The paper deals with the substantiation of the prospects of the use of the methods and means for the thermal image control to determine the state of the internal structural units of electric machines with long time between failures. We determined the interrelations of the basic types of the structural unit defects with their thermal manifestation, which made it possible to formulate the special features and problems of the current thermal image control of electric machines under the operation conditions.
Słowa kluczowe: electric machine, structural unit, defect, thermal process, thermal image control.
Artykuł prezentuje uzasadnienie perspektyw użycia metod I środków sterowania obrazu termalnego w celu określenia stanu wewnętrznych jednostek konstrukcyjnych maszyn elektrycznych z długim czasem między awariami. Określono wzajemne relacje podstawowych typów defektów jednostek konstrukcyjnych oraz ich obrazowania termicznego. Umożliwia to sformułowanie specjalnych właściwości i problemów bieżącego obrazowania termicznego maszyn elektrycznych w specjalnych warunkach działania.
Keywords: maszyna elektryczna, jednostka konstrukcyjna, defekt, proces termiczny, obrazowanie termiczne
To provide the reliable operation of electric machines (EM) it is necessary to have trustworthy information about their current state . Its presence will enable both the assessment of their operation conditions and the forecast of the residual life for their timely withdrawal to repair or maintenance. In this case, the main problem consists in the impossibility to use many of the most accurate and advanced methods of diagnostics, as the current monitoring of EM condition is performed in most cases with operating equipment with limited access to EMs and their basic structural units . The above said substantiates the use of such methods of measuring, control and diagnostics that minimize the possible preparatory procedures and even eliminate their influence on operating EM, including various distant methods . According to the existing statistic data, most EM failures result from the winding or bearing units breakage preceded by the growth of their temperature. Thus, the diagnostic methods allowing additional assessment of the thermal condition of both separate units and EM on the whole are sufficiently informative [4, 5]. Their application is especially topical in the determination of the deviation of the temperature of the basic structural elements in complex dynamic operation modes and in the assessment of EM condition in the course of aging. The posed problem can be solved with the use of the methods and means of thermal image control (TC), along with the following digital processing of the obtained images. However, the problems of the accurate interpretation of separate sources of heating and the assessment of the intensity remain unsolved. The present paper settles these problems. Theory The direct application of TC to EM is a rather complicated and ambiguous problem nowadays. First, it is explained by the impossibility of the direct assessment of the state of the internal structural units as windings, cor [...]
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