Comparative study of voltage stability enhancement of a grid and loss reduction using STATCOM and SSSC

The higher demand for electric power and poor reactive power management has led to voltage stability problems in power system. The voltage instability of a power system is mainly caused due to some disturbance occurring at some location, due to which rapid voltage drop occurs. This voltage drop can turn cumulative and finally lead to voltage collapse. In this work the voltage stability analysis is performed on the test system to evaluate the influence of FACTS devices on improving the voltage profile of the system. The optimal location for the installation of the FACTS controllers is obtained using the line stability index Lmn and validated using power flow analysis. A comparative study is conducted to select the best FACTS controller in terms of voltage stability. The WSCC 9-bus system is taken as the test system. Simulations are done in MATLAB/PSAT environment. From the simulation results it has been found that with the optimal implementation of FACTS controllers the voltage stability of the power system was improved and the real power losses in the system was reduced considerably.