The improved reactive power optimization algorithm and model considering power grid partitioning is presented in this paper.The upper and lower power grid is classified more clearly;reactive optimization solution of the whole systems is obtained by the voltage and power of interface nodes through upper and lower interation.And the convergence criterion of iterative algorithm is also given.At last

it is shown through application of the proposed algorithm at a certain regional power grid that partition iteration is much better than the whole grid in the aspects of optimization quality

convergence reliability and time.