DC Biasing Treatment Scheme for Zha-Qing ±800kV Project Zhalute Power Grid

Abstract

The rated operating current of ±800kV UHVDC transmission (UHVDC) is large, and the influence of grounding pole ground current on the transmission and reception network and its treatment is a subject to be studied. Combining with the construction of Zha-Qing (±800kV) project and using the historical magnetotelluric data, the three-dimensional resistivity model and the magnetic bias current model of Zhalute power grid are established. The calculation of magnetic bias current of Zhalute power grid is completed and the control scheme of DC magnetic bias is proposed. The theoretical analysis of governance effects and the test results after the implementation of the governance project show that the proposed model and algorithm are accurate and the proposed governance scheme is correct and effective; Finally, according to the problems found in the calculation of DC bias current and the treatment plan of Zhalute Power Grid in Zhaqing, the suggestions for grounding site selection and treatment methods are proposed.