On the use of experimental modal analysis for system identification of a railway pantograph

Abstract

This study investigates the use of experimental modal analysis to identify the modal properties of a railway pantograph system, including component behaviour within the system, for an extended frequency range in three main directions. A pantograph was mounted in a laboratory with multiple accelerometers attached and excited at the collector strip by an actuator with a sine sweep method ranging between 0 and 200 Hz. A major portion of the numerical investigations into pantograph-catenary interactions have a frequency focus below 20 Hz. The results show that this method is well suited for system identification of the pantograph, highlighting the wide range of system and component frequencies to be considered when building a numeric model. The test results for the particular pantograph used in the experiment revealed important frequencies higher than the 20 Hz limit, at 22 Hz, 39 Hz and 62 Hz.