Structural Health monitoring of aged bridges：老龄桥梁结构健康监测.pptVIP

Structural Health monitoring with VibroFibre The application of VibroFibre TM Technology to measure Vibration and Temperature in the Stator End Windings (SEW) A presentation By Peter Kung QPS Photronics Inc Objectives Why you should know about the Static End winding (SEW) vibration problem Failure mechanism in the generator PD measurement Invention of VibroFibre TM and how it can eliminate such risks Fire damage on the end windingcan be quite sudden End winding Overhangs Vibrate at 2 x Synchronous Frequency Relationship between Vibration amplitudes looseness inside the generator Vibration comes from rotor/stator interaction Any looseness will increase the amplitude of this electro-magnetic force induced vibration Wedges that are not tight Windings are not tied down Cracks in any stator bar The end winding serves as a mechanical amplifier making it easier to measure Detecting these loose wedges used to require lengthy visual inspection Other options You can pay GE $300K to perform an automatic robotic inspection Good news is , it will help you locate looseness Bad news is it might not find any, but your money would already be spent! QPS Photronics and Peter Kung Company Expertise and history Invented The phase mask Technology Pioneered in Fiber gratings technology , product and process development Providing OEM products and solutions using fiber Bragg gratings technology In 2006 Peter Kung invented and patented a Fibre Bragg Grating structure VibroFibre? to measure vibration What is a Fiber Bragg Grating? Benefits FBG is small in size and light in weight Long operating life of 25 years Ideal for remote and distributed sensing FBG sensor is passive, draws 0 power Immune to RFI and EMI Can work in hostile environment, like extreme temperature and high voltages Design Structure By placing 2 such FBGs separated by a distance inside an optical fiber ,we will form a cavity, giving rise to interference fringes Vibration signal would modify these interference