A CUCKOO SEARCH BASED CO-ORDINATION OF DISTRIBUTED GENERATION UNITS AND SHUNT CAPACITOR BANK IN RADIAL DISTRIBUTION NETWORKS

ABSTRACT
 
This research work presents the Application of Cuckoo Search Algorithm for the simultaneous placement of distributed generation units and shunt capacitor banks in radial distribution networks. The approaches used in most literatures for determining the optimal allocation of DG units and Capacitor banks did not consider the simultaneous placement of multiple combinations of DG units and capacitor banks in order to obtain the best combination of optimal sizes and installed an appropriate location for optimal network performance. The Cuckoo Search Algorithm was applied to determine the optimal location and sizes of Micro-DG units and Shunt Capacitor Banks with an objective of minimizing the total active and reactive power loss and maximizing voltage profile improvement and voltage stability of distribution networks. The DGs units and Capacitor banks where separately and simultaneously applied on standard IEEE 33 and 69 test bus systems and on 50 bus Canteen Feeder in Zaria distribution network. The result obtained from the simultaneous allocation was validated by comparing with that obtained from the separate allocation of Distributed Generators and Capacitor Banks. For the 33 bus test system, the Cuckoo search algorithm found the optimal sizes and locations of the best simultaneous combination of the DG units and capacitor bank allocated to be 515.69 kW at bus 25, 214.01 kW at bus 32 and 572.27 kVAr at bus 30 with 63.29% and 59.38% reduction in active and reactive power loss, 6.32% Improvement in average voltage profile and 7.89% in overall VSI, as compared to 31.65% and 31.25% active and reactive power loss reduction, 5.11% improvement in average voltage profile and 6.13% in overall VSI for separate DG placements, and 53.16% and 53.13% power loss reductions, 3,95% improvement in average voltage profile and 3.85% improvement in overall VSI for separate capacitor bank placement when compared to the base case result. For the standard IEEE 69 test bus system the optimal sizes and locations of the best combinations of DG units and CBs that were simultaneously allocated were found to be 239.83 kW at bus 53, 885.58 kW at bus 50 and 1408.79 kVAr at bus 50 with 74.29% and 79.17% reduction in active and reactive power loss, 2.34% Improvement in average voltage profile and 3.79% in overall VSI as compared to 51.43% and 54.17% active and reactive power loss reduction, 2.02% improvement in average voltage profile and 2.69% in overall VSI for the separate DG placements and 28.57% and 31.25% active and reactive power loss reductions, 1.65% improvement in average voltage profile for separate capacitor banks placement when compared to base case results. Finally for the 50– bus Canteen Feeder in Zaria distribution network, the optimal sizes and locations of the best combinations of DG units and capacitor banks simultaneously allocated was 247.19 kW at bus 23, 137.82 kVAr at bus 25 and 131.78 kW at bus 25 with 17.77% and 17.76% reduction in active and reactive power loss, 0.47% improvement in average voltage profile and 0.32% improvement in overall VSI as compared to 15.70% and 15.79% active and reactive power loss reductions,0.45% improvement in average voltage profile and 0.30% improvement in overall VSI for the separate DG placements, 9.92% and 9.87% active and reactive power loss reductions, 0.38% improvement in average voltage profile and 0.28% improvement in overall VSI for separate capacitor banks placements when compared to the base case results. From results comparison, it is evident that the simultaneous placement of DGs and Capacitor banks using the cuckoo search algorithm gave a better performance to the separate placement of the DG units and capacitor banks.