Voltage stability analysis of unbalanced distribution systems with wind power penetration

This paper presents a new method for voltage stability analysis of unbalanced distribution systems connected with wind turbine energy systems (WTGSs). The developed continuation power flow uses secant predictor technique. The predicted solution is corrected using a radial power flow solver. The advantage radial load flow solver is interesting as it contains no matrices and hence it avoids the singularity found in Jacobian matrix. The WTGSs has been modeled based on sequence components. The developed model accounts for distribution system unbalance with the slip as independent variable which has been calculated during the power-flow solution process. A 33-node balanced feeder and The IEEE 13-node and 123-node distribution feeders with/without wind penetration are used to test out the developed method. Different case studies are used to test out the effect of WTGSs on both voltage profile and stability of unbalanced distribution systems.