Available Transfer Capability Study Of Power System Based On Voltage Stability

In a interconnected power system, Available Transfer Capability is not only a technical target, but also can reflect transfer capability of network. It is playing fully positive role on guiding the market transaction, using transmitting capability and so on .Therefore, the problem of how to ascertain power system transmission capability of areas accurately and the facts that have effect on it within the restrictions of safety and reliability, and how to maximize the loading on existing transmission systems have become the urgent problem of modern power systems.The basic conception of ATC is introduced in this paper. This paper establishes CPF model of power system and caculates saddle-node bifurcation of the system. Thus we obtain load increment and state variables of system corresponding Saddle-Node Bifurcation and obtain voltage stability feasible region of system ;in this feasi-ble region,the paper uses the OPF modle to calculate the avalible transfer capability considering static state reliability.The effectiveness of the presented model and approach is supported by the tests on a sample system, and the results show that it have pr-eferable convergence and capability of handling the inequality in the optimal problem.