Distributed Optical Fiber Sensor Technology And Utilizations In Smart Grid

Based on the temperature and strain measurement of the cable and transformer winding in Smart Grid, this thesis discuses Fiber Bragg Grating temperature sensor system, distributed Brillouin Optical Time Domain Reflectometer temperature and strain sensor system and distributed Brillouin Optical Time Domain Analysis temperature and strain sensor system. Each chapter introduces the applications, principles and the advantages and disadvantages of each system at the same time proposes a novel patent or utility model design of an improved structure to get a simpler composition, higher cost-effective or better performance. Besides, this thesis obtains the confirmation of the feasibility of optical fiber sensor system used in Smart Grid by experiments.In order to get better spatial, temperature and strain resolution, this thesis presents a novel temperature and strain sensor system based on distributed Brillouin Optical Time Domain Analysis. Furthermore, because of the special requirements of the light source in such system, this thesis presents and simulates a novel narrow linewidth DFB laser based on micro-ring external cavity, using weak coupling and low loss to obtain an output linewidth about 88 kHz. In order to realize a wider wavelength scanning range and a possibility to scan both in rough and precise mode, the novel frame utilizes the vernier effect of two micro-ring array to get a nearly 88 kHz linewidth, about 62nm scanning range and a rough/precise scanning mode. Finally, this thesis presents an integrated chip design consisted of two narrow band DFB lasers and an optical delay line, using InP as its substrate. Owing to the high integration of micro-ring, this design can be used to reduce the cost of BOTDA commercialization.