Abstract: In eddy current thermography testing research, inductors predominantly employ high-frequency and high-current excitation methods to detect surface and subsurface defects in materials. The detection objects are mostly flat, and the static heating area of the inductors is relatively small. However, equipment such as pipelines and storage tanks in the petrochemical industry often feature curved surface structures and operate in environments with stringent explosion-proof requirements, which impose strict limitations on excitation current. Consequently, the detection efficiency and applicability of eddy current thermography technology are significantly limited in such scenarios. To address these issues, this study employs numerical simulation methods to design a large-sized curved magnetic core inductor suitable for weak-excitation conditions, aiming to resolve the dependency on high current and the compatibility between inductors and curved surface detections. A comparison with the heating performance of planar magnetic core inductors demonstrates that the curved magnetic core structure maintains heating capacity and uniformity on a small curvature radius while avoiding mechanical interference. Based on the designed structural parameters, optimal heating solutions for different curvature radius ranges are derived: a curved magnetic core inductor is suitable for curvature radii less than 1 m; a parallel arrangement of planar magnetic cores for radii between 1 m and 7 m; and a perpendicular arrangement of planar magnetic cores for radii greater than 7 m. Under weak-excitation conditions (15 A, 50 Hz), a relatively uniform heating is obtained on curved surfaces, which enhances detection safety. This study effectively provides technical support for the application and promotion of this technology in high-risk environments such as petrochemical facilities.