Transformerless Three Phase High Quality Multilevel Inverter Using a Common DC Source (KEY IJP************232)

• Dharavath Upender Naik , Bezzam Milka Ranjith

Abstract

This research proposes a transformerless high-resolution hybrid asymmetrical multilevel inverter. A mix of the Level Doubling Network (LDN), cascaded H-bridge (CHB), and neutral point clamped (NPC) multilevel inverter (MLI) is the proposed topology. The proposed research intends to lower the inter array leakage current and dc-bus capacitor demand by merging all three of the main bridges dc buses using TNPC. The primary difficulty with this hybrid transformerless converter architecture is matching the correct LDN operation to the TNPC capacitors. One more low-rated non-isolated buck-boost converter and a closed-loop current control are utilized for the capacitor balancing of TNPC, which will ultimately assist in getting rid of a large, pricey transformer. With an extra converter that only has a rating of 7% to 8% of the transformer rating, it will assist to save both capital and operating costs. Compared to other asymmetrical MLI topologies with identical resolution at output voltage, this architecture provides higher power quality, reliability and efficiency with fewer components. Utilizing the MATLABSimulink model, simulation was carried out and outcomes closely resembled concept.