Analysis of the Topologies of Power Filters Applied in Distributed Generation Units - Review

Considering the current scenario of the advance of the use of renewable energy sources, mainly wind and solar photovoltaic, in the Brazilian energy matrix. At the same time, there is concern about the stability of the power system and its respective power quality (PQ), due to this type of generation of non-linear loads, such as current converters, which in turn cause distortion Of the current and voltage waveform. The generation of energy by renewable sources does not participate in the control of the voltage and frequency of the electrical system, and in the occurrence of disturbances that exceed the pre-established limits and that affect the system's PQ, are disconnected until the PQ is restored, to be Reconnected after normal operation returns. In order to standardize and quantify the electromagnetic disturbances of the QEE, as well as ensure the quality of the product and services, standards and procedures were designed to instruct from generators to energy consumers. In Brazil, the Electric Power Distribution Procedure in the National Electric System (PRODIST) - module 8. The disturbances of the PQ in the generating units, mainly wind and solar photovoltaic are caused by the harmonics of current, generated by the converters, causing the distortion in the waveform, which in turn, increases the losses in transformers and transmission lines, reduction of cable and equipment life, flicker. Among the possible techniques to minimize the effects of harmonics, the use of passive, active and hybrid filters stands out. However the applicability of each type of filter depends on each system where it will be applied according to the characteristics of the electrical system. Thus, in order to contribute to the advancement of the topic, it can be observed that the use of power filters has a good functionality in harmonic attenuation as well as economical solution. Therefore, this work presents a mapping of the main technologies and methodologies for the design of power filters that can be customized for the mitigation of harmonic disturbances and improvement of the power factor. Finally, it presents a comparative analysis between the topologies of power filters, followed by an alternative proposal of an automated filter for microgeneration of energy connected in low voltage.