抄録
A large number of Dispersed Generations (DGs) are expected to be installed in distribution systems. Therefore the state estimation is important problem for stable and reliable system operation. However, it is difficult to estimate the total power of DGs connected to a load-side system from a metering spot on the distribution line because at the metering spot only a sum of the active-power from various loads and DGs can be measured. In this paper, we propose an estimation method for unknown DG-outputs connected to a distribution system. This method enables to estimate DG-outputs by analyzing a power flow data measured at one spot using independent component analysis (ICA). The estimation by ICA needs the same number of observations as estimations. However the observation spot is extremely limited in existing distribution system. So we propose an estimation method which enables to estimate DG-outputs and load-changes from only an observation by using known information of load power and a priori knowledge of insolation.