A multilevel compensator with reduced number of switches used as auto-rectifies active filter for harmonics elimination

Active power filters are used to improve the energy quality of the electrical distribution networks by the harmonic elimination and correcting of the power factor. However, many conventional configurations of active filters are constituted by a significant number of semiconductors that generate a crowded installation with a complicated control, high cost price of his designs and power losses due to switching of semiconductors. For these reasons, the innovation of these configurations is required. This article, presents a proposed structure of multilevel active power filter auto-rectifies with a reduced number of switches. It is controlled by an easy flowchart permitting a functioning fast and efficient to eliminate the named problems of traditional structures. The use of this structure also reduces to half the number of DC bus capacities of its supply. Conventional systems such as seven levels inverter NPC-type require twelve power switches, six capacities of DC bus and diodes of neutral point clamped. The proposed model retained its ability to produce the same seven levels of voltage with only a small number of eight bipolar switches, three capacities of DC bus and none diode used for the neutral point clamped. The simulation results illustrate an important reduction in THD of current supply from 25.35% to 1.82%, that's less significant than the value conform to IEEE standards of 5% with a good compensation of reactive power.