Parameter estimation for induction machines based on sensitivity analysis

Induction machine parameters supplied by manufacturers are usually sufficient for short-circuit analysis only. System studies that involve transient simulation of machines require additional parameters that are not readily available, but nonetheless are essential for an accurate modeling of the machines. A mathematical method for estimating the equivalent circuit parameters of induction machines from the most readily available performance characteristics is presented. In this method, machine equations are used to estimate the parameters and sensitivity analyses are then performed with respect to the circuit parameters to match the given performance characteristics. An example is included to illustrate how well the performance of the estimated model matches that of the actual machine. The example is a three-phase, 1000 HP, 4.16 kV, 60 Hz induction motor. The example indicates that, with a restricted set of input data, it is possible to find the elements of a machine model that duplicates the given performance to a high degree of accuracy. Without sensitivity analysis, accuracies on the order of 10% are obtained, but after sensitivity analysis an accuracy of 0.1% or better can be achieved