Nowadays, the most generated electrical energy is consumed by three-phase induction motors. Thus, in order to carry out preventive measurements and maintenances and eventually employing high-efficiency motors, the efficiency evaluation of induction motors is vital. In this paper, a novel and efficient method based on Improved Big Bang-Big Crunch (I-BB-BC) Algorithm is presented for efficiency estimation in the induction motors. In order to estimate the induction motor’s efficiency, the measured current, the power factor and the input power are applied to the proposed method and an appropriate objective function is presented. The main advantage of the proposed method is efficiency evaluation of induction motor without any intrusive test. Moreover, a new effective and improved version of BB-BC algorithm is introduced. The presented modifications can improve the accuracy and speed of the classic version of algorithm. In order to demonstrate the capabilities of the proposed method, a comparison with other traditional methods and intelligent optimization algorithms is performed.
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