Research on an Improved Model and Method of Calculating Total Transfer Capability

As a market signal concerned by all parties, transmission capacity has an important economic value in the competitive electricity market. Because of the present model and method´s shortage of calculating Total Transfer Capabiliy (TTC) based on Optimal Power Flow (OPF), which may either lead to shed load in some nodes under a feasible base-case power flow state, or could not reasonably deal with an unfeasible base-case power flow state, an improved model and method of calculating TTC based on DCOPF is presented. Aimming at the maximum nodal load increments, and introducing the load loss model, the basic idea of calculating TTC in this paper is adding the non-negative constraint in nodal load increments under a feasible base-case state, or transfering the unfeasible base-case state to feasible base-case state by load loss model. The IEEE-30 bus test system study results show that the proposed model and method are effective and practicable.