Abstract
Secure and efficient operation of an electricity transmission system has always been challenging. This has been further complicated by the recent growth in dispersed and intermittent power generation, connected to both transmission and distribution networks, along with the inherent intricacies of a detailed system. To represent this persistently growing vast and complex active distribution network in the transmission system, however modelled with limited number components; appropriate dynamic equivalent model is an essential necessity. In this paper, the entire distribution network for the Great Britain transmission system model (as operated by National Grid, UK) has been replaced with the proposed distribution system equivalent models following UK Engineering Recommendation G.74 standard. The analysis results of the initial AC and DC load flow study at winter peak demand scenario are presented. The aim is to comprehend the suitability of the network reduction strategy and dynamic distribution system equivalents for real time operation and for short term outage planning, and to realize the effectiveness and preciseness of the proposed approach.