Abstract: As conducted noise frequency band of power convertor in electric vehicle is stricter than that in normal industrial equipment, a conducted noise simulation modeling method is needed which is suit for wide frequency range. A full-circuit conducted noise modeling method based on component model was proposed, in which high frequency dynamic characteristic was simulated by the active device model, complex impedance characteristic at full frequency band was described by the passive model, distributed parameter of bus structure and near-field coupling parameter were extracted to simulate their influence on coupling path of conducted noise. On the basis, full-circuit simulation platform for conducted noise of on-board DC/DC converter was built. Verification of simulated and measured result was realized at different duty cycle. It is shown that overall error between model simulation result and test result is relatively small, thus pre-evaluation for EMI is realized. And main source of errors at high frequency is determined by theoretical analysis.

Key words: conducted noise pre-evaluation, component level model, DC/DC converter, electric vehicle