• Ch Sindhu
• P Rama Krishna

The Flexible ac transmission system (FACTS) technology is the application of power electronics in transmission systems. To understand and control the interactions between the FACTS devices based on VSCs and the utility system, there is a need for appropriate models to obtain fast and accurate results. There are several models of the FACTS devices based on ideal VSCs. The main purpose of this technology is to control and regulate the electric variables in the power systems. This is achieved by using converters as a controllable interface between two power system terminals. Two VSC models are proposed for the fast and efficient simulation of FACTS devices containing hard switched sinusoidal pulse width modulation (SPWM) VSCs. The power electronic circuit is modeled as a time-varying-topology network. This is a very useful approach at power system level. , power switching devices are modeled as ideal switches. In this paper, modeling of UPFC is performed based on sinusoidal pulse width modulation (SPWM) voltage source converters (VSC) and modeling of UPFC is performed based on Fuzzy Controller VSC. The UPFC is the most versatile device of the family of FACTS devices since it is able to control the active & reactive power respectively, as well as the voltage at the connection node. These models can be used to compute both the transient and the periodic steady-state solution of a power network containing VSC-based FACTS. The proposed Fuzzy logic based UPFC models have been implemented in MATLAB/Simulink software.

Distribution Generation, power quality (PQ), Active type SFCL.

"MODELLING OF FLEXIBLE COMPENSATING DEVICES USING FUZZY CONTROLLERS ", International Journal of Emerging Technologies and Innovative Research (www.jetir.org), ISSN:2349-5162, Vol.4, Issue 9, page no.201-208, September-2017, Available :http://www.jetir.org/papers/JETIR1709035.pdf

"MODELLING OF FLEXIBLE COMPENSATING DEVICES USING FUZZY CONTROLLERS ", International Journal of Emerging Technologies and Innovative Research (www.jetir.org | UGC and issn Approved), ISSN:2349-5162, Vol.4, Issue 9, page no. pp201-208, September-2017, Available at : http://www.jetir.org/papers/JETIR1709035.pdf