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Improvement of Thermal Stability of Optical Current Sensors Based on Polymeric Optical Integrated Circuits for Quadrature Phase Interferometry

사분파장 위상 간섭계 폴리머 광집적회로 기반 광전류센서의 온도 안정성 향상 연구

  • Chun, Kwon-Wook (Department of Electronics Engineering, Pusan National University) ;
  • Kim, Sung-Moon (Department of Electronics Engineering, Pusan National University) ;
  • Park, Tae-Hyun (Department of Electronics Engineering, Pusan National University) ;
  • Lee, Eun-Su (Department of Electronics Engineering, Pusan National University) ;
  • Oh, Min-Cheol (Department of Electronics Engineering, Pusan National University)
  • 천권욱 (부산대학교 전자전기컴퓨터공학과) ;
  • 김성문 (부산대학교 전자전기컴퓨터공학과) ;
  • 박태현 (부산대학교 전자전기컴퓨터공학과) ;
  • 이은수 (부산대학교 전자전기컴퓨터공학과) ;
  • 오민철 (부산대학교 전자전기컴퓨터공학과)
  • Received : 2019.11.09
  • Accepted : 2019.11.21
  • Published : 2019.12.25

Abstract

An optical current sensor device that measures electric current by the principle of the Faraday effect was designed and fabricated. The polarization-rotated reflection interferometer and the quadrature phase interferometer were introduced so as to improve the operational stability. Complex structures containing diverse optical components were integrated in a polymeric optical integrated circuit and manufactured in a small size. This structure allows sensing operation without extra bias feedback control, and reduces the phase change due to environmental temperature changes and vibration. However, the Verdet constant, which determines the Faraday effect, still exhibits an inherent temperature dependence. In this work, we tried to eliminate the residual temperature dependence of the optical current sensor based on polarization-rotated reflection interferometry. By varying the length of the fiber-optic wave plate, which is one of the optical components of the interferometer, we could compensate for the temperature dependence of the Verdet constant. The proposed optical current sensor exhibited measurement errors maintained within 0.2% over a temperature range, from 25℃ to 85℃.

광섬유가 지니는 패러데이 효과를 이용하여 전류의 세기를 측정하는 광전류 센서 소자를 설계 및 제작하였다. 센서 소자의 동작 안정성을 향상시키기 위하여 편광회전 반사 간섭계와 사분 파장 위상 간섭계 구조를 도입하였다. 이 복잡한 구조를 구성하는 다양한 광소자들은 하나의 폴리머 광집적회로로 구성하여 작은 크기로 제작되었다. 본 구조를 이용하면 외부에서 별도의 바이어스 피드백 제어가 필요 없는 상태에서 전류를 측정하는 센싱 동작을 수행할 수 있다. 또한 온도변화나 외부진동으로 인한 광센서 특성 변화를 제거하여 안정적인 특성을 유지하는 광전류센서를 구현할 수 있다. 그러나 패러데이 효과를 결정짓는 베르데상수는 온도에 따라 미소한 값의 변화를 가지고 있다. 본 연구에서는 이 변화로 인한 광전류센서의 온도의존성을 극복하기 위한 연구를 수행하였다. 편광회전 반사 간섭계의 부품인 광섬유 사분 파장판의 길이를 최적값으로부터 벗어나는 상태로 맞추어 줌으로써 베르데 상수의 온도의존성에 의해 나타나는 광전류센서의 스케일 팩터 변화를 보상해줄 수 있었다. 온도변화를 보상한 광전류센서는 주변 온도를 상온에서 85℃로 올리는 동안, 센서 측정 신호의 온도 의존성이 0.2% 이내로 유지되는 것을 확인했다.

