SMALL SIGNAL STABILITY ANALYSIS OF MODERN POWER SYSTEMS

Abstract

This dissertation deals with two aspects of small signal analysis of the power system: placement of power system stabilizers (PSSs) and line outage screening based on estimation of the elgen values using sensitivities. A PSS is an instrument installed in a generator to stabilize the power system. From a system wide point of view, PSSs are used in order to stabilize the power systems when the demand for power increases and thus more power is delivered over longer distances. From a design point of view, a PSS is a device used to increase the damping torque component of a machine. Although a PSS can be installed at every machine, only a few PSSs are needed to stabilize a power system. The effect of PSSs placement is an analogy to find which PSS has the most effect on a particular mode in a system. This information is used for determining which PSS should be turned on. The Eigen value tracking (ET) method for the PSS placement is being presented here. This method makes a connection between the interconnected power systems model and decoupled system model which comprises of single machine infinite buses (SMlBs).