On-line measurement-based model parameter estimation for synchronous generators: model development and identification schemes

Accurate generator modeling allows for more precise calculations of power system control and stability limits. In this paper, a procedure using a set of measured data from an online plant transient recording and analysis system to develop the synchronous generator model for the Taipower system is described. A continuous-time transfer function matrix is derived for a popular sixth-order synchronous generator model. In order to accommodate the nature of online digital measurements, the transfer function matrix is transformed into a simple discrete-time linear regression model. A measure of discrepancy between the generator model outputs and the online measurements from generators is employed. A modified conjugate gradient method suitable for identifying generator parameters is developed to minimize the measure of discrepancy, from which a set of accurate generator parameter values can be obtained. The merits of the modified conjugate gradient method include its computational efficiency and numerical reliability. The proposed procedure allows simultaneous estimation of all generator parameter values