Planar Coil Array Sensing and Control Methods

Thea Energy, Inc. 's planar coil stellarator concept simplifies the construction of superconducting magnets and the stellarator overall by shifting complexity historically in hardware to the control system. The Company's architecture utilizes a combination of planar encircling coils to generate the background toroidal magnetic field and shaping coils arranged in arrays to define the targeted plasma boundary. Prior generations of stellarators demonstrated that magnetic diagnostic placement can be optimized to accurately resolve plasma profile variations. This work extends the optimization framework to the placement of magnetic sensors for resolving shaping coil currents and positions. We present an experimental validation of the proposed approach, demonstrating that the optimized diagnostic layout enables accurate pose estimation of a superconducting magnet. We also propose a novel control technique for managing the current profile across an array of superconducting shaping coils. This control strategy is designed to support dynamic plasma boundary control during stellarator startup and transitions between operating points. The results underscore the importance of integrated diagnostic and control system design in realizing the potential of Thea Energy's planar coil stellarator architecture.