Technical and Economical Assessment of the Efficiency Improvement of Induction Motors after Rewinding

Increasing the efficiency of motors has a significant effect on their energy saving consumption. By calculating the annual energy consumption of a motor, the effect of increasing the efficiency on energy savings can be estimated. One of the most effective and inexpensive ways to increase the energy efficiency of motors is rewinding or redesigning the stator winding. Cost savings and reducing energy consumption by rewinding motors can attract investors' attention. In this paper, a single-phase induction motor with 0.75 horsepower, Rewinded for three-phase operation, and electromagnetic analysis of finite element method was performed using Flux software and its operation characteristics have been analysed. Economic analysis including operating costs, payback period and annual energy savings are also calculated. According to the results, the efficiency of the three-phase rewinded motor compared with the single-phase induction motor, increased about 12.5%, and the payback period based on 13 cents per kilowatt-hour was about one years. Based on the comparison, replacing a single-phase induction moto with the three-phase rewinded motor by standard efficiency (IE1) is economical than replacing motor in this class of efficiency and cost saving in full load achieve about 61$. For validation, the experimental results were compared with the simulation results and measurement error of about 6% was observed.