Grounding System Analysis and Design Considerations for Large Hydroelectric Power Plant

Abstract:

Grounding system analysis and design considerations for large hydroelectric power plant are analyzed and discussed in this paper. The main work that has been carried out includes: constructing adequate soil structures and analyzing the effects of the finite heterogeneous soil structure, the modeled river length and the water reservoir levels; conducting accurate fault current distribution calculations and studying the influence of circulating current on the touch and step voltages. The paper discusses the design of the grounding system and its safety performance while considering the impact of the circulating current and inductive coupling from cables and long parallel conductors inside the plant. Two practical examples have been provided in this paper. Furthermore, the paper demonstrates the effectiveness of using heterogeneous finite soil volumes to analyze large hydroelectric power stations and confirms that accurate grounding software packages are required to account for large circulating currents within the ground conductors and strong inductive coupling that exists between metallic elements within the substation. The results and discussions presented here can be used as a reference for engineers to analyze extensive grounding systems and to design appropriate grounding systems for large hydroelectric power plant.

• Periodical: Advanced Materials Research (Volumes 516-517)
• Pages: 1359-1366
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.516-517.1359
• Online since: May 2012
• Authors: Ye Xu Li, Farid Paul Dawalibi, Jin Xi Ma
• Keywords: Fault Current, Finite Soil, Grounding, Hydroelectric Power Plant, Safety, Touch Voltage

References

[1] J. Ma and F.P. Dawalibi, "Analysis of Grounding Systems in Soil with Finite Volumes of Different Resistivities" IEEE/PES Trans. on PWRD, Vol. 17, No. 2, April 2002, pp.596-602.

DOI: 10.1109/61.997944

[2] N. Mitskevitch, J. Ma, and F. P. Dawalibi, "Study of Grounding System Safety Aspects in the Presence of Finite Heterogeneities", IEEE/IAS Workshop on Electrical Safety in Industry, New Delhi, April 14-15, 2000.

DOI: 10.1109/esw.2000.848332

[3] F. P. Dawalibi, N. Mitskevitch and G. Allard, "Grounding Analysis of Large Hydroelectric Generating Complex Using Soil Structure Containing Heterogeneous Volumes", The 17th Conference of the Electric Power Supply Industry (CEPSI), Macau, October 27 - 31, 2008.

[4] W. Ruan, R. Southey, and F. Dawalibi, D. Czarnomski, and G. Farra "Effect of Circulating Current from Local Generators in Grounding Study of a Large Power Plant," IEEE/IAS Workshop on Electrical Safety in Industry, New Delhi, April 14-15, 2000.

DOI: 10.1109/esw.2000.848331

[5] Y. Li and F. P. Dawalibi, "Practical and Realistic Considerations of Fault Current Analysis" The International Conference on Electrical Engineering (ICEE 2011), Hong Kong, July 10 - 14, 2011.

[6] R. D. Southey and F. P. Dawalibi, "Improving the reliability of power systems with more accurate grounding system resistance estimates," Proceedings of the IEEE-PES/CSEE International Conference on Power System Technology, PowerCon 2002, Kunming, China, October 13-17, 2002, Vol. 1, pp.98-105.

DOI: 10.1109/icpst.2002.1053512

[7] IEEE Std. 80-2000, IEEE Guide for Safety in AC Substation Grounding, IEEE, 2000.