Saman Hosseini-Hemati - Electrical Engineering Department, Engineering Faculty, Razi University, Kermanshah,
Shahram Karimi - Department of Electrical Engineering, Razi University, Kermanshah, Iran
Gholam Hossein Sheisi - Electrical Engineering Department, Engineering Faculty, Razi University, Kermanshah,

Secure and economical operation of distribution networks needs the management of reactive power resources. Optimal Reactive Power Dispatch (ORPD) optimally manages the reactive power scheduling of generators and distribution generations as well as the Reactive Power Compensation (RPC) devices. This paper investigates the effect of load models on the multi-objective ORPD problem in active distribution networks. Moreover, a modified Grey Wolf Optimizer (GWO), which is called in this paper as Civilized GWO (CGWO), is introduced to solve the ORPD problem. The proposed strategy including multi-objective function, various load models, DG’s reactive power, RPCs and the introduced CGWO, is tested on standard IEEE ۳۳- and ۶۹-bus distribution systems. The obtained results indicate the load models have significant impact on the cost function amount. Moreover, the performance of the proposed algorithm is evaluated using ten standard benchmark functions. The optimization results demonstrate the robustness of the introduced optimization algorithm and its ability in finding the better solutions compared to the Particle Swarm Optimization (PSO), Exchange Market Algorithm (EMA), and original GWO.

Civilized grey wolf optimizer, load modelling, Multi-objective optimization, optimal reactive power dispatch