Análise do desbalanço de tensão em sistemas de distribuição de energia elétrica trifásicos à dois fios

Abstract

The growing demand for higher levels of electrical power in rural areas is a reflection of the modernization of the countryside. This phenomenon has led energy concessionaires to invest in technologies that enable the repowering of existing medium voltage distribution systems, in addition to the implementation of new networks. The three-phase two-wire distribution system is a new economically viable alternative, capable of supplying three-phase demand at full power, using only two overhead wires and the ground as conductors. An inherit characteristic of this system is the presence of a voltage unbalance between the phases that supply the loads. This aspect of the system is due to the impedance difference between the overhead phases and the one transmitted by the ground. This work presents two scientific articles that address the quality of the energy supply in the proposed system, discussing parameters that allow its implementation in a viable way according to the norms, besides presenting different methodologies that aim to remedy the unbalance between the phases. The studies presented were developed in their entirety using the MATLAB/Simulink simulation software. The obtained results demonstrated a wide possibility of implementations within the acceptable patterns of voltage unbalance. In addition, it is presented a methodology capable of eliminating these unbalances with great efficiency in systems that do not conform to the norms.