ; 이학주(Lee, Hak-Ju) ; 박중성(Park, Jung-Sung) ; 조진태(Cho, Jin-Tae) ; 원동준(Won, Dong-June) |
DOI |
https://doi.org/10.5370/KIEE.2012.61.8.1099 |
Keywords |
Microgrid ; Droop ; BESS ; Battery ; Cooperative control ; Frequency control |
Abstract |
Microgrid is a new electrical energy system that composed of various generators, renewable energy, batteries and loads located near the electrical customers. When Microgrid is interconnected with large power system, Microgrid don't need to control the frequency. But in case of the outage or faults of power system, Microgrid should control the frequency to prevent the shutdown of Microgrid. This paper presents the frequency control methods using the droop function, being used by synchronous generators and EMS(Energy Management System). Using droop function, two battery systems could share the load based on locally measured signals without any communications between batteries. Also, we suggest that EMS should control the controllable distributed generators as P/Q control modes except batteries to overcome the weakness of droop function. Finally we suggest the two batteries systems to prolong the battery's life time considering the economical view. The validation of proposed methods is tested using PSCAD/EMTDC simulations and field test sites at the same time. |