METHOD FOR PREDICTING ELECTROMAGNETIC NOISE IN INVERTER INDUCTION MOTOR SYSTEM

摘要

PROBLEM TO BE SOLVED: To predict the voltage level of electromagnetic noise being generated actually in an induction motor through harmonic analysis of load current by measuring the electromagnetic noise-harmonic current characteristic table of an induction motor. ;SOLUTION: A commercial power supply of 50 Hz generates a sine wave voltage as a first means 1, an inverter generates a single harmonic as a second means and a transformer T applies a combined voltage of the sine wave voltage and the single harmonic voltage to an induction motor as a third means 3. A harmonic current flowing through an induction motor 7 is controlled by controlling the output frequency of the inverter. Amplitude of the harmonic current can be regulated by regulating the voltage of input DC link of the inverter through a voltage slider S. The voltage of input DC link of the inverter is regulated through the voltage slider S such that the harmonic current has a constant amplitude while varying the frequency of the single harmonic voltage or the current.;COPYRIGHT: (C)1998,JPO