Microscopic fluctuations in power-grid frequency recordings at the sub-second scale

Benjamin Schäfer; Leonardo Rydin Gorjão; G. Cigdem Yalcin; Ellen Förstner; Richard Jumar; Heiko Maass; Uwe Kühnapfel; Veit Hagenmeyer

arXiv · 2208.06379

Microscopic fluctuations in power-grid frequency recordings at the sub-second scale

Benjamin Schäfer·Leonardo Rydin Gorjão·G. Cigdem Yalcin·Ellen Förstner·Richard Jumar·Heiko Maass·Uwe Kühnapfel·Veit Hagenmeyer

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Abstract

Complex systems, such as the power grid, are essential for our daily lives. Many complex systems display (multi-)fractal behavior, correlated fluctuations and power laws. Whether the power-grid frequency, an indicator about the balance on supply and demand in the electricity grid, also displays such complexity remains a mostly open question. Within the present article, we utilize highly resolved measurements to quantify the properties of the power-grid frequency. We show that below 1 second, the dynamics may fundamentally change, including a suddenly increasing power spectral density, emergence of multifractality and a change of correlation behavior. We provide a simplified stochastic model involving positively correlated noise to reproduce the observed dynamics, possibly linked to frequency dependent loads. Finally, we stress the need for high-quality measurements and discuss how we obtained the data analyzed here.

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Benjamin Schäfer, Leonardo Rydin Gorjão, G. Cigdem Yalcin, Ellen Förstner, Richard Jumar, Heiko Maass, Uwe Kühnapfel, Veit Hagenmeyer. 2022-07-07. Microscopic fluctuations in power-grid frequency recordings at the sub-second scale. https://arxiv.org/abs/2208.06379

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