Advanced control of grid--connected multilevel power electronic rectifiers

摘要: Multilevel power electronic converters have been gaining attention due to their ability supply high amounts of and handle voltage levels. In this dissertation, grid connected AC−DC rectifier application is investigated with different topologies control scheme. At first, neutral point clamped (NPC) employed transfer from the load. The NPC has two capacitors in order build multilevel output voltage. However, it causes unbalancing problem. Therefore, new method proposed regulate each capacitor at same level. Experimental results show that effective balance voltages can improve total harmonic distortion (THD) current as a result. Furthermore, 7 levels be achieved by using hybrid which consists an cascaded H-bridges (CHB). Because 8 are completely discharged large inrush currents might cause hazards. paper develops pre-charge routine for building up steady state operation unity factor (PFC) load achieved. Finally, multiple reference frame theory (MRF) used THD when distorted source. After calculating 5th real time, will compensated feedback loop. validity improving currents.