Voltage stability assessment using equivalent Thevenin

The voltage stability in the power systems operation has taken importance due to the restrictions in the network when there is a growing demand. This has motivated hundreds of researchers to develop methods to detect the voltage instability´s proximity, which reduces computational time and helps to take accurate decisions, guaranteeing a reliable and safe power systems operation. This paper presented the evaluation of different methodologies based on Thevenin´s theorem to transform large power systems in a simplified system of two-nodes. As an example, the methods are applied in a test-system of four-nodes. The results showed that one of the methods works properly in nodes of terminal load, transit and nodes of voltage controlled. The methodology proposed shows great potential for use in the Phasor Measurement Units (PMU) technology.