DC to AC 3 phase modular multilevel conversion using Chireix outphasing method

摘要

This paper describes application of the Chireix outphasing method of the Linear Amplification using Non-Linear Components (LINC) to the design of DC to 3 Phase AC modular multilevel inverters with fully controlled amplitude and phase. Synthesizing sine voltages with low harmonic content while using power switches operating at fundamental line frequency keeps switching losses low and allows using of the highest power and the highest voltage rated but slow switching components. Stacking DC inputs of individual inverter modules in series fits requirements for HVDC line converter to AC 3 phase outputs with minimum output voltage waveform filtering. A unique capability of controlling output voltages from zero to maximum may be useful for such inherently unstable renewable sources of energy as wind and solar.