Keerati Chayakulkheeree2551-02-222551-02-222550-10-25http://dspace.spu.ac.th/handle/123456789/817This paper introduces an application of distributed slack bus power flow to competitive electricity supply industry (ESI). The participation factors of the generators are obtained by the weighted average of AGC accepted quantities in the ancillary services market. The results shows that the proposed method can satisfactory represent the system behavior that all generators are response to power imbalance. In addition, the proposed method results in the better justified AGC setting in competitive electricity market than that of using single slack bus power flow.en-USElectricity Supply IndustryAncillary ServicesArticle