ABSTRACT This paper presents the application of the Harrow‐Hassidim‐Lloyd (HHL) algorithm and its simplified quantum circuit to distributed state estimation in power grids. The proposed circuit comprises three main components: quantum phase estimation, controlled rotation, and inverse quantum phase estimation. Each component was implemented using quantum gates, with a focus on reducing circuit complexity within each block. This simplification lowers the number of quantum gates and control bits needed, thereby enhancing the computational efficiency of distributed state estimation. To evaluate the feasibility of the proposed method, simulations were conducted on the IEEE 30‐bus system. The computation performance was assessed using trace distance, circuit size, and output accuracy. The results show that the proposed approach successfully tackles distributed state estimation in a power grid, underscoring its potential as a practical quantum computing solution for this field.
Huang et al. (Thu,) studied this question.