Abstract
The combined method for interval forecasting (CMIF) is proposed for improved real-time prediction of wind speed uncertainty to facilitate wind turbine operation and power grid dispatching. Time-varying filtering for empirical mode decomposition and phase space reconstruction are used to decompose and reconstruct the original wind speed sequence to solve chaotic phenomena and eliminate noise. Statistical and machine learning models are considered as candidates, and models with excellent performances are selected. Finally, the selected models are combined by a multi-objective optimizer to obtain the final prediction. Experiments were performed using data from the Gansu wind tower, and the results showed that CMIF improved the accuracy of the predicted wind speed interval by 1.07-55.37% compared with single models. The prediction interval had a narrow width while maintaining a high coverage rate, which facilitated accurate quantification of the wind speed uncertainty.