Optical sensors for the analysis of pantograph-catenary interaction

In the present paper, the advantages of the use of optical sensors, and in particular sensors based on FBG (Fibre Bragg Grating), for the analysis of dynamical interaction between pantograph and catenary are discussed. The experience of a real application where FBG sensors were used on a pantograph of underground vehicle is presented and the related experimental results are discussed. Optical sensors are very suitable for the analysis of pantograph-catenary interaction because they are intrinsically electrically insulated and insensitive to the electromagnetic disturbances and they do not need electrical power supply: these features make the optical measurement setup very simple with respect to the electrical measurement setup for the particular application. This paper aims at presenting the main features of FBG sensors and at comparing performances of optical sensor and traditional electrical sensors by means of results of experimental tests performed to analyse the interaction between pantograph and catenary for an underground line. The experience discussed in this paper shows that the use of an optical measurement setup for the analysis of pantograph-catenary interaction takes to an important simplification with respect to the traditional measurement setup with electrical sensors.