A high boost switched capacitor multilevel inverter with reduced components

ABSTRACT

Switched capacitor multilevel inverters (SCMLIs) became a popular DC-to-AC converter due to their unique features like self-capacitor voltage balancing and self-output voltage boosting abilities over conventional multilevel inverters in recent years. However, recently developed SCMLIs suffer from higher component counts, lower voltage boosting factors, higher total standing voltage, and the requirement of isolated DC sources for generating high-quality output voltage level waveform. These drawbacks make the inverter costly, complex, and bulky. To address these drawbacks of SCMLIs, a novel SCMLI is proposed in this paper. The proposed SCMLI can realise 17 output voltage levels with a higher boosting factor. In addition, the proposed SCMLI uses lower switches, driver circuits, capacitors, and diodes than similar SCMLIs. The proposed SCMLI also offers a cheaper cost function per output voltage level per boosting factor compared to others. A thorough description of the proposed inverter’s operating principle, voltage stress analysis, and capacitor selection procedure have been discussed. The proposed inverter’s cascaded form has been constructed and analysed for various DC source configurations. An extensive simulation study of 17-level SCMLI in MATLAB/Simulink platform and an experimental investigation on a 17-level laboratory prototype validate the proposed SCMLI’s merits and effectiveness.

KEYWORDS:

• Multilevel inverter
• switched capacitor
• total standing voltage
• voltage balance
• voltage boosting factor

Disclosure statement

No potential conflict of interest was reported by the author(s).