An Effcient Noise Source Impedance Estimation Approach Applied in Electromagnetic Compatibility

In conductive electromagnetic compatibility, the estimation of noise source impedance like switchedmode power supply's impedance is somewhat a troublesome problem since it is uneasy to detect the internal noisesource impedance and also this impedance may vary quitedifferently due to the various type of sources. In this paper an effcient estimation approach of conductive noisesource impedance is presented where single current probemethod in conjunction with fast Hilbert transform methodis employed for amplitude characterization and phase characterization of source impedance, respectively. The principle and application of this approach are described, andsome experiments are accomplished to verify the approach.