Keywords

References

  1. K. Kurosawa, "Development of fiber-optic current sensing technique and its applications in electric power systems," Photon. Sens. 4, 12-20 (2014). https://doi.org/10.1007/s13320-013-0138-z
  2. K. Bohnert, P. Gabus, J. Nehring, H. Brandle, and M. G. Brunzel, "Fiber-optic current sensor for electrowinning of metals," J. Lightwave Technol. 25, 3602-3609 (2007). https://doi.org/10.1109/JLT.2007.906795
  3. J. D. P Hrabluik, "Optical current sensors eliminate CT saturation," in Proc. IEEE Power Engineering Society Winter Meeting. Conference Proceedings (New York, USA, Jan. 2002), pp. 1478-1481.
  4. Y. N. Ning, Z. P. Wang, A. W. Palmer, K. T. V. Grattan, and D. A. Jackson, "Recent progress in optical current sensing techniques," Rev. Sci. Instrum. 66, 3097-3111 (1995). https://doi.org/10.1063/1.1145537
  5. K. Bohnert, P. Gabus, J. Kostovic, and H. Brandle, "Optical fiber sensors for the electric power industry," Opt. Lasers Eng. 43, 511-526 (2005). https://doi.org/10.1016/j.optlaseng.2004.02.008
  6. R. M. Silva, H. Martins, I. Nascimento, J. M. Baptista, A. L. Ribeiro, J. L. Santos, P. Jorge, and O. Frazao , "Optical current sensors for high power systems: a review," Appl. Sci. 2, 602-628 (2012). https://doi.org/10.3390/app2030602
  7. K. Bohnert, P. Gabus, J. Nehring, and H. Brandle, "Temperature and vibration insensitive fiber-optic current sensor," J. Lightwave Technol. 20, 267-276 (2002). https://doi.org/10.1109/50.983241
  8. A. Enokihara, M. Izutsum, and T. Sueta, "Optical fiber sensors using the method of polarization-rotated reflection," J. Lightwave Technol. 5, 1584-1590 (1987). https://doi.org/10.1109/JLT.1987.1075449
  9. G. Frosio and R. Dandliker, "Reciprocal reflection interferometer for a fiber-optic Faraday current sensor," Appl. Opt. 33, 6111-6122 (1994). https://doi.org/10.1364/AO.33.006111
  10. M.-C. Oh, J.-K. Seo, K.-J. Kim, H. Kim, J.-W. Kim, and W.-S. Chu, "Optical current sensors consisting of polymeric waveguide components," J. Lightwave Technol. 28, 1851-1857 (2010). https://doi.org/10.1109/JLT.2010.2049093
  11. M.-C. Oh, W.-S. Chu, K.-J. Kim, and J.-W. Kim, "Polymer waveguide integrated-optic current transducers," Opt. Express 19, 9392-9400 (2011). https://doi.org/10.1364/OE.19.009392
  12. G. M. Muler, L. Yang, A. Frank, and K. Bohnert, "Simple fiber-optic current sensor with integrated-optics polarization splitter for interrogation," in Proc. Imaging and Applied Optics (Seattle, USA, July. 2014), paper AM4A.3.
  13. D. Stowe and T. Y. Hsu, "Demodulation of interferometric sensors using a fiber-optic passive quadrature demodulator," J. Lightwave Technol. 1, 519-523 (1983). https://doi.org/10.1109/JLT.1983.1072135
  14. H.-J. Park and M. Song, "Fiber grating sensor interrogation using a double-pass Mach-Zehnder interferometer," IEEE Photon. Technol. Lett. 20, 1833-1835 (2008). https://doi.org/10.1109/LPT.2008.2004562
  15. K. B. Svensson, "Fiber optic current sensors," M. S. Thesis, Chalmers University of Technology Gothenburg, Sweden (2014).
  16. S.-M. Kim, T.-H. Park, G. Huang, and M.-C. Oh "Bias-free optical current sensors based on quadrature interferometric integrated optics," Opt. Express 26, 31599-31606 (2018). https://doi.org/10.1364/OE.26.031599
  17. W.-S. Chu, S.-M. Kim, and M.-C. Oh, "Integrated optic current transducers incorporating photonic crystal fiber for reduced temperature dependence," Opt. Express 23, 22816-22825 (2015). https://doi.org/10.1364/OE.23.022816