Correction to "Conducted Electromagnetic Emissions in Induction Motor Drive Systems Part II: Frequency Domain Models"

Predicting conducted emissions in pulsewidth modulation (PWM) inverter induction motor drive systems requires various frequency-dependent effects to be considered. A frequency domain method has advantages in such cases compared to a time domain approach. Based on the modal analysis presented in Part I, this paper develops frequency domain models to evaluate the spectra of the conducted emissions directly. The common and differential mode excitation sources are modeled in the frequency domain and related to the switching functions of the PWM inverter. Network models are established where the induction motor is represented using its frequency-dependent impedance characteristics, which can be obtained from measurements. The influences of system unbalances and of transmissionline effects due to long cables are investigated. Predicted emission spectra are compared with laboratory measurements and those derived from the time domain simulation. It is found that the agreement is good. The proposed method allows emission spectra to be predicted without recourse to specialist circuit simulators.

[1]  Tim Williams.  EMC for product designers , 1996 .

[2]  Li Ran,et al.  EMC measurements and simulation in variable speed drives , 1996 .

[3]  Li Ran,et al.  Conducted emission measurements in the power electronics environment , 1996 .

[4]  J. Roudet,et al.  EMI conducted emission in the differential mode emanating from an SCR: phenomena and noise level prediction , 1995 .

[5]  Thomas A. Lipo,et al.  Analytical estimation and reduction of conducted EMI emissions in high power PWM inverter drives , 1996, PESC Record. 27th Annual IEEE Power Electronics Specialists Conference.

[6]  Donald W. Novotny,et al.  The influence of winding capacitance on high frequency time harmonic losses in induction motors , 1992, Conference Record of the 1992 IEEE Industry Applications Society Annual Meeting.

[7]  Li Ran,et al.  Conducted electromagnetic emissions in induction motor drive systems. I. Time domain analysis and identification of dominant modes , 1998 .

[8]  J. L. Norman Violette,et al.  An Introduction to Electromagnetic Compatibility , 1987 .

[9]  Chu-Sun Yen,et al.  Time-domain skin-effect model for transient analysis of lossy transmission lines , 1982, Proceedings of the IEEE.

[10]  F. S. Merwe,et al.  Voltage harmonics generated by voltage-fed inverters using PWM natural sampling , 1988 .

[11]  Mark J. Nave,et al.  Prediction of Conducted Emissions in Switched Mode Power Supplies , 1986, 1986 IEEE International Symposium on Electromagnetic Compatibility.

[12]  S. Bowes.  New sinusoidal pulsewidth-modulated invertor , 1975 .

[13]  Li Ran,et al.  Conducted electromagnetic emissions in induction motor drive systems. II. Frequency domain models , 1998 .

[14]  Paul A. Lynn,et al.  Electronic Signals and Systems , 1987 .