An efficient cascaded multilevel inverter suited for PV application

Two level inverters are common in PV applications. Due to large voltage swings in such a modulation, the switching losses are high reducing its conversion efficiency. Multilevel inverters employ smaller voltage steps and are preferred over 2-level modulation to obtain a higher dc to ac efficiency. The paper presents a novel multilevel inverter where the modulation strategy has provided “best possible performance” with an acceptable advantage in its implementation. Based on this strategy, a 1KW inverter was built and tested to evaluate its efficiency. The efficiency has been found to be in 99 percent range. For comparison, a commercial unit was tested for its efficiency and found to have a lower performance than the proposed multilevel inverter.