BALANCE EQUATIONS OF INSTANTANEOUS POWER IN THE TASKS OF IDENTIFICATION PARAMETERS OF DOUBLE CAGE INDUCTION MOTORS

Currently, among the numerous induction motors double cage induction motors deserve special attention due to their widespread use in industry, as well as design features and processes work. Machines which use these engines are designed to operate in difficult conditions, so they often fail and come in for repair. As a result of repair operations elec-tromagnetic parameters are changed, which are needed for estimating the loss of energy, workers, and the starting char-acteristics, determining post repair passport of electric machine. One of the modern and the most effective methods for the determination of electromagnetic parameters of induction motors is the energy method, which is based on the bal-ance equations of harmonic components of instantaneous power at the source and at the elements of the equivalent circuit. The work presents equivalent circuit, which describes the processes in the working and start-up branches of double cage induction motor. There are relations shown for the active resistances of the rotor cages with their changes in the process of starting the motor and accounting the effect of the displacement current. There is a system received of balance equations of components of instantaneous power for the identification of the electromagnetic parameters of double cage induction motors and it is shown that the use of the energy method allows to obtain for this the required amount of equations.