Comparação de desempenhos de um Inversor Convencional e o de um Inversor Multinível na Filtragem Ativa Monofásica

This paper presents a comparative study between a Shunt Active Power Filter (SAPF) with a Conventional Inverter and with a 5-Level Neutral Point Clamped (NPC) Inverter based on MATLAB simulations. By comparing both kinds of equipment it is possible to acknowledge the main advantage of including some extra IGBTs, and the proper balance control of the Capacitor Voltages. The SAPF control is based on the Instantaneous Power Theory (P-Q Theory) and has as the main objective to calculate the reference current, responsible for the harmonic compensation, that will be generated by a single-phase inverter in series with an Inductor. As it was considered the higher harmonic distortion for the voltage source, according to the PRODIST norm of ANEEL, and the IEEE Std 519, a Phase-Locked Loop (PLL) was appropriatelly designed in order to obtain a perfect sinusoidal reference to be used with the SAPF control. Additionally, different switching strategies were considered for both type of inverters and a particular one is proposed for the single-phase NPC five-level inverter in order to have equal DC link capacitor voltages. Finally, after different simulations, the principal conclusions of this research are shown.