Transformerless Partial Voltage Converters for PV-BESS Plants

The concept of partial power converter is promising since it might bring significant cost, weight, volume and loss reduction. However, in most cases partial power converters include a transformer to redirect power from one part of the circuit to another. The transformer adds cost, weight, volume and losses and cancels most of the gains promised by the partiality concept. In this paper a Transformer-Less Partial Voltage Converter allowing the regulation of currents in a multistring system is described and analyzed, its main properties are explained and an example of application for PV or battery storage system is presented.