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arXiv · 2301.04551

Non-linear, bivariate stochastic modelling of power-grid frequency applied to islands

Ulrich Oberhofer·Leonardo Rydin Gorjão·G. Cigdem Yalcin·Oliver Kamps·Veit Hagenmeyer·Benjamin Schäfer
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Abstract

Mitigating climate change requires a transition away from fossil fuels towards renewable energy. As a result, power generation becomes more volatile and options for microgrids and islanded power-grid operation are being broadly discussed. Therefore, studying the power grids of physical islands, as a model for islanded microgrids, is of particular interest when it comes to enhancing our understanding of power-grid stability. In the present paper, we investigate the statistical properties of the power-grid frequency of three island systems: Iceland, Ireland, and the Balearic Islands. We utilise a Fokker-Planck approach to construct stochastic differential equations that describe market activities, control, and noise acting on power-grid dynamics. Using the obtained parameters we create synthetic time series of the frequency dynamics. Our main contribution is to propose two extensions of stochastic power-grid frequency models and showcase the applicability of these new models to non-Gaussian statistics, as encountered in islands.

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Ulrich Oberhofer, Leonardo Rydin Gorjão, G. Cigdem Yalcin, Oliver Kamps, Veit Hagenmeyer, Benjamin Schäfer. 2023-01-11. Non-linear, bivariate stochastic modelling of power-grid frequency applied to islands. https://doi.org/10.1109/powertech55446.2023.10202986

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