EGAT comes up with innovation to deal with corona effects

         Corona is a phenomenon arising when high - power electron runs out of critical electric areas such as a sharp edge of a conductor or an insulator, causing the surrounding air molecules to ionise to create light - emitting sparks and “zzz” sound. The air molecules which are split will transform from being neutral to electrode, and a “trip” of the system can occur when the corona position is large enough to create short circuit to the ground.

         Corona also creates high - frequency signals which interfere the control system and electronic equipment. Corona is a phenomenon associated with all power dispatching systems, particularly in dusty areas and near sea with salt mist. Sometimes problems with corona can be severe to the extent of creating short circuit for the main transmission lines and undermining power supply security.

         These problems give rise to the innovation called the “Hot Line Robot”, a robotic cleaner of the Main Bus Support (MBS).


         Get to know Hot Line Robot?

         This is a brainchild of a 7 - man team at EGAT, namely Charoen Kamkong, Kritsawat Tonggam, Samart Yukong, Anon Yoksao, Jamlong Pawangsawat, Thamrong Ruengtong and Thanasit Jarunsak.

         Aside from winning a contest at EGAT, the innovation also received a gold award from the “46th International Exhibition of Inventions of Geneva” held in the Switzerland in April this year. It brought pride to EGAT and Thailand as a whole.


         What about cleaning the Main Bus Support?

         The first question that emerges is why we need to create a robot to clean the Main Bus Support (MBS).

         MBS is an important piece of equipment for power transmission, and if its surface is covered by dust, salt mist or other pollutants, its insulating property will be deteriorated, leading to a short circuit and a consequential blackout over a wider area - the effect of corona phenomenon.

         Normally, when the MBS gets dirty, it can be cleaned by a high pressure washer without the need for power cut. But EGAT has only one high pressure washer in hands, and such limitation means that it may not serve the purpose promptly, thus risking a short circuit situation. And sending up technicians to do the cleaning means a power cut is necessary, and that affects power users.

         Therefore, the robot was created to perform the cleaning of MBS without suspending electricity supply.


         Brainchild from a Car Washer

         The creation of Hot Line Robot was inspired by a car washer and operated by a motor with a remote control.

         The robot is capable of doing a 360 - degree task and can be installed by four persons. It can work on 115 kV and 230 kV MBTs on poles with 6 and 8 inches in width and 4-6 meters in height – the basic types of all the poles used at EGAT’s switchyards.

         This device is not only safe to use but represents a substantial cost saving for carrying out the same task as by a high pressure washer vehicle, which costs 7.5 million baht a unit, against 37,995 baht required to build a robot with locally - sourced materials.


         Building on the Innovation

         With proven merits of the robot, there has been great interest from agencies and industries which operate switchyards in industrial parks and coastal areas and prone to corona effect to see the innovation being developed on a commercial scale.

         EGAT has reckoned the need to produce more robots and make it even more user - friendly.