Dynamic Simulation of Transformer Harmonic Effect under GIC
In the test,the primary winding currents were measured when subjected to diffferent DC invasions in the five loading states,including three-phase group (single-phase) transformer no-load,single-phase load with different power,three-phase four-wire symmetric load,and three-phase three-wire symmetric load.Analysis has been conducted on the primary winding current distortion caused by DC invasion in the aforementioned five loading states,particularly its correlation with harmonic distribution,various harmonics and DC,as well as the influence of geomagnetically induced current (GIC) harmonic effect under different operation modes.