Abstract In view of the phenomenon of long power supply radius, low power factor, large line loss, and poor voltage quality in the single-radiation power supply mode of reactive voltage control in Jiangsu area, this paper studies and establishes a set of three-level coordinated control of reactive voltage in distribution network The system can realize the three-level coordinated control of the substation, transmission line and distribution voltage reactive power compensation device according to the actual short-term load changes, which can effectively solve the high voltage, ground voltage and three-phase imbalance existing in the power grid in Jiangsu. The voltage qualification rate is increased to 100%; in addition, the system can also provide analysis of the power quality status of the distribution network, combined with the analysis and comparison of the results of power quality optimization governance, to achieve scientific results evaluation, for the energy-saving control of the power grid and power quality governance Provide reference to provide basic data for power grid construction.