Transient Stability Assessment of Islanded Microgrids Through Quantum Computing

Quantum Fourier Transform (QFT) is introduced in this paper, which is a quantum implementation of discrete Fourier transform (DFT) that is a cornerstone of power system dynamics analysis. The essential idea of QFT and quantum circuit implementation have been developed to compute the frequency spectrum of the transient responses of microgrids under islanded operation with droop control. QFT reduces the complexity of DFT from
$\mathcal{O}(N \log_{2} N$
) for classical computing to
$\mathcal{O}(\log_{2}^{2} N$
) for quantum computing. Thus, DFT for transient analysis can be performed exponentially faster than the fast Fourier transform in classical computers. Numerical examples of a typical networked microgrid system have tested and verified the effectiveness of QFT. It casts light on solving challenges through quantum algorithms that are hard for classical computers.