Reactive Power Optimization Research For 500kV Substation Based On Load Prediction

Voltage is one of the three index of the power grid on the network security and stability. The power grid of Jiangsu province, is the largest provincial power grid in China, and the 500kV substation is the monitor and anchor of the grid voltage, so it is very important and it has practical significance to ensure the voltage stabilization and the reactive power balance of the 500kV substation.In order to optimize the voltage and the reactive power of the grid, firstly, It need to forecast the load of the specified day. Under the conditions of comparing various loading forecast method, the paper using an artificial neural network method to forecast load and voltage. Secondly, the objective function is being set up, it makes the quality of the bus voltage and operating times of the equipment as constraints and it aims at the line and transformer losses as the target. The estimated load is firstly segmented, and then to confirm the electric transducer tap’s position after calculate the objective function in the segment lastly, it segmented the predicted reactive power, and calculated objective function in the segment to determine the capacitor bank switching scheme.Finally, the no power optimization scheme is applied to a 500kV substation, the calculation results show that voltage and reactive power optimization method proposed in this paper can effectively improve the level of reactive power optimization, reduce network losses, achieve significant results on the technical and economic.