Hagen Hertsch

Highly sensitive micro-mechanical fiber Bragg grating acceleration sensor combined with a new multiplexable interrogation principle

The paper describes a micro mechanical Bragg grating acceleration sensor with enhanced sensitivity by force amplification. A new multiplexable and affordable interrogation scheme that uses two overlapping Bragg gratings within the sensor will be demonstrated.

Investigation of stator coil and lead temperatures on high voltage inside large power generators via use of fiber Bragg gratings

This paper reports on the first realisation of embedding fiber Bragg grating temperature sensors inside the stator bars and onto the leads of a 200 MVA air cooled power generator. The worlds first measurements of the conductor temperature at high potential during a generator prototype test run demonstrates the feasibility and importance of this measuring technology.

Fiber Optical Temperature and Strain Measurements for Monitoring and Quench detection of Superconducting Coils

It has been demonstrated that Fiber Bragg Grating Sensors can measure at very low temperatures in Helium cryostats. The intrinsic temperature sensitivity is very low but can be significantly enhance by the thermal expansion of polymer carriers. Temperature and mechanical strain changes can be measured quite accurately.

Optical monitoring of highly stressed infrastructure and rolling stock modules for railway system operation

For the first time online temperature measurements with FBG temperature sensors on railway overhead lines could be demonstrated. All sensors measured successfully under outdoor conditions over a two year period. As a first experimental result the excess temperatures due to current load are small compared to ambient sources of temperature change. In the future this first result will be analyzed under different seasonal and current load conditions. Furthermore the modeling and first field test have demonstrated the possibility to acquire information about the interaction between OCL and current collector via optical strain gauges integrated into conventional current collector strips.