Power System Voltage Stability Based on Optimal Size and Location of Shunt Capacitor Using Analytical Technique

This paper studies an assessment of power systems voltage stability with and without a shunt reactive power compensation device such as a capacitor bank. To allocate the shunt capacitor, a voltage stability index (VSI) is utilized to discover the highly sensitive bus for allocating the shunt capacitor in the system. The best capacitor size is calculated using the minimum power loss technique which gradually rises in the capacitor reactive power to obtain the minimum power losses. The influence of the shunt capacitor on the power system voltage stability is studied using the voltage stability analysis with tracing of the PV curve. In this work, the IEEE 9-bus system is used and modelled in Power World Simulator tool. However, the capacitor location and size calculations are performed by MATLAB M-file environment. The results show that the shunt capacitor improves the voltage stability by injecting the proper reactive power.