Multilevel converter circuit for generating a plurality of voltage levels

摘要

In some aspects, a direct current power source, formed of a series connection circuit of single power sources, which has three mutually different voltage levels including zero can be provided with first, second, third, and fourth arm pairs, each configured by connecting two arms formed of semiconductor switches in series, an alternating current switch configured by combining semiconductor switches. As such, a plurality of voltage levels can be to be selected from and output by an on and off control of these switch elements.

主权项

1. A multilevel converter circuit which generates a plurality of voltage levels from a direct current power source divided into two portions, including three terminals, and having three mutually different voltage levels including zero, and selects from and outputs the plurality of voltage levels, comprising:
first, second, third, and fourth arm pairs, each configured by connecting two arms formed of semiconductor switches directly in series; and a first alternating current switch configured by combining semiconductor switches, the multilevel converter circuit wherein respective outer side terminals of the first arm pair, second arm pair, and third arm pair are connected in series, in order from a first direct current terminal, between the first direct current terminal wherein the potential of the direct current power source is highest and a third direct current terminal wherein the potential is lowest, the outer side terminals of the fourth arm pair are connected between the midpoint terminal of the first arm pair and the midpoint terminal of the third arm pair, both ends of the first alternating current switch are connected between the midpoint terminal of the fourth arm pair and a second direct current terminal wherein the potential of the direct current power source is intermediate, both ends of each of a first capacitor and second capacitor are directly connected in parallel to both ends of each of the second arm pair and fourth arm pair respectively, the first capacitor having a value to provide a first voltage, the second capacitor having a value to provide a second voltage, the first and second voltages each being a predetermined proportion to the two portions of the direct current power source, and the midpoint terminal of the second arm pair is formed as an alternating current terminal.