Fast load shedding for angle stability control

This paper explores through simulation the speed of load shedding required for effective one-shot angle stability control. Experience with load shedding in China indicates that present technology is capable of shedding large amounts of load in approximately 0.1 second. An iterative, sensitivity-based procedure is used to find combinations of one-shot controls actuated 0.1 second after an event to stabilize transient events in simulation on a 176-bus model of the western North American interconnection. Some of these events require load shedding in addition to generator tripping and HVDC fast power changes in order to be stabilized. A response-based control scheme that uses apparent resistance R and its rate of change Rdot measured near the center of an intertie to trigger one-shot controls is tested with different actuation delays. The combination of controls ordered by the R-Rdot controller includes HVDC fast power changes and load shedding.