Діагностика кутового ексцентриситету ротора асинхронних двигунів на основі аналізу віброзбуджуючих сил

Abstract

Методами математичного моделювання досліджено зміни величин і характеру електромагнітних віброзбуджуючих сил, які виникають при появі кутового ексцентриситету ротора асинхронного двигуна. Досліджено допустимі діапазони величин кутового ексцентриситету, при яких можлива подальша експлуатація машин без обмежень. Показано, що для забезпечення процесу вібраційної діагностики кутового ексцентриситету потрібно використання двох датчиків, які розташовані на протилежних торцях осердя статора двигуна в одній площині.

Rotor angular eccentricity of induction motor is damage, which should be investigated in a three-dimensional setting, because the value of air gap varies along the length of induction motor, which requires significant computational power of computers. However, in order to simplify the analysis of vibroperturbing forces, it can be analyzed in two-dimensional planes staged as a set in which the rotor is shifted relative to the stator in the radial direction. Vibration sensors located on the surface of the stator, take off diagnostic information in only one of these planes. Sensor signals are located in one plane at different ends of the stator core. So enough to explore displacement of the rotor relative to the stator in a two-dimensional formulation of these two planes. Diagnostic signs of angular eccentricity appearance, which can be used in systems of vibrodiagnosis, were determined: a significant increase in noise and rotary teeth harmonics spectrum of vibroperturbing forces in one of the sensors, which is located in the zone of minimum air gap of induction motor; the absence rotational harmonics in vibroperturbing forces spectrum. Permissible range of angular eccentricity values at which there is possible further using of machines without restrictions were investigated. It is proved that the rotor angular eccentricity is dangerous kind of damage due to the appearance of longitudinal torque of force, which leads to accelerated wearing of motor bearings.