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The copper rotor induction motor (CURIM) was recently introduced because it has lower rotor fusion losses than the aluminum rotor (ALRIM). Furthermore, with CURIM, it is easier to reach IE4 and IE5 efficiency levels. The CURIM is advantageous for compact motors, escalators, and electric vehicle applications. However, CURIMs present slip, power factor, temperature increase, and torque decrease problems that must be analyzed. This study compared the economic feasibility of using CURIM with ALRIM by applying discount techniques. A case study was carried out in a sugar company with a cyclical operation, where 5.5 kW motors will be installed in the intermediate conductors of the mill's feeders. The facility works three shifts between 3 and 6 months. The cost increase (ΔCI) of CURIM over ALRIM was between 1.1 and 1.5 times. With 3,600 h/year and 4,000 h/year of operation, the ΔCI greater than 10%, it was found that the payback is more than four years, and the net present value (NPV) grows linearly. [ABSTRACT FROM AUTHOR]

This paper aims to present a simulation model for the analysis of the operational characteristics of electric motors (EMs). The model was developed on the Simulink platform of the MATLAB program and allows analysis in supply conditions with harmonics and voltage unbalance. The contribution of the model is that it considers the mechanical losses and provides for the study of the effect of each component of the electrical sequence of the harmonics and the voltage unbalance on the electromechanical characteristics of the EM. The model developed was tested in a 37.3 kW EM, operating under four power supply conditions: balanced sinusoidal voltages, balanced non-sinusoidal voltages (i.e., harmonics), unbalanced sinusoidal voltages, and non-sinusoidal unbalanced voltages. The results showed that under the conditions of harmonics and unbalance, the efficiency was reduced by 2%, respectively and that with the combined effects, the efficiency decreased by 4%. The results made it possible to quantify, from the current, voltage, and electrical power values of each sequence, the adverse effects caused by voltage unbalance and harmonics. [ABSTRACT FROM AUTHOR]

In this paper was applied a method of energy planning, compatible with ISO 50001 standard, in an industrial laundry. In the analysis, three input variables were considered: level of production, technical condition of the system and operating regime. The past, present and future of fuel oil consumption in the steam generation and use was examined, establishing the causes of deterioration of consumption indicator. A study of load and capacity in the system identified potential savings through improved operating regime. A new regime for the operation of boilers was proposed and implemented, saving 16% of fuel. With the results of these measurements, the baseline was developed and goals are established. [ABSTRACT FROM AUTHOR]