Research On Reform Measures Of Grounding Networ Of Jinjiang Hydropower

Hydropower station is economic, environmental, and substantial. Due to the large number of rivers in China as well as the growing demand of electricity, the number of hydropower stations is constantly increasing, especially the construction of Three Gorges and other large hydropower stations. Safe operation is the basic requirement of power station. The grounding resistance value is an important coefficient to ensure the safe operation of hydropower station. After the completion of constructing many hydropower station, the station's grounding resistance value is found higher than the value needed by the safe operation of hydropower station However, large-scale hydropower stations (including conventional hydropower station and pumped storage power station) are generally built on high mountains where the soil resistivity is high, therefore, in order to ensure the safe operation of power stations, and improve power supply reliability, special research and appropriate solutions must be done, and a suitable security system must be equipped.Grounding system in hydropower station is an important measure to ensure safe and reliable operation, security of personnel, electrical equipment. When short-circuit fault happens or other high current comes into the ground, if the grounding resistance is quite high, it will cause a potential rise in net; and if the grounding system design is unreasonable, the local potential difference of grounding system itself can be higher than the safe level. It can be seen that power system grounding problem is a seemingly simple, but in fact particularly complex and vital issue. It is directly related to personal safety, security and stability of power system operation. It can also effectively inhibit the generation of voltage rising or step voltage .This article first analyzes the influential factors of grounding resistance in hydropower station in detail, such as terrain features, structural features and environmental features of hydropower station. According to the results of field investigation and testing in Guangzhao hydropower Station and Jinjiang hydropower Station, the design of modification scheme in these two hydropower stations are completed .Grounding in hydropower station is analyzed. Issues of Grounding connection, voltage, excessive frequency resistance, corrosion of grounding are discussed. Specific, practical improvement measures are proposed in terms of problems existing in hydropower station to ensure the safe operation of hydropower stations, and play the referential role in comprehensive transformation of other stations .