Measurement of torque harmonics of a cage induction machine under rotor eccentricity

Eccentricity creates an unbalanced magnetic pull in the rotor of the cage induction machine which plays a vital role in the rotordynamic stability. In this case, it is desirable to know how different quantities of the machine behave, for example torque. Numerical analysis shows an increase in the average torque of the machine with eccentricity. The amplitudes of some of the harmonic components of the torque are also affected. In such case, the measurement of the torque waveform could give a good insight to the behavior of the torque and its harmonics. Here, a novel measurement rig is presented.