Review on A Single Phase Grid Connected Five-Level Converter for Renewable Distribution System with Reactive Power Control

Abstract

Single phase converters are the popular choice in low-power grid connected systems. However, these converters invariably use a power transformer on the output side, which increases the system losses, cost and size. This paper discusses a five-level single phase converter topology that does not require a transformer on the output side, thereby removing the disadvantages associated with it. The converter architecture is based on a full bridge topology, with an addition of two more power switches and two diodes. The diodes are connected to the midpoint of the dc link. Since the discharging of the two capacitors is responsible for the addition of the added levels, the balancing of the midpoint voltage of the capacitors has been considered. Further, the control of the amount of reactive power fed into the grid by the converter is also considered in the control scheme. Simulation results will be used to show the effectiveness of the proposed solution.