Assessment of the influence of distributed generation and demand side management on transmission system performance

All relevant studies indicate that future electricity networks will see a significant increase in renewable-based distributed generation (DG) and much wider application of load management and intelligent network technologies. The impact of DG and demand-side actions is direct and easily observed in the distribution networks. Their effects on transmission system performance, however, are more difficult to assess and quantify. Accordingly, this paper attempts to assess the impact of DG and demand side management at the sub-transmission and transmission levels, where realistic models of DG (including micro and small-scale DG) and improved aggregate load models (incorporating models of demand-manageable loads) are connected to network. The propagation of harmonics from distribution to transmission networks due to a substantially increased contribution from inverter-interfaced DG and modern non-linear loads is also discussed in the paper.