Mitigation of EMI generated by a variable frequency drive controller for an AC induction motor

In recent years a significant number of digital devices and systems have been added to receiving and data-processing sites. These additions have enhanced the ability of the sites to accomplish their mission. They have also introduced new kinds of electromagnetic interference (EMI) into these sites along with accompanying performance degradation problems. In this thesis one specific case of EMI is considered. It is EMI from a digital climate-control system of a building housing a data-processing facility. The digital system generated excessive amounts of EMI. The EMI was conducted throughout the site over power and control conductors. Electromagnetic fields from EMI current flowing in these conductors coupled the EMI into other nearby conductors. Integrated barrier, filter, and ground techniques were used to reduce the conducted and radiated EMI to harmless levels.http://archive.org/details/mitigationofemig1094543034U.S. Army (USA) authorApproved for public release; distribution is unlimited