Application of synchrophasor angular difference as a grid monitoring tool and for assessment of Real time voltage Stability-Case Study

This paper investigates about the application of Synchrophasor angular difference for detecting the various grid events which allows operators ease and advancement for grid monitoring. This paper explains the real time grid events and cases observed in eastern regional grid, where Phase angle difference has been used as a grid monitoring index for monitoring and sensitizing the grid stress. Synchrophasor angular difference used for predicting voltage collapse in collaboration with PV curve obtained from PMU, in real time which is very much effective and specially effective for weak nodes with low fault level and nodes with skewed/variable generation pattern. Monitoring Angular difference is of very much importance as system stress can be identified easily, under all set of different scenarios and contingencies. To enhance the situational awareness of grid operators, path flow monitoring along with the angular difference of the path is used for defining operating state of a particular corridor/area of the power system, whether operating in normal, Alert, or emergency state so that with corrective action system can be brought back to normal state. Path angular difference gives an upper hand and can predict about voltage collapse events beforehand and also margins to the knee point can be accessed in terms of angular difference of the path. In real time with the help of synchrophasor data, real time reserve monitoring for the identified path/area can be done so that sufficient margin can be maintained for contingency situations.