Electric diagram conception of a new substation BH Centro 2- Belo Horizonte - Minas Gerais - Brazil

This paper presents the electric diagram conception of the new substation BH Centro 2, which will substitute the existent substation BH Centro 1, that currently supplies the central area of Belo Horizonte city. The BH Centro 1 substation is the biggest substation of Cemig Distribution Company, with regard to its transformation capacity (138-13.8 kV – 150 MVA). Operating since 1970, the substation has been showing maintenance problems associates to the difficulty of attainment of spare parts for some equipment and rise of the risk of failure due to its high period of operation. Thus, the construction of a new substation was defined. The conception of the BH Centro 2 substation faced some challenges, due limitations of space, special operational requirements because of medium voltage networks characteristics and short-circuits level limitation. Besides, we tried to avoid the utilization of special equipments, like high impedance transformers and high capacity reactors.