Optimal Design and Multicoils Quench Analysis of the EMPS Superconducting Magnet Employing Hybrid Genetic Algorithm

A 5-T low-temperature superconducting magnet was designed and will be fabricated for electro-magnetic property measurement system (EMPS) whose sample space is 50 mm in diameter. Since the sample space is twice larger than that of the conventional property measurement systems, it will be possible to measure the electro-magnetic properties of several samples at a time, therefore, measurement time could be reduced. With the genetic algorithm incorporated with the linear-programming, key design of the 5-T LTS EMPS magnet is introduced and followed by the detailed magnet specifications including field uniformity at 50-mm space, magnetic hoop stress, critical current margin, and dimensions. The linear-programming restricts the magnet space and structure to minimize the total volume of the wires. Meanwhile, the genetic algorithm calculates the layers, turns, and detailed dimensions of the magnet in the magnet space confined by the linear-programming. Furthermore, quench analysis on multicoils employing finite difference equations in liquid helium was carried out to verify the thermal stability of the LTS magnet. The quench simulation code calculates temperature profiles of the magnet considering heat transfer among the unit cells and joule heat of the magnet in three-dimensional space. The LTS magnet for 5-T EMPS will be fabricated according to the design results.