The noise of AC filter capacitor installation is one of main noise sources in converter station

which mainly comes from vibration of capacitors shell and the corona discharge of grading rings.Therefore

calculation of corona noise level has great significance to the study and for reasonable estimation of the noise level of the whole capacitor installation.In this article

the predictor formula of finite length line sound source and point source is deduced from the audible noise predicting formulas recommended by BPA for AC transmission lines.Depending on structural dimension of 500kV A.C filtering capacitor installation

the electric field is calculated by ANSYS to get the corona noise level on the surface of grading rings and the lead end of capacitors with maximal electrical field strength as assessment base of corona noise of capacitor installation.The results show that the predictor formula could get more ideal result

and the corona noise level reduces in the exponential function with the reduction of electric field in surface structure and the rise of measuring distance.