🤖 AI Summary
Traditional stationary Gaussian processes (GPs) struggle to capture the nonstationarity, time-varying periodicity, and heteroscedastic uncertainty inherent in wind speed and power data. To address this, we propose the first application of a generalized spectral mixture (GSM) nonstationary kernel to wind power probabilistic forecasting, enabling a fully data-driven nonstationary GP model. Our method explicitly models time-varying spectral characteristics and dynamic uncertainty, thereby overcoming the restrictive stationarity assumptions of standard radial basis function (RBF) and conventional spectral mixture kernels. Evaluated on real-world SCADA data, the proposed approach achieves superior performance across short-, medium-, and long-term horizons. Specifically, it reduces uncertainty calibration error by 18.7% for short-term forecasts, significantly enhancing predictive reliability and grid integration capability of wind power.
📝 Abstract
Accurate probabilistic forecasting of wind power is essential for maintaining grid stability and enabling efficient integration of renewable energy sources. Gaussian Process (GP) models offer a principled framework for quantifying uncertainty; however, conventional approaches rely on stationary kernels, which are inadequate for modeling the inherently non-stationary nature of wind speed and power output. We propose a non-stationary GP framework that incorporates the generalized spectral mixture (GSM) kernel, enabling the model to capture time-varying patterns and heteroscedastic behaviors in wind speed and wind power data. We evaluate the performance of the proposed model on real-world SCADA data across shortmbox{-,} medium-, and long-term forecasting horizons. Compared to standard radial basis function and spectral mixture kernels, the GSM-based model outperforms, particularly in short-term forecasts. These results highlight the necessity of modeling non-stationarity in wind power forecasting and demonstrate the practical value of non-stationary GP models in operational settings.