Modal Energy for Power System Analysis: Definitions and Requirements

J. Liu; F. Milano

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arXiv · 2602.17874

Modal Energy for Power System Analysis: Definitions and Requirements

J. Liu·F. Milano

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Abstract

Modal energy provides information complementary to and based on conventional eigenvalues and participation factors for power system modal analysis. However, modal energy definition is not unique. This letter clarifies the definitions and applicability of mainstream modal energy approaches, focusing on their mappings to eigenvalues and to the total system energy. It is shown that these mappings hold only under restrictive conditions, notably system normality, which limits their applicability in inverter-dominated power systems.

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J. Liu, F. Milano. 2026-02-19. Modal Energy for Power System Analysis: Definitions and Requirements. https://arxiv.org/abs/2602.17874

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