Nanocrystalline based Mitigation Technique for Very Fast Transient over Voltages in Gas Insulated Substations

R.Durga Rao, Et Al

doi:10.17762/turcomat.v12i2.1117

Abstract

: in gas insulated substations, issue of very fast transient over voltages is very familiar problem because of its effects on live ultra-high voltage equipment. During switching events of disconnectors and circuit breakers prestrikes and restrikes occur due to which voltage transients propagate through gas insulated switchgear. Reflection retraction of these transients increases voltage magnitude and generates very high frequency oscillations. Mitigation or suppression of these voltage transients is important to protect equipment and their dielectric strength and insulation. Due to very high frequency stress, they wield on the apparatus and their magnitude (up to 3.5pu), they create an important problem in the design of ultra-high voltage Gas Insulated Substations. In this paper nanocrystalline based mitigation technique for VFTOs is presented. Nanocrystalline rings can be placed around inner conductor of GIS switchgear. This method of mitigation technique is investigated with four ultra-high voltage substations simulation test setup. Simulation results are presented in MATLAB/SIMULINK

Highlights

Turkish Journal of Computer and Mathematics EducationR.Durga Raoa and Dr.M.Surya Kalavathib aAssistant Professor & Head, Department of EEE, JNTUHCEM
Less space necessity, high consistency, easy maintenance are the main reasons to prefer Gas insulated substations (GIS) over Air insulated substations (AIS) in recent years
Sulphur hexafluoride is the gas used as insulation medium in gas insulated switchgear as space required by it is very less compared to other insulation mediums including air

Summary

Turkish Journal of Computer and Mathematics Education

R.Durga Raoa and Dr.M.Surya Kalavathib aAssistant Professor & Head, Department of EEE, JNTUHCEM. BProfessor (on-lien), Department of EEE, JNTUH, Vice-Chancellor, Yogi Vemana University, Kadapa. Abstract: in gas insulated substations, issue of very fast transient over voltages is very familiar problem because of its effects on live ultra-high voltage equipment. During switching events of disconnectors and circuit breakers prestrikes and restrikes occur due to which voltage transients propagate through gas insulated switchgear. Reflection retraction of these transients increases voltage magnitude and generates very high frequency oscillations. Nanocrystalline rings can be placed around inner conductor of GIS switchgear This method of mitigation technique is investigated with four ultra-high voltage substations simulation test setup.

1.Introduction

With Nanocrystalline as mitigating device

With additional Nanocrystalline as mitigating device

Findings

Conclusion