Control Of Reactive Power And Voltage Of The Regional Power Grid And R&D Of The System

The main objectives of var/voltage control to a regional power grid are to control the voltage and power factor and to reduce the power losses. The main control devices are transformers and capacitors. With the expansion of the power grid and the improvement of the electricity requirements of the users, the traditional manual control means can’t meet people’s requirements, to develop the AVC system is imperative. For these questions of var/voltage control, this paper develops the AVC system with the combination of state estimation and reactive power estimation, and verify the reliability of the program with a practical example.By analyzing the status of the reactive power optimization and the development of the AVC system at home and abroad, the paper conclude the problems in the AVC system, the data is not accurate enough and the instructions are not reliable. The data problem can be solved with state estimation. We can calculate the estimated data that can reflect the actual condition of the power grid with the redundant data and the state estimation algorithm. The improvement of the data accuracy can improve the accuracy of the reactive power optimization and can also improve the reliability of the AVC system. Another reason of the low reliability of the AVC system is the changes of the grid load. To avoid the frequent actions of the reactive power compensation equipments, the AVC system won’t sent the instructions immediately. It will sent the final instructions by comparing two instructions. If the two instructions are different, that indicates that the grid load have changes, we can’t send the instructions. If the two instructions are the same ones, we can send the instructions.To prove the validity of the optimization method, the paper calculate the subsystem of the Binzhou grid. This paper calculate the data from SCADA system with state estimation algorithm. And with the estimate data, we can execute the reactive power optimization. Compare the grid losses and the voltage quality, we can find the reactive power optimization can apparently improve the grid losses and voltage quality.In this paper we develop a AVC system according the algorithm and Binzhou actual grid. The AVC system improve the accuracy of the grid data and can give the reliable instructions. It can also achieve the goal of reducing the grid losses and extend the life of reactive power compensation equipments.The AVC system has good scalability. We can change the substation or add/delete a substation by the editing client. This can adjust the development of the grid.According to the commissioning in Binzhou power grid, we can see that the AVC system can improve the power quality, reduce the power losses and improve the work efficiency. It has great significance for the development of the grid.