Modeling and simulation of a Kalman filter based control scheme for an AC/DC power system

This paper presents the development of a Kalman filter (KF) based control scheme to improve the dynamic performance of a parallel AC/DC transmission system. The control algorithm is based on proportional-integral (PI) feedback control of thyristor firing angles in the AC/DC and DC/AC converters using KF estimates of system parameters as inputs. The work has two motivations. First, to avoid a control scheme designed by trial-and-error only, since the physical consequences of catastrophic control loss in power systems makes such approaches difficult. Second, to include physically important effects often left out of models for such systems as a mathematical convenience. Such factors include, AC line interactions, the coupling of the generator controller to the HVDC controller, reactive power effects caused by thyristor operation, frequency dependent transmission line and noise effects. PSCAD/EMTDC based simulations are presented and discussed for a number of contingencies, and conclusions drawn for future work. (C) 2004 Elsevier Ltd. All rights reserved.