No-Insulation Coil Under Time-Varying Condition: Magnetic Coupling With External Coil

Area of Science:

• High-temperature superconductivity
• Electromagnetism
• Electrical engineering

Background:

• No-insulation (NI) coils are increasingly used in superconducting magnets.
• Understanding their time-varying behavior, especially when magnetically coupled, is critical for performance and stability.
• Existing models may not fully capture the complex electromagnetic dynamics of NI coils under varying conditions.

Purpose of the Study:

• To experimentally and analytically investigate the time-varying electromagnetic behavior of a no-insulation (NI) high-temperature superconductor pancake coil.
• To evaluate the coil's performance both independently and when magnetically coupled to an external coil.
• To develop and validate a simulation model for characterizing this behavior.

Main Methods:

• Fabrication of an NI coil and an identical insulated coil for comparison.
• Utilizing a 300-mm/5-T low-temperature superconductor magnet as an additional external coil.
• Development of an equivalent circuit model to simulate the time-varying conditions of the NI and external coils.
• Comparison of experimental results with simulation data.

Main Results:

• Experimental data and simulation results showed good agreement.
• The proposed equivalent circuit model accurately represents the electromagnetic behavior of the NI coil.
• The model's validity was confirmed for both standalone and magnetically coupled configurations.

Conclusions:

• The developed equivalent circuit model is effective for characterizing the time-varying electromagnetic behavior of NI high-temperature superconductor coils.
• This validated model is a valuable tool for designing and analyzing superconducting magnets incorporating NI coils.
• The findings support the use of NI coils in applications requiring precise control over dynamic electromagnetic responses.