Electrical Characteristics of Smart Insulation 2G HTS Coils Based on Three Fabrication Methods

This paper describes a technique for building smart insulation (SI) 2G high temperature superconductor (HTS) coils and investigates their electrical characteristics. The SI method utilizes the metal-insulated transition properties of V
₂
O
₃
. The V
₂
O
₃
material acts as an insulator when the temperature is lower than a certain value. Above this temperature, the V
₂
O
₃
material becomes a conductor. This transition can be used as a temperature switch between the turns of the 2G HTS magnets. The SI method is used to satisfy both the stability and charging/discharging time constant requirements of 2G HTS coils. We explain in detail how to make V
₂
O
₃
paste using V
₂
O
₃
powder and three different methods for installing V
₂
O
₃
paste between the turns of the 2G HTS coil, which results in three different types of SI 2G HTS coils. These three types of SI 2G HTS coils are also discussed in terms of practical use.