Speaker
Description
Magnetic diagnostics are essential for the measurement and control of plasma behavior in magnetic confinement fusion devices. However, conventional wound-coil magnetic probes face increasing challenges in future fusion reactors, including material degradation under strong nuclear radiation and high-energy neutron irradiation, as well as limited installation space caused by their relatively large probe volume. Low Temperature Co-fired Ceramic (LTCC) technology provides a promising route for developing compact, robust, and radiation-tolerant magnetic sensors for in-vessel applications.
This presentation reports the design, engineering implementation, and preliminary application of LTCC magnetic sensors for EAST in-vessel magnetic diagnostics. Compared with traditional wound probes, the developed LTCC sensors achieve a more than fivefold reduction in volume, while maintaining good diagnostic performance. The sensors exhibit a resonant frequency of approximately 195 kHz, enabling the detection of a wider range of magnetic perturbations. The equivalent effective sensing area reaches 0.25 m², providing a balance between signal sensitivity and spatial resolution. In addition, the LTCC-based structure shows improved signal-to-noise performance, which is beneficial for weak magnetic fluctuation measurements.
The LTCC probe system has been successfully installed inside the EAST vacuum vessel, forming a densely arranged poloidal array consisting of 35 groups with two measurement components in each group. The engineering experience obtained on EAST, including ceramic-vacuum compatibility, thermal cycling stability, installation reliability, and long-term operation in a tokamak environment, provides valuable experimental and engineering reference for similar magnetic diagnostic systems planned for ITER and future fusion devices.