Voltage Profile Improvement Using DSTATCOM in Three-Phase Unbalanced Radial Distribution System

The distribution system (DS) is a multi-phase system with a high R/X ratio and operates in a radially or weakly meshed topology. For such a complex system, a reliable and effective load flow algorithm is necessary to carry out real-time operations, including network optimization, VAr planning, voltage profile improvement, and state estimation. The incorporation of FACTS devices like DSTATCOM can actually aid in the voltage profile improvement of DS. Therefore, this study attempts to verify the precision of the load flow algorithm in DS, which uses a forward-backward sweep (FBS) approach after incorporating a DSTATCOM for voltage profile improvement. The proposed approach includes a sensitivity analysis to locate the most sensitive buses on the three-phase unbalanced IEEE-33 bus radial distribution system/network (RDS). Further, the probabilistic reliability models are used to calculate the reliability at different load locations. Once the sensitivity analysis is done, the voltage profile of the unbalanced IEEE-33 bus system is improved by incorporating DSTATCOM at an optimal location in reconfigured DS. The proposed approach also enables the estimation of voltage magnitudes and voltage angles at each bus and power losses in DS. All the results are validated on the modified IEEE-33 bus and indicate a significant improvement in the overall voltage profile of the DS, especially the most sensitive buses identified by sensitivity analysis.