Enhanced Grid Stability through GIC elimination and Grid Support

Geomagnetic Disturbances (GMDs) lead to the flow of Geomagnetically Induced Currents (GICs) in power systems. The GICs compromise the reliability of a power network by causing mis-operation or even damage to certain power equipment. The wye-grounded three-phase power transformers in transmission network provide the most appropriate path for the flow of GICs. This paper proposes a novel GIC mitigation approach that utilizes a power electronic circuitry integrated between the neutral point and earth ground of power transformers. In addition to automatic GIC mitigation, the device provides voltage regulation, voltage unbalance removal and harmonic isolation as added features. The proposed approach converts the traditional transformers into smarter one, thus, providing a step forward towards realization of the much-needed smart grids. The simulation results in Typhoon Hardware-in-the Loop (HIL) real-time simulator verify the efficacy of the proposed approach on a 765kV/345kV power transformer.