Multilayer PCB Sensor for Eddy Current Inspection of Accident Tolerant Fuel Rods
Year: 2026
Type: article
Abstract: Fuel rods in nuclear power plants operate for 3–6 years under extreme conditions—requiring regular in service inspections to prevent failures and ensure optimal performance. The thin chromium coating applied on the ATF fuel rods (typically 10 to 20 μm) as well as any oxidation occurring during operation are safety relevant and can be inspected by means of eddy currents. This letter evaluates several PCB-based sensor designs—including single-layer and multi-layer configurations—to identify the most robust solution for real-time monitoring. The eddy current instrument operates in a sweep mode with a frequency range of 0.5 to 100 MHz. When analysing the measurement signal for its suitability to determine chrome thicknesses a high-dimensional feature space involving not only the high number of frequencies but also the real, imaginary part, magnitude, and phase of the complex voltage is available. The study demonstrates that optimized probe design and signal processing achieve a measurement uncertainty of < ±0.7 μm on reference specimen with known coating thickness - sufficient for early degradation detection.
Source: IEEE Sensors Letters
Language: English
Subfield: Mechanical Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $2,645
OpenAlex ID: W7204139564