Design and Implementation of a High-gain Switched-capacitor Step-up Multi-level Inverter with Reduced Components Count

Emergence of compact design power converters for applications such as photovoltaic system, active power filter, and high-frequency AC system has introduced multi-level inverters (MLIs). In the last decade, rigorous research has been carried out to transform multi-input MLIs to single-input step-up type that will be extremely beneficial in different applications. The proposed MLI in this work is a reduced components based switched-capacitor MLI. It consists of one input source and using the capacitor voltage, it can produce a four-time step-up output. One of the capacitors is charged to magnitude the input voltage and the other two capacitors are charged to two-time the input voltage magnitude. The charging of all the capacitors is executed by utilizing them in series-parallel combination with the switching operation. By maintaining charging-discharging effectively within each cycle, the voltages are naturally balanced. A thorough comparison is carried to justify the new development in terms of reduction in number of components and voltage stress. The power loss is estimated in the proposed circuit in detail. Extensive analysis is carried out to verify the operational ability and results are provided under different scenarios such as change in modulation index, load, and supply side variations.