A single‐source nine‐level inverter with quadratic boost ability for renewable energy applications

Abstract

A nine‐level inverter with quadratic boost ability is proposed in this paper. The presented topology produces quadruple boosted output voltage by utilizing 10 switches, one diode, two capacitors, and a single dc source. In the proposed topology a back‐end H‐bridge is not required to produce negative voltage levels, which in turn reduces the voltage stress across the switches to the maximum of twice the input voltage. The two switched capacitors (SC) are charged to the dc source voltage rating and twice the voltage rating of the dc source, respectively, to produce quadruple voltage boosting. The high‐voltage boosting capability makes it suitable for the integration of renewable energy sources to the grid. Nearest level control (NLC)‐based modulation technique is applied to produce gate driver signals for the inverter circuit. The proposed topology is compared with the recently published topologies in terms of used components such as switches, diodes, sources, and capacitors are made so as to show the advantages of the presented reduced component count topology. Finally, simulation and hardware results are obtained under certain loading conditions to validate the operability of the proposed topology. The total harmonic distortion (THD) of the proposed topology at the unity modulation index is 8.2%.

A single‐source switched‐capacitor based 13‐level sextuple boost inverter with reduced component count and low THD

“…The on‐state resistances and the forward voltage drop across the devices in the load current path are the main causes of conduction loss [32–36]. Maximum load current flows at maximum levels, resulting in high voltage stress across the switches and maximum conduction loss.…”

“…Also, N on and N off are low for the proposed topology as S 9 and S 10 are either switched off or on in a complete half cycle, and other switches (S 5 , S 6 , S 7 , S 8 ) also have less number of switching, resulting in reduced switching loss. The on-state resistances and the forward voltage drop across the devices in the load current path are the main causes of conduction loss [32][33][34][35][36]. Maximum load current flows at maximum levels, resulting in high voltage stress across the switches and maximum conduction loss.…”

A 7L and 11L High Step-Up SCMLI Topology With Reduced Component Voltage Stress

“…However, they need to have the dc-link voltage equal to the input voltage making the system to add front end boost converter for grid connected applications. Another 9L topology using three switched capacitor is discussed in [9], capable of quadratic voltage gain and inherent voltage balancing. However, it requires a tiny inductor to suppress the inrush current.…”

Grid‐connected operation and control of single‐phase asymmetrical multilevel inverter for distributed power generation

“…H‐bridge circuit is needed to produce negative levels in the output voltage; hence the voltage stress across the switches is more, which in turn increases the total standing voltage. A quadruple boosted nine‐level inverter utilizing ten switches is presented in [11]. It requires lesser voltage dc source for grid integration.…”