Parameter Estimating of An Equivalent Frequency Response Model of Synchronous Interconnected Power System Based on Cross-Section Information

Abstract

An equivalent frequency response (FR) model of sync-hronous interconnected system is of great significance to study the area frequency stability and virtual inertia control parameters design of renewable energy sources. Taking the cross section of transmission lines as the boundary, we can regard the concerned area and each external area as an equivalent generator respectively. In this paper, the interested area is considered to be known, then the equivalent generator of this area can be obtained by aggregation method. While for these external areas with complicated configuration and unknown parameters, how to identify the equivalent FR model is still a challenge task, which is the main motivation of this paper. Thus, a simple but effective method based on the local cross-section information is proposed to estimate the equivalent generators' inertia and primary control parameters of external areas. It should be noted that the proposed method can also be applied to estimate the FR model of the studied region. Combined with the aggregated FR model of the interested area, the completed FR model of the synchronous Interconnected power system can be constructed. Finally, an IEEE 5-area 68-bus power system has been modeled in PSCAD/EMTDC, and detailed transient simulation results have verified the method and associated analysis.