Development of a fuzzy rule based generalized unified power flow controller

Rapid development of high power semiconductor devices with fast control features have given birth to several flexible AC transmission systems (FACTS) controllers to improve the power system performance. One of the advanced FACTS controllers is generalized unified power flow controller (GUPFC) or multi-converter UPFC, which can control bus voltage and both the real and reactive power flows of more than one line or even a sub-network. In this paper, dynamic performance of a GUPFC has been investigated using a new fuzzy logic based controller. The controller rules have been structured depending upon the relationship between the series inserted voltages in multi-line and the desired changes of real/reactive power flows in the power system. The effects of different types of controllers along with parameters of series transformers and transmission lines have been investigated through the control block models developed on a sample system in MATLAB SIMULINK. The effectiveness of the proposed scheme has been demonstrated through various case studies. Copyright © 2008 John Wiley & Sons, Ltd.