New module integrated multilevel inverter for grid connection of photovoltaic plants

Abstract

This paper presents a new solar multilevel inver-ter,  based  on  the  cascaded-multilevel  converter.  The  main  idea  is  that  the  new  inverter  generates  a  so  called  “highly  pulsating  space  phasor”  instead  of  a  reference  voltage.  This  operation  mode  limits  the  distortions.  Additionally,  for  the  first  time  energy  redundancies  between  the  voltage  levels  can  be  used,  instead  of  the  so  far  known  voltage  redundancies.  As  a  result,  the  problem  of  unbalanced  voltage  sources  can  be  avoided,  a  complex  control  is  not  necessary  anymore  and  the  MPP  track-ing of solar multilevel inverters can be improved considerably.