Design and Test of Overvoltage Monitoring Device for 500kV Smart Substation

With the continuous economy development, the requirements for the stability and reliability of power system are much higher. In order to improve the perception ability of equipments’ states, the construction of Smart Substation is rapidly carried out. Based on the actual needs of 500kV Smart Substation, this paper designs the overvoltage monitoring device based on series connected capacitor, and analyzes the key factors such as the measurement accuracy of voltage transformer with series connected capacitor and the influence of cable inductance on the measurement signal. Based on the actual parameter of 500kV Dinggong substation, the appropriate design parameters of monitoring devices are selected, and the measurement accuracy is verified on the worksite. The monitoring device designed in this paper has complete functions, and can realize high-amplitude and high-frequency overvoltage measurement. It has been applied in the project of 500kV Dinggong Smart Substation, which can provide support for fault analysis and insulation design, and is of great significance to ensure the safe and stable operation of power grid.