Optimal DG deployment to improve voltage stability margin considering load variation

The deployment level of distributed generation (DG) affects significantly the development of electrical distribution networks. These units could provide good benefits for the system provided that the optimal location and size of DG units are accurately defined. This paper presents a framework to obtain the optimal location and sizing of DG units to emphasize these benefits considering the load variation using genetic algorithm (GA) technique. A multi-objective function is developed based on improving overall voltage stability index (OVSI), enhancing voltage profile and reducing total energy loss. The main constraints involve a suitable voltage level at all buses, limiting the maximum number of DG units and limiting the total DG capacity. IEEE 33-bus typical system is used to test the proposed framework. The results indicate the possibility of improving the OVSI, enhancing the voltage profile and reducing total energy loss considering load variation using three formulas for VSI and different types of DG units.