ЗАБЕЗПЕЧЕННЯ СТАТИСТИЧНОЇ ОДНОРІДНОСТІ ДОБОВИХ ГРАФІКІВ ЕЛЕКТРИЧНОГО НАВАНТАЖЕННЯ ЕНЕРГОЄМНИХ ПІДПРИЄМСТВ ПРИ КОРОТКОСТРОКОВОМУ ПРОГНОЗУВАННІ НАВАНТАЖЕННЯ ЕНЕРГОСИСТЕМИ
The efficiency of the Ukraine Interconnected Electrical Power System (IEPS) operating modes scheduling essentially depends on short-term electric load forecasting results. The increase in number of factors significantly influencing on electric load contribute to improve the accuracy and reliability results of forecasting. However their certainty is essential. The energy-consuming enterprises contribute a great share into the electricity consumption of IEPS of the Ukraine. Analysis of the daily schedules of their electrical load over a long time period showed the availability of anomalous data caused by the system of data gathering, transmission and the basic information processing failures. Also the anomalous data appearance is dependent on abrupt changes of the operating conditions enterprises due to the technological and economic factors. The paper presents a two-stage statistically correct algorithm of the anomalous measurements discarding and the energy-consuming power enterprises missing data replacement in the total electric load sample. Besides, the anomalous values are subdivided depending on their character and continuance. At the first stage of the verification the sample essential anomalous values identification and missing data replacement are performed using linear interpolation. At the second stage the unobvious anomalous values are excluded by means of the preliminary discarding of the sample trend component by piecewise polynomial approximation. Single anomalous values replacement is performed with the aid of the linear approximation, but the group ones are replaced taking into account their change character. At the both stages the determination of the statistical characteristics, the type of data distribution low (Gaussian, unimodal or arbitrary) and the discarding are performed by means of Chebyshev criterion. The accuracy and unambiguous character of the verification results were controlled by a great number of calculations based on data of daily electric load schedules for annual period of time for “Dniprooblenergo” energy-consuming enterprises. References 5, figures 6, table.