Study Of Voltage Source For A Model Of Unified Power Flow Controller

The Unified Power Flow Controller (UPFC) is regarded as the most versatile FACTS (Flexible Alternate Current Transmission System) device, its attractive performance is that the Unified Power Flow Controller can control rapidly line power flow, increase system transmission ability, damp the oscillation and improve the power system transient stability.Now, many FACTS facilities, mainly including STATCOM & SVC, have been put into industrial application. However, UPFC, which can fully control the voltage, impedance and phase of the transmission line and is regarded as the most promising member of FACTS family, has not been used widely. Most researchers' interests concentrate on theoretical analysis and simulation. In order to study UPFC's practical regulation ability, it is necessary to make a physical model, which can also help researchers verify their control strategies and fully understand its characteristics.In this paper, the hardware design of a 10k VA UPFC model and the function of each part are introduced detailedly, the principles and controllable ability of UPFC are analyzed by theoretic methods. The IGBT inverter bridge adopts SVPWM technique, which is of high utility of DC bus voltage. The voltage source of UPFC is analyzed mainly. The mathematical model of voltage part is set up and amended. Under the principle of brief and practical, the Dead-Beat control and sine statble error compensator are adopted, the simulations are given in this paper show that this designed controlling method can not only effectively respond to step input, but also completely compensate the sine statble error. Thus, this designed controlling method in this paper is effective.