Electro-Magnetic field Study in UHV Substations

Rapid increase in expansion of Electrical energy utilisation and ascending demand has led to increase in the transmission capacity, thereby necessity to upgrade the system to EHV & UHV levels. While operating switchyards/Transmission at Extra High voltage levels are being adopted by most utilities across globe, there is considerable impact on ecological system because of higher ionisation & radiation due to the higher voltage levels putting living beings’ survival at stake.

It is more evident that there is an essential need to mitigate the effects of electromagnetic field interference in the switchyards for human, livestock & plants. Enough studies are made and validated results are available for voltage levels up to 500 kV indicating value of fields within tolerable limits, research for 765 kV is underway. Hence, it has become mandatory that, the geometry of switchyard has to be decided considering the Electro-magnetic field and to restrict the values within limits. This technical paper deals on the electric and magnetic field effects for 765 kV switchyard and interpretation of EM field in analytical and real time measurement. A case study was conducted at a 765 kV Switchyard to examine the values of EM field using COMSOL software, where using finite element analysis, exact field values at specified height can be calculated and the results are compared with real-time measurement.