This paper proposes an optimization and dispatching method of dynamic reactive power in distribution network with distributed generators (DGs)

in order to solve the space-time coupling. Firstly

the optimization of the static power flow is calculated and the pre-action time table is made according to the increment of capacitor switching capacity. Secondly

the dynamic subarea of the distribution network is calculated

and the load data are managed according to the results of the partitioning and the pre-action time table. Then

aiming at the least system energy loss the dynamic reactive power optimization is made in which the capacitor switching capacity is the controlled variable

and the capacitor switching scheme is obtained. Finally

the reactive power generation of the DGs in the grid is optimized

and the related scheme is got. This paper takes the IEEE 33-bus network as an example to simulate

and contrasts with the existing methods to confirm the rationality and effectiveness of this method

and proves that this method makes less energy loss than the existing methods.