Impacto dos harmônicos de tensão na temperatura e desempenho de motores elétricos classes IE2, IE3 E IE4.

Abstract

The introduction of new technologies as well as the improvement of materials and processes has contributed to accelerate the growth in the efficiency of the electric induction motors (IM). Currently in the market it is possible to observe the operation of IM classes IE3 and IE4, as well as minor efficiencies, in the same way proposals for IM class IE5 are being developed. This work aims to show the impact of 2nd, 3rd, 5th and 7th order voltage harmonics on the temperature and performance of IE2, IE3 and IE4 induction motor classes, the latter being a hybrid motor of permanent magnets and squirrel cage (Line Start Permanent Magnet Motor, LSPMM's). The measurements were divided into two stages, first feeding each of the motors with undistorted voltages and then entering each of the harmonics individually and in combination in percentages of 2% until reaching 25%. Considerable improvements in temperature, noise and consumption are notable in the case of the class IE4 hybrid motor, however, this motor also shows some weaknesses in its response compared to classes IE2 and IE3, mainly in the presence of harmonics. It is also presented as the presence of individual harmonics in electric motors, results in the appearance of other harmonics, according to the percentage of distortion present. Finally, in order to predict the variation of temperature in relation to the percentage of distortion, models representing this behavior were created, which represent good estimates of the temperature variation and the percentage of distortion inserted in the motor.