Investigated both static and dynamic modes of operation of an asynchronous electric drive and a comparison of the performance characteristics of a adjustable induction motor, obtained theoretically and experimentally. Values of the parameters used in modeling static modes of operation and in solving a system of nonlinear equations describing dynamic modes of operation were determined by analytical expressions and also as a result of field analysis and were used in the DIMAS Drive program.Field analysis is based on the calculation of the electromagnetic field by the finite element method using the JMAG software.
When analyzing the operation of a regulated asynchronous motor, it was taken into account that the nonlinear coefficients of the equations (equivalent circuit parameters), as well as the losses in the magnetic core steel, the additional and mechanical losses vary at each step of integration of the system of differential equations.When calculating the dynamic characteristics, the nature of the load is taken into account, namely, at each integration step the change in the load moment is taken into account. The form of the dynamic characteristics is also affected by the moment of inertia of the drive and the rate of increase in the control parameter- the frequency of the converter.Therefore, in calculating the dynamic modes, changes were taken into account at certain points in the characteristic of the transition from one speed to another, the values and frequencies of the supply voltage. The loss was determined in the analysis of static regimes. Taking into account the above-mentioned component losses, it was possible to clarify the calculations of the energy parameters in transient regimes.When using the equivalent circuit parameters obtained from the results of the field analysis, the error in calculating the performance characteristics with respect to the experimental studies is reduced in comparison with the calculations in which the equivalent circuit parameters are determined by analytical expressions.