It is indispensable to forecast accurately the very short-term load demand to avoid undesirable disturbances in power system operations which deteriorate economical generations. The authors have so far developed a short-term forecasting method by using Local Fuzzy Reconstruction Method, a variant of the methods based on the chaos theory. However, this approach is unable to give accurate forecasting results in case where load demand consecutively exceeds the historical maximum or is lower than the minimum because forecasting is performed by the historical data themselves. Also, in forecasting holidays in summer, forecasting result of weekdays might appear due to similar demand trend.
This paper presents novel demand forecasting methods that are able to make accurate forecasts by resolving the above mentioned problems. First, the new method improves the accuracy by extrapolating forecasted transition from the current point. Secondly, to eliminate miss forecast which may be occurred on holidays in summer, historical data are labeled by the information of the day of the week to distinguish similarly behaved weekdays’ load patterns.
The proposed methods are applied to 10, 30, and 60 minutes ahead demand forecasting, and the accuracy is improved 10% to 20% compared with the method previously proposed.