Determination of Total Transfer Capability Incorporating FACTS Devices in Power Markets

It is very important and necessary to calculate total transfer capability (TTC) incorporating flexible alternate current transmission system (FACTS) devices in power markets and analyze impacts of FACTS on TTC. Calculating TTC incorporating with FACTS devices is an optimal problem constrained by some equalities and inequalities. This paper proposes a mathematical model for calculating TTC incorporating with FACTS devices in power markets, and detailed calculation method is also put forward. The constraints include voltage constraints, thermal stability limits, generator´s capacity limits, load demand, steady-state power flow, and control parameter constraints of FACTS devices, etc. The sensitivity-based repetitive linear iterative approach is proposed to solve the proposed model. The detailed solution process is described in this paper. To realize the proposed model and calculation method, a TTC calculation software incorporating with FACTS devices is developed based on PSASP/UPI, a set of advanced application software package developed by China Electric Power Research Institute. This paper proposes a new approach on combined TTC solution including FACTS and power flow calculation based on PSASP/UPI, and gives the interface program for user programming interface (UPI) in PSASP. The IEEE 14-bus test system is used to verify the proposed algorithm and program. Numerical results show that FACTS devices and their locations have different impacts on TTC, also prove that the proposed model and algorithm is correct and effective