Abstract

Purpose- This paper presents a new approach for the optimal design of protective current transformers (CTs). The proposed technique is applied to the design of typical CTs and results are compared. Design/methodology/approach- The aim of CT design is to make current measurements more accurate, particularly for the high fault currents that arise in short circuits, and more efficient in terms of both CT size and cost. The present work formulates these objectives as an optimization problem to be solved by particle swarm optimization (PSO).    Findings- Results of the simulation demonstrate the effectiveness of this technique in optimizing the CT design parameters. The designed CTs have smaller measurement errors compared to standard values and respond well to high fault currents. Manufacturing costs have also been reduced. Originality/value- In addition improved efficiency, the benefits of this method are in its treatment of CT design in terms of an equivalent circuit and design parameters. The proposed algorithm also extends the linear operation area of the CT and guarantees its good response to high fault currents that may occur in the power system.