基于马赫-曾德干涉仪的光纤电流互感器研究

Study on fiber-optic current sensor based on Mach-Zehnder interferometer

为进一步促进光学电流互感器(OCT)在电力系统中应用,将光纤传感技术与磁致伸缩材料相结合,提出了一种新型的OCT的设计方法。将干涉仪的两个臂分别沿平行于磁场方向和垂置与磁场方向回环粘贴在正方形磁致伸缩材料的两个表面上,确保光纤均匀、对称分布,上下表面上光纤正交排列、匝数相同,形成双臂对称型的马赫-曾德干涉仪,得到了一定的温度补偿,消除了磁致伸缩材料热膨胀带来的测量影响,测量误差为0.65%,表明了该结构能达到温度补偿的效果,在一定程度上解决了阻碍OCT实用化进程的测量温漂问题。

Aiming at one severe problem optic current transducer （OCT） faced, temperature excursion that baffles its utility in power system, this paper presents a new method of designing OCT through combining optical fiber sensing and magnetostrictive materials. Pasting the two arms of interferometer on the two surfaces of square magnetostrictive material respectively and ensuring that the optical fiber is pasted uniformly, and the same turns optical fiber is pasted on the two surfaces, which constitutes a symmetrical type of arms M-Z interferometer. This makes fiber-optic current sensor based on the magnetostrictive material have temperature compensation. It can weaken the effects of thermal expansion of the magnetostrictive material. In the experiment, the measurement error of sensing head is 0.65%. It shows that the structure can achieve the effect of temperature compensation to some extent, so that it can meet the demands of the development of modern power system.