Identification of armature circuit and field winding parameters of large utility generators

This paper presents a methodology to estimate armature circuit and field winding parameters of large utility generators using both the synthetic data obtained by the machine natural abc frame of reference simulation and real time operating data of a utility generator. A one-machine infinite bus system including the machine and its excitation system is simulated in the abc frame of reference by using parameters provided by the machine manufacturer. A proper data set required for estimation is collected by perturbing the field side of the machine in small amounts. The recursive maximum likelihood (RML) estimation technique is employed for the identification of armature circuit parameters. Subsequently, based on the estimates of armature circuit parameters, the field winding and some damper parameters are estimated using an output error estimation (OEM) technique. For each estimation case, the estimation performance is also validated with noise corrupted measurements. Finally, the developed methodology is used to identify an actual utility generator parameters from on-line operating data.