Feasibility and Application Study of Optical Voltage/Current Sensors Using FBG

This paper concludes the case study work on the optical sensor, which is a new method for voltage and current measurement. Fiber Bragg gratings (FBG) have been developed and used for decades in the telecommunication industry. In recent years, FBG sensors have found wide applications in monitoring strain, temperature, voltage and current across all industries. As the process of constructing a robust smart grid, thousands of miles of optical-fibers have been deployed along the power transmission lines for the purpose of power production communication. This paper focuses on using the power optical fiber as voltage/current sensors instead of those copper wired traditional current transformers. By using piezoelectric layers, the optical sensor is able to transform voltage/current magnitude into optical signal, as well as transmit the signal through the optical fiber. The application of using optical fiber will significantly reduce the cost of deploying traditional current transformers all around the power grid. Moreover, the optical sensor is more stable, more accurate and faster, with such characteristics, the smart grid monitoring system could be much better. The application of combining the optical composite low-voltage cable (OPLC) and the optical current sensor in the distribution network for smart distribution monitoring has been analyzed.

A Passive Optical Fiber Current Sensor Based on YIG

A research on passive optical fiber current sensor based on magneto-optical crystal and a new design of light path of the sensor head are presented. Both methods of dual-channel optical detection of the polarization state of the output light and signal processing are proposed. Signal processing can obtain the linear output of the current measurement of the wire more conveniently. Theoretical analysis on the magnetooptical fiber current sensor is given, followed by experiments. After that, further analysis is made according to the results, which leads to clarifying the exiting problems and their placements.

Experimental and Theoretical Analysis of an Optical Current Sensor for High Power Systems

A magneto-optical sensor, using a dual quadrature polarimetfic processing scheme, was evaluated for current metering and protection applications in high voltage lines. Sensor calibration and resolution were obtained in different operational conditions using illumination in the 1550-nm band. Results obtained indicated the feasibility of interrogating such sensor via the optical ground wire （OPGW） link installed in standard high power grids. The polarimetric bulk optical current sensor also was theoretically studied, and the effects of different sources of error considering practical deployment were evaluated. In particular, the interference from external magnetic fields in a tree-phase system was analyzed.

Effects of Temperature on Weak Principal Axis of Twisted Fiber Loop

Theoretically and experimentally, the effects of temperature on the weak principal axis of twisted optical fiber loop are analyzed, and the results show that the location of the pair of weak principal axis will drift with temperature change, which will deteriorate the stability of system when applied to sensor system. In this paper, the influence of phase drift of weak principal axis on the performance of optical fiber current sensor is mainly predicted theoretically. Our research results will provide a beneficial reference for improving optical fiber sensor system.

Fiber structures and material science in optical fiber magnetic field sensors

Magnetic feld sensing plays an important role in many felds of scientifc research and engineering applications.Benefting from the advantages of optical fbers,the optical fber-based magnetic feld sensors demonstrate characteristics of light weight,small size,remote controllability,reliable security,and wide dynamic ranges.This paper provides an overview of the basic principles,development,and applications of optical fber magnetic feld sensors.The sensing mechanisms of fber grating,interferometric and evanescent feld fber are discussed in detail.Magnetic fuid materials,magneto-strictive materials,and magneto-optical materials used in optical fber sensing systems are also introduced.The applications of optical fber magnetic feld sensors as current sensors,geomagnetic monitoring,and quasi-distributed magnetic sensors are presented.In addition,challenges and future development directions are analyzed.