Field evaluation of efficiency and prediction of steady state performance for induction motors based on equivalent circuit methods

The work proposes a method for field evaluation of efficiency and prediction of steady state performance for conventional as well as for converter fed induction motor drives, based on equivalent circuit methods. The motor parameters are measured by means of a standard PWM frequency converter and a universal analyzer with a Fourier analysis function, for direct reading of both total and fundamental RMS values of voltage, current and power. The results coincide well with the efficiency and steady state performance graphs obtained by direct measurements in the laboratory