| The accidents caused by icing, such as line disconnection, tower failure and insulator surface flashover, occurred in many countries. With ice condition monitoring of power lines, the state of ice accumulation on the conductor may be detected in early stage so that appropriate counter measures can be initiated in time. The conventional ice monitoring system on overhead transmission lines chiefly composed of electric element, and there are many disadvantages of these monitoring systems, such as:sensitive to EMI (Electro-Magnetic Interference), short lifespan, require on-site power. To overcome there disadvantages, Fiber Bragg Grating is adopt to develop sensors used in ice monitoring.In this Dissertation, the affection of the adhesive to the stain measurement is investigated based on the Maxwell model of viscoelastic, and the requirement of the adhesive to achieve excellent strain measurement is obtained:The adhesive should have a low viscosity before cured, which can obtain a better strain transfer coefficient, and a high viscosity after cured, which can increase the long-time reliability.A novel canister FBG load cell is proposed to solve the problem of electrical load cell. In order to improve the measuring accuracy of the tension sensing section under eccentric load, the elastic element in the tension sensing section is designed as a closed-loop U structure, with two FBG symmetrically glued on the element. Finite Element Method (FEM) is introduced to investigate the strain distribution on the conventional structure and the improved structure under eccentric load, and the results show that the heterogeneous degree of the conventional structure is 13.4% while that of the improved canister structure is 2.01%. The characters of the proposed canister FBG load cell are gained by tension experiment and temperature affection experiment. Furthermore, an experiment is carried out in a climatic chamber, and the results prove that the improved canister load cell can work properly in harsh environment.In order to improve the accuracy of the FBG load cell and reduce the number of FBG contained in one load cell, a novel'S'beam FBG load cell is proposed. In the load cell design, coupled dual-beam structure was adopted to achieve an accurate measurement, and the parts of FBG bonding are carefully chosen to withstand equal and opposite strain, which solved the problem of cross-sensitivity between strain and temperature of FBG sensing. Compared to the existing optical canister load cells used in icing monitoring, the coupled dual-beam structure load cell provides better accuracy, and the FBG numbers contained in one load cell decreased to two, which increased the monitoring areas through OPGW. Result from the tension experiment indicates that the accuracy of the 'S' beam FBG load cell is 0.863% which is much better than that of the canister FBG load celi. An icing environmental simulation experiment was carried out in a climatic chamber, and the results prove that the'S'beam load cell can work properly in harsh environment.A novel FBG tilt sensor is proposed based on beam of uniform strength. Compared with the existing tilt sensor, the proposed sensor has a better reliability. The relationship between FBG bonding part and the tilt sensitivity is investigated, and the results demonstrated that the FBG should be bonded near the end of the beam to obtain a better sensitivity and reliability. The results of tile angle experiment show that the proposed tilt sensor is sensitive to the tilt angel. An icing environmental simulation experiment was carried out in a climatic chamber, and the results prove that the tilt sensor can work properly in harsh environment.In this Dissertation, a novel passive anemometer was developed on the basis of the fiber Bragg grating (FBG) sensing technique. In the anemometer, a beam with uniform strength was used to measuring the force generated by the wind; two naked FBGs were symmetrical glued on the upper and lower surfaces of the beam to solve the problem of cross-sensitivity between strain and temperature of FBG sensing. Finite Volume Method was adopted to obtain the drag coefficient between wind speed and force applied on the anemometer. The results from wind tunnel experiment indicated that the anemometer had the advantage of lower non-linear error, and the measurement error was less than±0.5m/s. The startup speed of the anemometer is 3m/s.Last but not the least, an ice monitoring system composed chiefly of FBG sensors, OPGW, wavelength interrogator and softwave is developed to detect the ice accumulation on the overhead transmission lines. Tens of sensors distribute on 100km overhead lines can be transmitted by only one fiber in OPGW based on the Wave-Division Multiplexing (MDW). One of the most important advantage is there is no need of power supply near the overhead lines. Following the point mentioned above, the FBG sensors mount on the tower is immune to EMI which is important in monitoring in harsh electromagnetic environment. Further more, the FBG anemometers are only response to the Bragg wavelength and are rarely affected by the intensity of light.
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