In Korean power system, 376 MW of battery energy storage system (BESS) functions as primary control reserve. The current total requirement of primary control reserve is 750 MW, which is procured by 376 MW of BESS and 374 MW of conventional generators. The BESS installed in the Korean power system can supply its energy for 10 min after loss of generators. If all the energy of the BESS is supplied during the system frequency restoration, this can cause a shortage in primary control reserve. Therefore, a new approach for reserve procurement is required to cope with the shortage in primary control reserve in case the second contingency might happen. Pumped storage hydro generators are good candidates for the additional reserve sources. In this paper, we propose a methodology for procuring additional primary control reserve considering their availability varying in real time and droop characteristics. In the case study, the effect of the proposed methodology is verified through a dynamic simulation.
Read full abstract