Generator Available Inertia Estimation Based on Various Disturbance Measurements of PMU

Abstract

Considering the inertia time-varying nature and its significance on frequency initial dynamics, it is meaningful to online real-time estimate available inertia with synchronous measurements. To avoiding the influence of neighboring connected systems on the inertia of specific concerned system, monitoring the system inertia is realized by estimating inertia of individual generator connected to it and aggregated them. Inertia estimation methods presented are swing equation based method with large disturbance measurements and system identification based method with ambient signals, which guarantee the accuracy and continuity of inertia monitoring respectively. The proposed generator inertia estimation system takes full advantage of effective information in PMU measurements, and achieves a useful input to adaptive protection and control application in a near-time way. The methods have been validated with the simulation of IEEE 39 bus system and PMU measurements in power grid in Shanghai, China.