Streamlined Stellarator Design: Single-Stage Optimization with Fixed Boundary Equilibria*

The quest for practical and economically viable fusion devices demands innovative approaches to overcome design challenges. With their complex coil systems and steady-state operation capabilities, stellarators have emerged as promising magnetic confinement devices. However, the traditional two-stage design process optimizes magnetic fields and coils separately, which usually leads to a time-consuming design process and can result in suboptimal coil configurations. In this work [1], we devised a novel single-stage optimization method using fixed boundary equilibria, allowing for simultaneous optimization of physics goals and engineering constraints. This approach creates a streamlined combined plasma-coil optimization process in stellarator design by incorporating both the plasma boundary and coil shapes as degrees of freedom in the optimization.  Our innovative method is adaptable to various vacuum and finite plasma pressure stellarator equilibria, offering improved efficiency and reduced computational time compared to conventional techniques. We will explore the methodology, applications, and implications for the future of fusion devices in plasma physics, showing applications of this method to quasi-symmetric, quasi-isodynamic, and particular designs using a minimal set of coils. Such findings usher in a new era of streamlined stellarator design, paving the way for more efficient and effective magnetic confinement fusion devices.

[1] R Jorge et al 2023 Plasma Phys. Control. Fusion 65 074003