ENHANCEMENT OF VOLTAGE STABILITY CONSIDERING EFFECTS OF WTG AND LOAD UNCERTAINTIES USING DIFFERENTIAL EVOLUTION

Namami Krishna Sharma, Aishwarya Varma, S. C. Choube

Abstract: This paper focuses on the improvement of voltage stability under the presence of various load uncertainties and WTG. Incorporation of WTG and ambiguous load variations are accounted here. The violation in stability limits due to uncertainties have been limited by designing the constrained objective function to improve voltage stability margin and in turn reduce active and reactive power losses. A multi objective problem is designed to minimize voltage deviation and power losses while satisfying the operating constraints, in order to enhance the system stability pertaining to uncertain environment. Primarily, a dynamic load flow program is formed to incorporate the data uncertainty at load buses. The adverse case affecting system stability is identified by the case having least Eigen value of the Jacobean matrix. L-index is calculated for all the buses of the identified case to decide the placement of Static VAR Compensator (SVC). The SVC operates as a control variable to enhance the systems voltage stability. Lastly, Differential Evolution (DE) Algorithm is used to obtain optimal value of SVC. The results are validated with the help of other optimization techniques namely, Black Hole Algorithm (BHA) and Particle Swarm Optimization (PSO). IEEE-14 bus system is used to implement the aforementioned problem.

Keywords: WTG; Uncertainty; L-index; Static VAR Compensator; Differential Evaluation

DOI: https://doi.org/10.15623/ijret.2018.0701009