High Performance Electrical Insulation For High Field Superconducting Accelerator Magnets

The U.S. Department of Energy (DOE) is participating in a series of high-energy physics projects that require the use of high-field superconducting magnets that operate in high radiation environments. For high-energy physics accelerators, the superconducting magnets represent the largest (in size, volume, mass, and cost) subsystem of the machine. Technologies that can advance the performance of these machines, reduce the size, improve the reliability, reduce the manufacturing risk, and reduce the cost of these devices are of critical need. Electrical insulation is one of the smaller subsystems in a magnet, yet is critical to the successful operation, reliability, and longevity of magnets. Electrical insulation with improved radiation performance, mechanical strength, thermal properties (including thermal conductivity), and high dielectric strength will allow a minimal thickness of insulation to be applied and thus increase the effective current density within the coil. Insulation performance goals for future accelerator magnets include radiation resistance at doses up to 200 MGy, compressive strengths up to 200 MPa, and improved heat transfer from the conductor and through the insulation. This paper will discuss approaches proposed by Composite Technology Development, Inc. to achieve these insulation goals.