The invention discloses a
power grid structure optimization method capable of reducing
transmission loss and relieving
voltage sag, comprising the following steps: first, acquisition of optional operation schemes of a
power grid: acquiring all optional operation schemes according to the condition whether parallel capacitors are installed on respective buses in a to-be-optimized
power grid, capacity of the installed parallel capacitors, the condition whether switches are installed on respective branches, and states of the installed switches; second, feasibility determination; third, determination of
transmission loss of the power grid: screening operation schemes with
low transmission loss; fourth, determination on influence of
voltage sag: 401, calculating
voltage sag evaluation indexes of the power grid, 402, determining a configuration scheme with
low voltage sag influence; and fifth,
investment cost determination: 501, calculating
investment cost, 502, determining an optimized operation scheme. The power grid structure optimization method disclosed by the invention has the advantages of simple method steps, reasonable design, convenience for implementation, good using effect, reduced
transmission loss, relieved
voltage sag, economical configuration of the parallel capacitors and capability of realizing safety operation and economical operation of the power grid.