Title :
Losses in three-phase induction machines fed by PWM converter
Author :
Hildebrand, E. Nicol ; Roehrdanz, Hagen
Author_Institution :
Inst. of Elektrotechnisches, Tech. Univ. Dresden, Germany
fDate :
9/1/2001 12:00:00 AM
Abstract :
The paper deals with the analysis and evaluation of test results of PWM converter-fed induction motors. The test results presented point out the dependency of the harmonic losses on the pulse frequency. The measured values were obtained by means of a novel high precision power-analyzer capable of measuring the harmonics of voltage, current and power. Following a detailed investigation regarding the sources of the harmonic losses the paper describes new methods for determining the harmonic losses by both calculation and measurement. The calculation is based on a new equivalent circuit comprising specific impedances for imaging the eddy-current circuits within the iron core derived from the fundamental equations of the three-phase asynchronous machine. These impedances permit the calculation of the harmonic iron losses under the influence of the eddy-currents in all sections of the magnetic circuit caused by the harmonics. Measured and calculated losses were found to correspond satisfactorily for the various voltage harmonics
Keywords :
PWM power convertors; asynchronous machines; eddy currents; electric current measurement; equivalent circuits; harmonics; losses; machine testing; machine theory; magnetic circuits; power measurement; voltage measurement; PWM power converters; current harmonics measurement; harmonic losses; power harmonics measurement; pulse frequency; test results; three-phase induction machine losses; voltage harmonics measurement; Current measurement; Impedance; Induction machines; Iron; Loss measurement; Power measurement; Pulse width modulation; Pulse width modulation converters; Testing; Voltage;
Journal_Title :
Energy Conversion, IEEE Transactions on
