Improvement of power quality using UPFC in a multi bus distribution system

Abstract

The application of the unified power flow controller, UPFC, which is one of the flexible AC transmission systems devices, FACTS, to solve the voltage drop and to reduce power loss is developed. The IEEE 14-bus and 6-bus test systems are used for analysis using MATLAB Simulink software. Most of the power quality disturbances cause power loss increase in power systems. Among the power quality disturbances the voltage sag is the most common problem faced by the utilities. Moreover, the power loss reduction is one of the approaches considered by the utilities in their planning. In this research, two different situations are considered for both systems; without the application of UPFC device, and with the application of UPFC. The real and reactive power losses in the whole system are calculated for both situations, and the comparative results are provided. The system performance is also studied for different placement of the UPFC. In addition, the main capability of the UPFC which is injecting a variable voltage in series with the point of connection in network is examined and the power loss is measured in different injected voltages. The variation of the voltage is in the term of the voltage magnitude and phase angle. Simulation results have demonstrated that the application of UPFC has a desirable impact on power loss reduction in the power systems.