Associação de filtros ativos de potência paralelos em sistemas a três e quatro fios.

Abstract

Parallel active power filter (APF) is the solution more employed to improve the power system quality. Harmonics of the load current emitted by nonlinear loads are compensated by those lters. In this work are studied parallel association of APFs with three and four wires, in which are proposed two control philosophies for compensation of those harmonics. The rst strategy requires the power ow division equally between both lters, while the second established the division of compensation, where one lter compensate only the reactive and the other one compensate the harmonics components. For each topology studied will be addressed the following aspect: (i) modeling dynamics of the con guration; (ii) PWM strategy and (iii) control approach. A comparative study will be done in terms of harmonic distortions of the grid and power converter losses, as well; the conventional and the studied systems are employed in this comparison. The topologies composed of two APFs can reduce: the distortion of the grid, the high frequency losses in the dc-link, and the losses in semiconductor (IGBTs) devices, all compared to the conventional topology under the same conditions. The con gurations are validated by presenting the results of simulation and experimental.