ESTIMATION OF APPLICATION EFFICIENCY OF LOW-FREQUENCY VIRTUAL SOURCES FOR ELECTROMAGNETIC PARAMETERS OF INDUCTION MOTORS IDENTIFICATION

The relevance of electromagnetic parameters identification of induction motors is due to the fact that they are counting starting performance, losses in steel and copper, determining the load capacity of electric machines. The reasons to change the parameters from designed by the manufacturer are: long-term operation, operation after repair and deviations in the manufacture of induction motors. Currently there are many methods, devoted to the identification of electromagnetic parameters identification of induction motors. However, there is no one single method that would be perfect for the identification of electromagnetic parameters identification of induction motors with different capacities and sizes terms in repair shops and electric repair enterprises. Modern methods of identification of electromagnetic parameters identification of induction motors can be developed through the use of power sources with the sine wave of amplitude-controlled voltage. Therefore, the purpose of the work is the development of method for electromagnetic parameters determination of induction motors using components of instantaneous power powered from sine wave sources. The use of components of instantaneous power in power balance equations allows us to develop the energy method, which is based on identification system of equations for electromagnetic parameters identification of induction motors. Feature of the energy method is that the balance equation are developing separately for each harmonics of instantaneous power for each element in the equivalent circuit of induction motors. Identification the electromagnetic parameters identification of induction motors has been invited to perform with the use of voltage and current frequency which is less than the frequency of the mains voltage, i.e. in the frequency range from 0 to 10 Hz. Have been to power of identification of induction motors suggested to use sinusoidal voltage source, and the desired frequency spectrum receive from the so-called ?pseudo source?. Pseudo source is a dummy source that is not physically, but only mathematically in the balance equation of power. Introduction of one pseudo source allows us to get a sufficient number of identification equations for determination of electromagnetic parameters identification of induction motors on a T-shaped equivalent circuit. Analysis of the results of using the energy method showed that the electromagnetic parameters identification identification error less than 5 %. Thus, the efficiency of using the energy method for electromagnetic parameters identification of induction motors identification using low pseudo sources has been shown.