Uncertainty analysis of geomagnetically induced currents based on polynomial chaos technique

The knowledge of GIC level is important to prevent power system from the damage derived by GIC. Geoelectric field and GIC would be influenced by geomagnetic disturbance, earth conductivity, and power network structure. For these uncertain factors, polynomial chaos(PC) technique can be used to analyze their effects on GIC. Taking earth conductivity as random variable, the geoelectric fields of four type earth structures are compared. And then GICs of Xinjiang 750kV network are estimated. The distribution of £-field and GIC are achieved which provides useful reference for system operators.