Making VSC-HVDC control robust to geomagnetically induced current

Solar storms can affect the terrestrial power grid by inducing potential differences between points on the earth. These can couple into the power system through earthed structures such as transformer earths, which in turn can result in transformer saturation through geomagnetically induced current (GIC). For systems such as voltage-source converter (VSC) HVDC, this causes a variety of problems. This paper discusses the phenomenon, system modelling to assess the resulting problems and presents a compensate strategy to ameliorate GIC effects for VSC-HVDC.