Retificador Unidirecional Multinível com Regulação Automática das Tensões

Abstract

Multilevel rectifiers allow improving the system performance by reducing the harmonic content of synthesized voltages, which leads to minimizing the size and weight of the grid interface filters. Alternatively, the use of unidirectional PWM rectifiers is particularly interesting in situations where there is nonregenerative operation, since it is possible to operate with fewer active switches. This work proposes a unidirectional five-level rectifier which reduces the number of components needed and allows the automatic regulation of floating capacitors voltages, without employing complex control techniques with sensors and/or additional circuits. In addition, the proposed rectifier requires devices with lower reverse voltages and, consequently, the number of components in series can be minimized. Simulation results demonstrate the validity of the proposal.