Pantograph noise measurements in Madrid-Sevilla high speed train (AVE)

Ten years ago, the first Spanish high speed line which traveled from Madrid to Sevilla at an average speed of 250 km/h was inaugurated. At this speed pantograph noise, which is of an aerodynamic nature, is thought to have rather influence in the passengers zone. However, pantograph contribution is often omitted since main noise sources are expected to come from wheels and devices placed under the floor (motors, engines, compressors, etc). According to this, special anti-noise treatments are designed for floor structures achieving high noise insulation levels. Then, not expected noise contributions from the pantograph become significant. This paper is aimed at evaluating whether is necessary to apply anti-noise measures on the roof structure or not, by using the vibro-acoustical description of all car’s elements, and the measured pantograph sound power level as the inputs of a SEA model. Firstly, two microphone arrays had been used for the measurement, one of them having optimum microphone spacing to achieve best resolution at low frequency octave bands, and the other one to get best performance at high frequency octave bands, covering a global range of frequencies between 500 Hz and 4000 Hz. And finally, SEA model revealed the need of reinforcing roof insulation.