Online Thévenin equivalent determination using graphical phasor manipulation

This paper presents a new method for determining the Thévenin equivalent parameters of a power system at a node. A graphical method for deriving Thévenin equivalent parameters using online PMU measurements is developed based on representing and manipulating the measured voltage phasors in the complex voltage plane. The proposed method has the ability to use a large numbers of measurements for individual calculation thus providing greater tolerance of bad and erroneous measurements. The method is both computationally efficient and displays improved performance over similar methods when implemented using actual PMU data.