Innovative concepts for on-line synchronous generator parameter estimation

A method to identify synchronous generator parameters from on-line measurements is presented. Generator parameters are employed in the construction of models used in transient stability studies and other routine power engineering studies. These studies are critical for the operation of the power system, and therefore accurate representation of synchronous generators and their parameters is important. The existing off-line techniques are often not practical and do not capture the behavior of the generator at all operating levels. Generator parameters vary due to aging, changes of the generator internal temperature, magnetic saturation, and coupling between the generator and external systems. The method proposed in this dissertation estimates generator parameters at any operating level, taking into consideration the effect of saturation and other phenomena in the operation of the synchronous generator.; Estimation of synchronous generator parameters is a fairly complex mathematical procedure, and there is a need for an easily used mechanism for model parameter estimation. The proposed method is based on least squares estimation and on a simplified synchronous generator model. The method is developed to be used with a Visual C++ engine and graphic user interface (GUI), so that the practicing power engineer may link machine measurements taken in an on-line environment with the estimator. A GUI application which is user friendly and self guiding is presented.; An observer for the estimation of damper winding currents is developed. The observer constructs estimates of the damper winding currents by using voltage and current measurements from the system and a priori system knowledge. The observer is integrated into the parameter identification algorithm.; A saturation model of the inductances of the synchronous generator is proposed and implemented in the estimator. Saturation affects a number of inductances in the generator. Accurate representation of saturation leads to accurate estimates that reflect the true status of the machine at every operating point. Saturation in both the direct and quadrature axes of the generator is considered.; Results from both simulated and actual measurements are presented. The feasibility of each of the proposed models is evaluated. Parameter estimation is performed for a number of generators at different operating points to enhance the confidence in the proposed algorithm. It is possible to use the proposed method to track generator parameters over time so that impeding internal generator faults can be detected and remedial action can be undertaken to avoid costly outages.