Journal of Electrical and Electronic Engineering 2014; 2(2): 41-46 Published online June 30, 2014 (http://www.sciencepublishinggroup.com/j/jeee) doi: 10.11648/j.jeee.20140202.12 Aspects regarding operation characteristics of brushless direct current motors Ion Vlad, Sorin Enache, Monica Adela Enache University of Craiova, Faculty of Electrical Engineering, Craiova, Romania Email address: ivlad@em.ucv.ro (I. Vlad), senache@em.ucv.ro (S. Enache), menache@em.ucv.ro (M. A. Enache) To cite this article: Ion Vlad, Sorin Enache, Monica Adela Enache. Aspects Regarding Operation Characteristics of Brush-less Direct Current Motors. Journal of Electrical and Electronic Engineering. Vol. 2, No. 2, 2014, pp. 41-46. doi: 10.11648/j.jeee.20140202.12 Abstract: The researches regarding optimization in the area of electrical machines, include with priority the problem of the energy efficiency, by increasing the efficiency and the power factor. The objectives followed in this paper are the analysis of the operation characteristics, the fabrication and exploitation cost for brushless direct current motors rated at very low power. The utilization of permanent magnets having high specific energy in the construction of these motors influenced the machine performances, the cost and exploitation price. The research carried out aims at reducing the electrical energy consumption in exploitation by optimally dimensioning the permanent magnets. The last part of the paper compares two motors (brushless direct current motor and synchronous motor), both of them having permanent magnets, the same rated data, the same electromagnetic stresses and the same main constructive dimensions. It results that, using the brushless direct current motor instead of the synchronous one, the consumption of active electrical energy is reduced with 11.8%, and the machine weight is reduced with 12.7%. Keywords: Brushless Direct Current Motors, Modelling, Simulation, Characteristics 1. Introduction Further on there is presented an analysis carried out for a brushless direct current motor, regarding its design, technical and economic parameter and its operation characteristics. The judicious choice of the type of electrical motor has a strong influence upon the gauge and the weight of the equipment, by the command scheme and the dynamic features of the drive. Brushless direct current motors are widely used for electrical drive systems [2]-[4]. Among their benefits, we can mention high efficiency, stable and reliable operation [7], [9], [25].. The analysis presented further on is useful to maximize the useful magnetic flux, which might lead to an efficient utilization of the active materials of the motor [12]. The present technique is conditioned by the utilization of permanent magnets [3], [5]-[6], [11], [13], which are present in the construction of several equipments. The most numerous applications are in the area of energy conversion, the permanent magnets being widely used in the construction of electrical machines. The development of the fabrication technology for rare earths based permanent magnets has led to the increase of the production and to the decrease of their cost price. Their utilization in excitation systems has made possible to obtain some motors having a very high ratio torque developed/unit of volume, better performances, by miniaturization, some compact and reliable equipments. The lack of the excitation winding makes brushless direct current motors to have a better efficiency and a lower volume in comparison with the classical ones [18]-[19], [24]. For a certain air-gap magnetic induction, the volume of an inductor having permanent magnets is smaller than in the case of an inductor having electromagnetic inductor. In this study [16]-[17], we have approached the permanent magnet direct current motors rated at very low power, used for DVD, tape recorders, office equipments, portable devices for sound recording and reproduction etc. For design and exploitation it is necessary to know some exact mathematical models, in order to obtain good performances in operation. On the basis of the analytical model, by numerical modeling [1], [8], [10], the design has been conceived then the characteristics required in exploitation have been computed and plotted. In these circumstances, the theme approached in this research is a subject of large interest for engineering area.