Novel chirp tuning technique for fiber Bragg gratings without center wavelength shift using simply supported beam

2001 ◽  
Author(s):  
Yunqi Liu ◽  
Jianping Yao ◽  
Xinyong Dong ◽  
Jiangliang Yang
2007 ◽  
Vol 25 (11) ◽  
pp. 3580-3588 ◽  
Author(s):  
Paulo de Tarso Neves ◽  
Alexandre de Almeida Prado Pohl

Sensors ◽  
2020 ◽  
Vol 20 (7) ◽  
pp. 1834
Author(s):  
Jie Wei ◽  
Yanpeng Hao ◽  
Yuan Fu ◽  
Lin Yang ◽  
Jiulin Gan ◽  
...  

Icing detection of composite insulators is essential for the security and stability of power grids. As conventional methods have met difficulties in harsh weather, a 110 kV composite insulator with embedded Fiber Bragg Gratings (FBGs) was proposed for detecting glaze icing in this paper. FBG temperature compensation sensors in ceramic tubes were adopted for simultaneous measurement of icicle loads and temperature. Then, temperature calibration experiments and simulated icicle load experiments were carried out to obtain temperature and icicle load characteristics of FBGs. The results showed that temperature sensitivities of FBG strain sensors and FBG temperature compensation sensors were 18.16 pm/°C, and 13.18 pm/°C, respectively. Besides, wavelength shifts were linearly related to icicle loads within the polar angle range of −60° to 60°, and the load coefficient of FBG facing the icicle was -34.6 pm/N. In addition, the wavelength shift generated by several icicles was equal to the sum of wavelength shifts generated by each icicle within the polar angle range of −15° to 15°. Finally, icicles can cause wavelength shifts of FBGs within a big shed spacing. The paper provides a novel icing detection technology for composite insulators in transmission lines.


2001 ◽  
Author(s):  
Xiaopeng Dong ◽  
Beatrice C. Chu ◽  
Benshun Yi ◽  
K. S. Chiang

2004 ◽  
Vol 43 (5) ◽  
pp. 432-434 ◽  
Author(s):  
Zhiyong Zhao ◽  
Shuang Zhang ◽  
Yongsen Yu ◽  
Zhongchang Zhuo ◽  
Jian Zhang ◽  
...  

Sensors ◽  
2020 ◽  
Vol 20 (19) ◽  
pp. 5522
Author(s):  
Krzysztof Skorupski ◽  
Sławomir Cięszczyk ◽  
Patryk Panas ◽  
Piotr Kisała

This article presents the effect of fiber Bragg gratings side lobes on interrogation systems consisting of sensor and matched filters. The conducted research shows that high-value side lobe structures applied as sensors and/or filters are characterized by some interesting properties. The paper presents both numerical analysis and experimental verification of the fiber Bragg gratings (FBG) interrogation systems with matched filters for gratings containing high side lobes. Numerical modeling of Bragg structures was performed for two different cases: uniform and inverse apodization. Modification of apodization can change the side lobe reflectance level even above levels found in uniform structures. This is a case not described in the literature, especially in terms of possible applications. Transfer characteristics, i.e., the relationship between power intensity as a function of wavelength shift, were determined. A collection of gratings with spectra corresponding to those analyzed in numerical experiments were fabricated. Next, the transfer characteristics of the interrogation systems containing real FBG were determined. The properties of the proposed systems are described. It has been shown that a significant level of sidebands, which is often the subject of many drawbacks in filtering or telecommunications systems, can be an advantage. It has been demonstrated that a high level of side lobes can be used to increase the measurement range of the FBG sensor interrogation systems. It has been determined numerically and confirmed experimentally that from the point of view of the design of sensor interrogation systems, it is beneficial to combine specific pairs of gratings: one with a spectrum characterized by a low side lobe level and a second one in which the spectrum has very high side lobes.


Sign in / Sign up

Export Citation Format

Share Document