A DC-DC Converter-Based Single-Source Transformer-less Multilevel Inverter

Voltage Source Inverters (VSIs) are one of the most important power electronic converters in power industry. Generally, an inverter realizes a desired AC voltage with an arbitrary amplitude and frequency using a DC voltage source. The DC source can be a set of battery, an array of photovoltaic cells, fuel cells, and so on. In some applications such as photovoltaic systems, the voltage magnitude of the DC source needs to be boosted. In certain applications, e.g. the machine drives, a controller with a high bandwidth is required. In this regard, the slow output filters can be eliminated using a multilevel inverter. In this study, a comprehensive converter topology of a single-source boosting multilevel inverter is proposed to meet the above-mentioned requirements. Due to the above-mentioned features, the proposed inverter is referred to boosting multilevel voltage source inverter (BM-VSI). The suggested BM-VSI realizes a seven-level phase-to-phase staircase ac voltage using two DC-DC Cuk converters and only one DC source. The developed output voltage in the proposed BM-VSI is three times of the conventional voltage source inverter. The performance of the proposed topology is evaluated using a laboratory-scaled prototype.