Problems such as low voltage and big line loss have long existing in the power grid in rural areas of China. In recent years, some province and cities have improved voltage and reduced line loss by installing SVG at substations in rural power grids, and the effect is remarkable.With great compensation capacity and a good variety of modes of compensation, SVG is sure to replace old reactive compensation devices in rural power grid in future, which requires evaluation and analysis of SVG reliability so as to guarantee safety and stability of the power grid. However, now no research or analysis has been made in China on SVG reliability in rural power grids, which affects wide promotion of SVG in rural power grids.Under the background of Liaoning Power Grid 10kV/±5Mvar Chain SVG, this paper analyzes the reliability of k/n (G) system model of SVG master circuit structure, improving the accuracy of system reliability estimation. The estimation matches the operation outcome, thus providing data basis for the feasibility of SVG’s wide application in rural power grid in future.

In view of a large number of distributed generators penetrated into distribution network, an improved hierarchical island operation was proposed to make the DG play the role as backup power supply in the service restoration of the distribution network; As the renewable distributed generators was strongly advocated, A new mathematical model was proposed to make full use of them. The service restoration problem is a constrained multi-objective optimization problem, a new algorithm which was the combination the heuristic algorithm and multi-agent evolutionary algorithm was proposed, it improved the multi-agent evolutionary algorithm with the Niche technologies to ensure the variety of the populations in the post-optimization and used the adaptive updating strategy to improve the convergence speed. The results of a case show feasibility and correctness of the model and the algorithm.