High Power Inverter EMI Characterization and Improvement by Auxiliary Resonant Snubber Inverter

Electromagnetic interference (EMI) is a major concern in inverter motor drive systems. The sources of EMI have been commonly identified as high switching dv/dt and di/dt rates interacting with inverter parasitic components. The reduction of parasitic components relies on highly integrated circuit layout and packaging. This is the way to deal with noise path. On the other hand, switching dv/dt and di/dt can be potentially reduced by soft-switching techniques; thus the intensity of noise source is reduced. In this paper, the relation between the dv/dt di/dt and the EMI generation are discussed. The EMI sources of a hard-switching single-phase PWM inverter are identified and measured with separation of common-mode and differential-mode noises. The noise reduction in an auxiliary resonant snubber inverter (RSI) is presented. The observation of voltage ringing and current ringing and the methods to suppress these ringing in the implementation of RSI are also discussed. The test condition and circuit layout are described as the basis of the study. And the experimental EMI spectra of both hard- and soft-switching inverter are compared. The effectiveness and limitation of the EMI reduction of the ZVT-RSI are also discussed and concluded. The control interface circuit and gate driver design are described in the appendix. The implementation of variable charging time control of the resonant inductor current is also explained in the appendix.

Name thesis:degree_name

Master of Science

Level thesis:degree_level

masters

Discipline thesis:degree_discipline

Electrical and Computer Engineering

Department dc:contributor.department

Electrical and Computer Engineering

Grantor dc:publisher

Virginia Tech

Year dc:date.issued

1998

Author dc:creator

• Tang, Yuqing

Chair dc:contributor.committeechair

• Lai, Jih-Sheng

Committee members dc:contributor.committeemember

• Chen, Dan Y.
• Huang, Alex Q.

• soft switching
• noise reduction
• high power inverter
• EMI
• hard switching

Statement dc:rights

• In Copyright

Licence dc:rights.uri

• http://rightsstatements.org/vocab/InC/1.0/

Dc Identifier Other

etd-012299-165108

OAI identifier oai:identifier

oai:vtechworks.lib.vt.edu:10919/31022