Structural optimization of magnetostrictive composite materials in magnetostrictive current sensor

Fiber optic current sensor based on magnetostrictive composite material is suitable for multiple industrial fields. Aiming at increasing the low sensitivity caused by conventional magnetostrictive composites, this work designed optimized magnet focusing structure of magnetostrictive composite material to develop high-performance fiber optic current sensor. The influence of magnetic focusing structures on the performance of current sensor was analyzed and validated through theoretical modeling and finite element-based simulation. Experimental tests were carried out to validate the superiority of proposed sensor compared with the existing sensors. Results show that the dimensional difference in the four proposed magnetostrictive composite structures (section B) leads to the different magnetic field distribution, and the proposed sensors are more sensitive than those of traditional structures. A repeatability error of 2.5%, a sensitivity of 0.16952 μϵ A⁻¹, and a linearity of 2.2% can be achieved by the proposed hourglass type sensor with low-cost and wide range between 0 A and 900 A.