Research On Methodology For Power Grid GIC Event Prediction Based On Solar Wind Parameters

Significant progress has been made in researches on the geomagnetically induced currents (GICs) in China’s power grid so far. Mechanisms of the disastrous GICs caused by geomagnetic-storm encroachment in the power grid has been revealed, showing its liability of incurring severe damage upon China’s future power grid, which makes shielding the power grid from geomagnetic disaster an urgent issue. This dissertation proposed the methodology to forecast GIC events based on solar-wind parameters, targeting at the calculation and forecasting of GICs in the power grid with observed data of the solar-wind, so as to provide supports for the strategic decision-making in power grid operation and disaster prevention.The main work of the dissertation and innovations in the findings are as follows:Using full node model and nodal admittance matrix, GICs are calculated with power grid models respectively reflecting China’s Gansu grid (with 750kV and 330 kV voltage levels) and the newly-built ultra high voltage power grid (with 1 OOOkV and 500kV voltage levels). The interactions between GICs in the networks of the two voltage levels in each case have been analyzed whereby the characteristics of such interactions and the mechanism of the formation of such disastrous GICs in power grids are revealed. These findings can provide valid and exquisite data for further investigations on disaster prevention.To meet the requirement of making GIC forecast based solely on observed solar wind parameters, this research analyzed the correlation between parameters of coronal mass ejection (CME), interplanetary solar wind parameters and characteristic parameters of GICs such as GIC value and spectrum. The energy distribution of GICs in the power grid in different stages of a geomagietic storm were also studied. Findings of this part of the research revealed the contribution of the solar wind parameters to the GIC, whereby the dissertation put forward the framework to forecast GICs with solar wind parameters.According to the aforementioned findings, this dissertation proposed to make GIC forecast with 3D magnetohydrodynamic (MHD) model from space physics so as to preliminarily establish the causality between GIC events, CME and interplanetary solar wind events. It is also proposed here a GIC forecasting algorithm that uses interplanetary solar wind data as inputs, and the algorithm was validated by comparing its GIC output with monitored GIC data.Research of this dissertation revealed mechanisms of the GIC formation as a disastrous derivative of geomagnetic storms and also provided valid data for the corresponding development program of the state. The dissertation proposed a GIC forecasting method based on observed data of solar wind, which could serve as a boost to the strategic decision-making in power grid operation and disaster prevention.