Optimizing the Design of 400 kV HVAC and 500 kV HVDC Double Circuit Hybrid Transmission Lines: Analysing Electric and Magnetic Field Impact

Abstract

India’s transmission network has been growing steadily in the past few years to support the transition to renewable energy. The country added 14,895 circuit km of line length in FY22 and 78,982 MVA of transformer capacity, an increase of 3.4 per cent and 7.7 per cent respectively over the previous year. With more ambitious climate change targets of 500 GW of non-fossil fuel capacity by 2030 set for the future, significant investments are underway to upgrade the country’s grid infrastructure at the interstate as well as the intra-state transmission levels. The National Infrastructure Pipeline estimates a cumulative investment of Rs 3,040.50 billion in the transmission segment till FY2025. Recent policy efforts have been directed to expedite project development and improve transmission system planning. The newly launched PM Gati Shakti initiative is expected to streamline project development and reduce time and cost overruns for all infrastructure projects including transmission, which will help address RoW issues. With rapidly changing markets, ramping up investments in new technologies to make the grid more reliable, secure and smart is also becoming an imperative for transmission domain. Newly introduced Hybrid Transmission Line concept in India which justify the feasibility for implementing AC and DC conductors on same tower or sharing same Right of Way can improve grid reliability, efficiency and cost benefits for tower infrastructure will take advantage of new capabilities to support grid operations. The objective of this research paper is to discuss the recent trends and developments, and highlight the future plans and upcoming opportunities in the Indian power transmission sector. The paper will also highlight the proposed optimised design for implementing Hybrid Transmission Line by considering Electric Field and Magnetic Field as an objective function which affect the Environmental conditions. This paper also showcases one case study of Hybrid Transmission Line Model and verified their EMF result analysis comparison with the ICNIRP and CBIP guidelines. Results shows that the proposed hybrid transmission line model is feasible for Indian Geological condition and provides solutions to the utility engineers. The main objectives of this paper are to create efficient, reliable and modern grids, and better manage their transmission assets with an exemplified framework for designing hybrid lines for the possible improvements in servitude utilisation and power density by using hybrid HVDC/EHVAC transmission lines.