Marginal Loss Modeling Based DCOPF and LMP Calculations for an Integrated AC and Multi-Terminal HVDC System

The objective of this work is to develop a framework for carrying out the locational marginal pricing (LMP) in a financially consistent manner for a generalized AC-DC system by considering the presence of multi-terminal high-voltage DC (MHVDC) links. Here, the financial consistency is sought in terms of having revenue adequate settlement within the multi-settlement framework in the presence of financial transmission rights. A suitable DC optimal power model is developed to perform the financially consistent locational marginal pricing for the generalized AC-DC system without compromising significantly with the power flow accuracy. Power losses in both the AC and DC networks are duly taken into account by using an upgraded version of the popular marginal loss modelling (MLM) approach. Apart from the incorporation of MHVDC links in the LMP based market clearing, provision is also created to receive bids and offers from entities that are directly connected to the DC network. Thus, separate sets of LMPs are generated for AC and DC networks in the AC-DC system. Ample case studies are performed with several differently sized systems to verify the effectiveness of the proposed MLM-based DCOPF framework for the LMP-based market clearing in a generalized AC-DC system.