Superconducting (SC) magnets for accelerator concepts are often synthesized by numerically optimizing magnetic field waveforms, a process that requires a subsequent solution of a constrained inverse problem to identify suitable SC magnet windings. When the desired field distribution is intuitive, the inverse process is facilitated by seeding preconceived coil distributions into design optimization methods for refinement. With more complex magnetic field distributions, an initial design may be unknown, and topology optimization tools are required to synthesize current distributions without a priori guidance from a subject matter expert. In this work, we develop a constrained inverse Biot-Savart topology optimization methodology that synthesizes optimal distributions of current density in racetrack-like SC coils. The problem structure is exploited through a computationally efficient quadratic programming formulation, and the method is applied to recently published magnetic field waveforms for a recirculating proton phase shifter, a proton therapy gantry, and dipole magnets with sharp field transitions. The method and results herein identify novel winding configurations that can help magnet designers bring accelerator concepts to fruition.

中文翻译：

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超导加速器磁体的逆 Biot-avart 优化


用于加速器概念的超导 (SC) 磁体通常通过数值优化磁场波形来合成，该过程需要随后求解约束反问题，以确定合适的 SC 磁体绕组。当所需的场分布是直观的时，通过将预先设想的线圈分布植入到设计优化方法中进行细化，可以促进逆过程。对于更复杂的磁场分布，初始设计可能是未知的，并且需要拓扑优化工具来合成电流分布，而无需主题专家的先验指导。在这项工作中，我们开发了一种约束逆 Biot-Savart 拓扑优化方法，该方法综合了类似跑道的 SC 线圈中电流密度的最佳分布。该问题结构是通过计算效率高的二次规划公式来开发的，并且该方法应用于最近发布的循环质子移相器、质子治疗台架和具有尖锐场转变的偶极磁体的磁场波形。本文的方法和结果确定了新颖的绕组配置，可以帮助磁体设计者将加速器概念变为现实。