With the increase of transmission voltage in HVDC system

the noise of converter station is becoming more and more serious. The filter capacitor in AC filter field is one of the main noise sources

and its noise reduction demand is higher and higher. In this paper

the noise simulation model of one capacitor is established by measuring the surface vibration and simplified

and then the noise simulation model of multiple capacitors is established. By using this model

four capacitors with different distance between bottoms are simulated and analyzed

and the noise power of the capacitors is lowest when the distance between bottoms is about odd times of the half wavelength.