Network-Based Spectral Analysis of Power Systems with Renewable Energy Penetration

This paper studies spectral properties of power systems with renewable energy penetration from a network-based perspective. First, power network equations with renewable energy penetration and the Kron-reduced matrix are introduced. Then, the monotonicity between the number of renewable energy nodes and the eigenvalues of the Kron-reduced matrix is proved. We study the relationship between the smallest eigenvalue of the Kron-reduced matrix and voltage stability. We also report two applications of algebraic connectivity in power systems with renewable energy penetration: synchronous stability and graph partitioning. Finally, the introduced spectral properties are applied to a simple two-area system and a regional power grid in Tibet, China.