Bus load modelling and forecasting

Knowledge of the individual bus loads in electric distribution systems is important for planning and systems operation. Knowledge of the actual loading provides an improved decision basis for system expansion, ant the operation of distribution systems requires a large number of planned or forced switching operations, for which it is necessary to know the hourly load behavior at the substation level. The individual loads are calculated by using estimation methods to determine the future load behavior on the basis of typical past measurements. The mathematical problem is formulated as a linear model relating load measurements with normalized load curves (state variables) for the individual customer groups. The linear model is given by a priori knowledge of the normalized load curves and the fixed load composition at the substation level. Used together with nonlinear models describing external influences, such as temperature, it is possible to predict the load behavior in any substation, based on the estimates of the normalized load curves.>