The use of long-period gratings to detect Sulphur Hexafluoride.
The combination of the increase in cost of Sulphur Hexafluoride (“SF6”), the registration of SF6 as a greenhouse gas and the use of SF6 at pressures above atmospheric has caused the need for SF6 detection equipment to arise. This research report outlines and reviews past and present technologies utilised, together with presently available commercial systems. Along with the review of available technologies, a proposed system utilising opto-electronic sensors to provide real-time detection is discussed. The proposed method investigated is the utilisation of Long-period gratings to detect slight refractive index changes of the ambient environment outside gas insulated systems and attempt to resolve the change in refractive index into detection mechanism for SF6. The method is shown to be possible, however currently not practically feasible. It is recommended that a practical investigation be undertaken to determine the real practical constraints theorised within but the magnitudes not yet established.