Fiber optic Fiber Bragg grating sensing for monitoring and testing of electric machinery: current state of art and outlook

This paper presents a review of the recent trends and the current state of the art in the application of fiber optic fiber Bragg Gratings (FBG) sensing technology to condition monitoring (CM) and testing of practical electric machinery and the associated power equipment. FBG technology has received considerable interest in this field in recent years, with research demonstrating that flexible, multi-physical and electromagnetic interference (EMI) immune in-situ sensing of a mul-titude of physical measurands of CM interest is possible, that can not be obtained through con-ventional sensing means. The unique FBG sensing ability has the potential to unlock many of the electric machine CM and design validation restrictions imposed by limitations of conventional sensing technuques but needs further research to attain wider adoption. The paper first presents the fundamental principles of FBG sensing. This is followed by a description of recent FBG sensing techniques proposed for electric machinery and associated power equipment and a dis-cussion of their individual benefits and limitations. Finally an outlook for further application of this technique is presented. The underlying intention is for the review to provide an up to date overview of the state of the art in this area and inform future developments in FBG sensing in electric machinery.
Keywords: Fiber Bragg grating (FBG); Fiber optic sensors; Electric machines; Drives