Research On Application Of Unified Power Flow Centroller In HuNan Power System

Unified Power Flow Controller (UPFC) is the most powerful device in FACTS family, which can control the parameters of the power grid simultaneously, such as voltage, impedance, phase angel. It can expand the transmission capacity of line and improve the stability of the system. And the device has becoming a new focus in power system study.Firstly, this paper describes the development of Unified Power Flow Controller and its application, analyzes and discusses of its working principle and operation method, based on the above theory, using power injection method obtaine the mathematical model of UPFC and established UPFC’s steady-state model in Power System Analysis Software Package (PSASP) using for power flow control. The dynamic model of UPFC obtained by analyzing the dynamic process of UPFC, taking into account of its control objectives, and decoupling the system contained UPFC device basing on the d-q transformation, using power and voltage PI control as the control strategy. Then get the dynamic model of UPFC for stability analysis in PSASP. And then simulated in IEEE-14bus system, the results illustrate the model’s rationality and verify UPFC device have a strong regulatory function on power flow and transient stability.Give a theoretical analysis on sensitivity algorithms to confirm the optimal installation of UPFC, and then combine with the concrete condition of Hunan power grid to determine the installation location of UPFC. Hunan power system has such issues as uneven distribution of power flow and line capacity limits problem. In older to solve those troubles, access UPFC to the system and simulated. We can get the ideal line power flow by setting appropriate control parameters, the transmission line capacity limit also increased. For voltage stability problem, determined the install location of UPFC device though analyzing the concrete condition of Hunan power grid, and then simulated, simulation results show that the voltage of each line can maintain stability, the voltage stability problem solved perfectly and increase stability of Hunan power grid.