Optimal Grounding Planning of Overhead Transmission Lines Considering the Ground Potential Rise of Cable Connection Station

• Main Authors: Yun-Jhen-Ke, 柯芸蓁
• Other Authors: 周至如
• Format: Others
• Online Access: http://ndltd.ncl.edu.tw/handle/kj8v6e

碩士 === 國立臺北科技大學 === 電機工程研究所 === 104 === It is more and more popular that transmission system is composed of overhead lines and underground cables, which needs the cable connection station (CCS) for overhead lines and underground cables connections. The system frameworks and line parameters are discontinue at CCS, which let the electrical faults to happen easily and the faults associated with ground fault is the most common, and ground potential rise (GPR) has an adverse effect on system, equipment and personnel security. It is useful to increase overhead grounding wires and lower the tower grounding resistance are the most feasible measure for improve GPR, However, the effects of these measure on the GPR are still need to study for approaching to the optimal planning and design. This thesis will aim to study the effects of overhead grounding wires and grounding resistance are analyzed and the influence and the benefit are evaluated on the ground fault GPR of CCS. Firstly system modeling and analysis are based on the alternative program (ATP), considering lower the grounding resistance and whether to increase overhead grounding wires, and the tendency of CCS GPR are simulated by ATP. Based the simulation results, the cost and benefits of improvement are evaluated. Finally the planning of tower ground resistances and overhead ground wire arrangement with minimum cost will be searched for different GPR levels, and the comparisons between existent grounding planning are the proposed planning and provide the reference for constructing transmission system grounding.