Three-dimensional rotor parameter modelling for dynamic performance analysis and rotor eccentricity identification in three-phase induction machines

This paper presents a novel approach to identifying rotor parameters and possibly rotor eccentricity in three-phase induction machines. The parameter determination method produces three-dimensional rotor parameters that are functions of both current and slip. The analysis is based upon the standard synchronous speed and locked rotor tests and several run up to speed tests at different supply voltages. Mathematical software is then used to estimate the parameters in the unknown regions of the three-dimensional look-up table, with current, slip and rotor resistance or leakage reactance values forming the axes. The simulated performance revealed that certain phenomena during start-up of the machine could be modelled by increasing the rotor leakage reactance momentarily. This indicates the possibility of identifying rotor eccentricity.