The 110 kV shunt reactors

as important equipment in the UHV AC substations

are tasked with improving the reactive power distribution of lightly loaded lines

reducing the active power loss of the lines

and enhancing the efficiency of power transmission

making their safe and stable operation crucial. Currently

all in-service 110 kV shunt reactors adopt the dry-type air-core structure. However

the special environmental conditions of high altitude are easy to accelerate the aging of the insulation layer of the hollow reactor

and the thermal expansion coefficient of the wire and the insulation layer is different

leading to cracking

resulting in the discharge of the outer insulation. This article investigates and studies the manufacturing capabilities of manufacturers and special optimization measures in highaltitude environments. Combining relevant regulations and practical application needs

a technical and economic comparison is conducted on the application of 110 kV dry and oil immersed reactors in high-altitude areas. Suggestions for the selection of 110 kV shunt reactors in UHV AC substations in high altitude areas are proposed at present.