Voltage Stability Assessment on Ethiopian 230 KV Transmission Network Using Modified Voltage Stability Indices

This paper presents a method for performing voltage stability analysis and ranking of network buses using user-modified voltage stability indices (MVSI). In the study, Ethiopian 230 KV power system is modeled and Newton Raphson power flow analysis is carried out using power system stability analysis toolbox (PSAT). In this analysis, base load data is used to determine the steady state power flow solution. To account for loading effects on bus voltage stability, the load reactive power is increased to its maximum stability limit and modified voltage stability indices determined. Buses are ranked in descending order based on their load voltage stability severity using modified voltage stability indices. The results show that the modified voltage stability index techniques is effective for ranking of load buses in meshed power networks compared to conventional methods.