It is rather important to predict transient stability quickly and accurately after a powersystem has been subjected to a severe transient disturbance. The Wide Area MeasurementSystem (WAMS) has the ability to record dynamic behavior of a power system in a real-timeway with the same time mark. This offers a new platform for power system transient stabilityprediction.In this thesis, some new methods are proposed to predict transient stability in thepost-fault period in a power system, based on the WAMS information. Firstly, the SpeedDeviation Derivative Method and the Imbalance Power Method are put forward to forecasttransient stability in a One-Machine Infinite Bus (OMIB) system. Secondly, leadinggenerators are selected according to the angle, speed deviation and acceleration of eachpost-fault generator. Finally, a new method that is called the Equal Electrical Power Methodis used to get the equal P-δ curve in a multi-machine system, after it is changed into a OMIBsystem using the Extended Equal Area Criterion (EEAC) methodology, without thehypothesis that the turbine mechanical power should be constant. The simulation resultsprove that the methods can predict transient stability of a power system quickly andaccurately.
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