The present study deals with the optimal capacitor placement problem in the radial distribution systems using the optimization techniques. The technique utilizes two stage procedures in order to identify the best capacitor location and sizes. In first phase, the loss sensitivity analysis is carried out using two sensitivity indices to obtain the most candidate capacitor locations along the distribution line. Further, the particle swarm optimization is adopted to find the optimal locations as well as its size. The objective function is formulated in such a way to minimize the power loss and capacitor cost. In this optimal placement study, different capacitor modules such as fixed, switched and its combinations are considered for analysis.
The backward/forward sweep algorithm is developed to perform the load flow calculations and the proposed method is tested on the IEEE 34 and 85 bus distribution systems. Moreover, the performance studies are also performed on a real distribution system of the east delta network to validate the feasibility. From comprehensive study, it has been inferred that the proposed procedure achieved significant savings in the system total cost. Further, in comparison with other methods, the proposed scheme is found to be suitable for big distribution systems and can considerably improves its performance.

The present study deals with the optimal capacitor placement problem in the radial distribution systems using the optimization techniques. The technique utilizes two stage procedures in order to identify the best capacitor location and sizes. In first phase, the loss sensitivity analysis is carried out using two sensitivity indices to obtain the most candidate capacitor locations along the distribution line. Further, the particle swarm optimization is adopted to find the optimal locations as well as its size. The objective function is formulated in such a way to minimize the power loss and capacitor cost. In this optimal placement study, different capacitor modules such as fixed, switched and its combinations are considered for analysis.
The backward/forward sweep algorithm is developed to perform the load flow calculations and the proposed method is tested on the IEEE 34 and 85 bus distribution systems. Moreover, the performance studies are also performed on a real distribution system of the east delta network to validate the feasibility. From comprehensive study, it has been inferred that the proposed procedure achieved significant savings in the system total cost. Further, in comparison with other methods, the proposed scheme is found to be suitable for big distribution systems and can considerably improves its performance.

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