Investigation of Neel Effect technology for current sensors in next-generation aeronautical applications

This paper deals with disruptive current-sensor technology for next-generation aeronautical applications. Sensors based on the Neel Effect principle are being developed using superparamagnetic nanostructured materials. The magnetic and mechanical proprieties of the raw material bring significant improvements in performance compared to conventional sensors. After reviewing the need to improve existing sensor technologies, the first section of this paper presents the state of the art of the sensing techniques currently used in aeronautical applications and outlines their main advantages and limitations. The second section focuses on Neel Effect sensor technology. The principle of this sensing technique and its theoretical benefits are described and compared to existing Hall effect and Rogowski coil technologies. The Neel Effect current sensor works like a magnetic DC transformer to measure a current carried on a conductor of flexible geometric shape. The transformer ratio depends only on the number of coil turns. This specific characteristic provides good linearity and low sensitivity to temperature variations. The sensor is able to measure DC or AC current in a broad range of bandwidths, currents and operating temperatures. The third section reviews progress in the development of Neel Effect current sensor technology. The objective is to qualify this technology for both existing and future aeronautical applications.