Full-scale experiments on the active noise control in high-speed train carriage

To reduce the low frequency noise in the carriages of high-speed trains, the active noise control inside the carriage is studied. A 48-channel feedforward active control system is designed based on the measured noise spectrum of the high-speed train and the size of the target area (1.8 m × 2.5 m × 1.3 m). The secondary sources are placed around the target area and the error sensor positions are distributed in the target area. The control filters are calculated based on the measured acoustic transfer functions. The experiment is carried out in one carriage in a semi-anechoic room, in which the sound field reproduction system outside the carriage is used to generate the primary noise. The influence of different primary noises and reference signals on noise reduction performance is analysed. It is shown that for the primary noise at different train speeds, an average noise reduction of 3.1~4.7 dBA can be obtained at 48 measurement points in the target area, with the vibration signal acquired from the cabin window as a reference signal.