Research on magnetic bias characteristics of power grid transformer based on GIC

In order to study the exact effect of geomagnetic storms induced current (GIC) on transformer excitation characteristics, the Montreal observatory in Anhui Province in China was carried out in terms of magnetic wave data an soil resistivity parameters, consequently the area communication network frame model is established, followed by the calculation of earth magnetic field and geomagnetic storms induced current during (GIC) by using plane wave method. Further, based on UMEC transformer model, effect of GIC and geomagnetic field on transformer excitation characteristics in the interested areas are carried out by using CDEGS software to simulate the electric power system network and transformer nodes. eventually GIC calculations and risk assessments during geomagnetic storms are figured out. The results show that under the influence of strong solar storms, geomagnetic storms have a strong impact on the AC power grid in the interested area, GIC induced in the grid is much higher than that in the DC power transmission, results in an increased e peak value of the transformer excitation current. The proposed method can provide a reference for GIC calculation in the power system and its influence on the magnetic bias characteristics of the transformer.