What is the potential value of composite shielded insulated tubular busbar bodies in the field of cryogenic superconductivity?
Publish Time: 2025-12-09
With the continuous upgrading of energy efficiency and power transmission technology, cryogenic superconductivity, due to its near-zero resistance, high current density, and strong magnetic field carrying capacity, is gradually moving from the laboratory to engineering applications, such as nuclear magnetic resonance imaging (MRI), particle accelerators, controlled nuclear fusion devices, and future superconducting grids. However, the stable operation of superconducting systems depends not only on the superconducting materials themselves but also on efficient, reliable, and low-loss current leads and busbar structures. Composite shielded insulated tubular busbar bodies, with their unique structural advantages and electrical properties, demonstrate significant potential value in cryogenic superconducting systems.1. Structural Advantages Meet the Requirements of Cryogenic EnvironmentsComposite shielded insulated tubular busbar bodies typically consist of a high-conductivity metal as the conductor core, covered with multiple layers of composite insulating material, and integrated with a metal shielding layer to suppress electromagnetic interference. Their tubular hollow structure not only reduces overall weight but also facilitates the introduction of cooling media internally, enabling thermal coupling with superconducting magnets or cables. This integrated design effectively solves the cracking risk of traditional solid busbars caused by thermal stress concentration at extremely low temperatures, while improving heat conduction efficiency and providing a stable cryogenic current path for the superconducting system.2. Excellent Electrical Insulation and Electromagnetic Shielding PerformanceIn superconducting devices, high current and strong magnetic fields coexist, placing stringent requirements on the insulation strength and electromagnetic interference resistance of the busbar. The composite shielded insulated tubular busbar body employs a high dielectric strength, low dielectric loss insulation system, maintaining stable insulation performance within the 4K–77K temperature range, preventing partial discharge or breakdown. Its outer metal shield effectively suppresses external electromagnetic noise interference to the superconducting coils, while reducing eddy current losses generated by the busbar's own alternating current. This is crucial for maintaining the stability of the superconducting state, especially in pulsed operation or high-field magnet systems.3. Reduced AC Losses and Improved System Energy EfficiencyAlthough the DC resistance of the cryogenic superconductor itself is zero, the current leads connecting it to the room-temperature power supply still exhibit Joule heat loss. Composite shielded insulated tubular busbars, through optimized conductor cross-sectional distribution and shielding design, can significantly reduce skin effect and proximity effect losses under AC operating conditions. Furthermore, their excellent thermo-electric synergistic design helps minimize heat leakage, reducing the additional load on the cooling system and thus improving the overall energy efficiency and operational economy of the superconducting device.4. Support for High Integration and Modular AssemblyModern large-scale superconducting equipment is extremely sensitive to wiring space. Composite shielded insulated tubular busbar bodies possess high mechanical strength, a small bending radius, and flexible 3D forming capabilities, allowing for installation along complex paths and saving valuable space. Their standardized interfaces and modular design also facilitate rapid on-site installation and maintenance, reducing construction difficulty and failure rates, making them particularly suitable for multi-channel, high-density current feedthrough scenarios.While composite shielded insulated tubular busbar bodies are not the superconducting material itself, they serve as a crucial bridge connecting the ambient temperature world and the superconducting world. Their comprehensive advantages in low-temperature stability, insulation reliability, electromagnetic compatibility, and system integration make them highly promising for application in the field of low-temperature superconductivity.
