Improved nearest level modulation for cascaded H-bridge converter

Characteristics of equivalent area method of the nearest level modulation (NLM) is analysed in detail and an improved NLM for ten or so cells of cascaded H-bridge (CHB) converter with a high modulation precision is proposed. The proposed algorithm can make the output voltage of the CHB converter better track the voltage modulation. Simulation results are presented to verify the validity of the proposed algorithm.