GAS INSULATED SYSTEMS (SYLLABUS MTECH-EPS ELECTIVE II SEM)

UNIT–I: INTRODUCTION TO GIS AND PROPERTIES OF SF6
Characteristics of GIS- Introduction to SF6 - Physical properties-Chemical properties - Electrical
properties-Specification of SF6 gas for GIS application - Handling of SF6 gas before use - Safe
handling of Sf6 gas in electrical equipment - Equipment for handling the SF6 Gas - SF6 and
environment.
UNIT–II: LAYOUT OF GIS STATIONS
Advancement of GIS station - Comparison with Air Insulated Substation - Economics of GIS -
User Requirements for GIS - Main Features for GIS - Planning and Installation components of a
GIS station.

UNIT–III: DESIGN AND CONSTRUCTION OF GIS STATION
Introduction - Rating of GIS components - Design Features - Estimation of different types of
Electrical Stresses -Design Aspects of GIS components - Insulation Design for Components -
Insulation Design for GIS - Thermal Considerations in the Design of GIS - Effect of very Fast
Transient Over-voltages (VFTO) on the GIS design - Insulation Coordination systems - Gas
handling and Monitoring System Design.
UNIT-IV: FAST TRANSIENT PHENOMENA IN GIS
Introduction- Disconnector Switching in Relation to Very fast Transients-Origin of VFTOPropagation
and Mechanism of VFTO-VFTO Characteristics- Effects of VFTO-Testing of GIS for
VFTO.
UNIT–V: SPECIAL PROBLEMS IN GIS AND GIS DIAGNOSTICS
Introduction - particles their effects and their control- Insulating Spacers and their Reliability - SF6
Gas Decomposition - Characteristics of imperfections in insulation - Insulation Diagnostic
methods - PD Measurement and UHF Method.
TEXT BOOK:
1. M. S. Naidu,” Gas Insulated Substations”- IK International Publishing House.