一种新型全绝缘光纤温度–磁场双参数传感器

A Novel All-dielectric Optical Fiber Temperature-magnetic Field Dual-parameter Sensor

温度与磁场传感技术已广泛应用于电力工业领域,但随着高电场、大范围温度波动以及空间约束等特殊感知场景的出现,如变压器内部温度、磁场的感知,对传感器的研发提出了新要求。该文设计一种新型全绝缘光纤温度–磁场双参数传感器,将光纤光栅与磁光晶体进行集成小型化封装与共光路结构设计,运用光纤光栅的热光效应、磁光晶体的法拉第效应分别感知温度、磁场变化,并设计出实时温度补偿方法以解决磁场测量中温度干扰问题。经测试表明,该传感器具有高空间分辨率与高绝缘可靠性,在15~85℃宽温度区间仍保持着系数为0.998的线性温度响应,可准确测量0.04~50 mT范围内磁场,并在0~10 kHz内表现出出色的动态响应性能,同时所提温度补偿方法将磁场测量相对误差限制至1.78%以下,进而可用于满足电力设备中一些特殊场景下温度–磁场的传感需求。

Temperature and magnetic field perceptions have been commonly employed in the power system.With new special application scenarios appearing(e.g.in power transformers),including strong electric field,wide temperature swing and insufficient installing space,the sensors are expected to be further improved.In this paper,a novel all-dielectric optical fiber temperature-magnetic field dual-parameter sensor is designed.Specifically,an optical fiber grating and a magneto-optical crystal are integrated in one package and placed into a single light path to reduce the sensor size.The thermal-optical effect of the grating and the Faraday effect of the crystal are applied to support the temperature and magnetic field perception respectively.Additionally,the real-time temperature compensation method for magnetic field measurement is proposed to improve the accuracy.Eventually,performance test results demonstrate that the sensor with high spatial resolution and insulation reliability can instantly respond to temperature variation with 0.998 degree of linearity in the wide range from 15℃to 85℃.Moreover,magnetic field in the amplitude range of 0.04~50mT and frequency range of 0~10kHz can be measured with high accuracy.The measurement error is limited below 1.78%by the proposed compensation method.Therefore,the designed sensor can further meet the temperature and magnetic field perception demand in the special application scenarios.