Matlab-based voltage stability analysis toolbox and its validity check

A novel Voltage Stability Toolbox(VST) is introduced, which is programmed using Matlab math language, and the features of its open source code and a complete set of user-friendly graphical interfaces are detailed. It implements standard Newton-Raphson (NR) and Newton-Raphson-Seydel (NRS) convergent algorithms to analyze the voltage stability and bifurcation of power system. The main functions of VST include power flow, time domain simulation, singularity analysis, eigen-analysis, as well as static and dynamic bifurcation analysis. VST is a very helpful tool to understand voltage stability and nonlinear bifurcation phenomenon. Test results of the application of this toolbox in a five-bus system with three generators and 30-bus test system are presented to show the practicality and effectiveness of the VST.