Hottinger Brüel & Kjær (HBK) has developed a measuring system for pantographs named Fibre Bragg Grating (FBG), which is used for the maintenance of overhead line systems in rail transport. The system monitors forces and accelerations under high voltage in the pantograph structure in order to minimise damage to the overhead line. If a critical condition is detected, the system immediately sends out warnings to prevent unexpected delays or system failures. HBK's FBG system provides safe, continuous measurements in a high-voltage environment using its optical fibre. The optical sensor is a passive element whose measuring principle is based on light and does not require active excitation of the sensors. This means that there is no interference with other operations during the measurement. The FBG system also ensures compliance with the EN 50317 standard, which measures the interaction between the pantograph and the overhead contact line. Operators must fulfil this standard to ensure minimal losses, limited wear, and a reduced risk of interference during power transmission to the vehicle unit.
