A Novel Reduced Component Five-Level Hybrid NPP Inverter with Double Boosting Capability

Multilevel inverters (MLIs) are highly popular for their ability to generate high-quality output voltage with reduced total harmonic distortion (THD). The integration of boosting capability into MLIs further enhances their performance by allowing voltage boosting, which is essential for applications like renewable energy systems and electric vehicles. This paper demonstrates a novel way of enhancing the voltage gain of a hybrid H-bridge multilevel inverter. By incorporating only one semiconductor switch across each dc-link capacitor, and carefully controlling it, the voltage boosting capability of a five-level conventional hybrid H-bridge Neutral Point Piloted (NPP) inverter can be enhanced by 200%. The dc-link capacitor voltages are balanced automatically throughout cycles of charging and discharging by employing appropriate switching states. No additional sensors or control hardware are therefore required. To enhance voltage quality, switching signals are generated using a low frequency-based optimum nearest level modulation (NLM) technique. The system requires a total of 7 switches with a Total Standing Voltage (TSV) rating of 11V<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">in</inf>. A comprehensive simulation using MATLAB/Simulink is performed to validate the efficiency of the proposed topology. Moreover, outstanding dynamic performance is observed in a range of loading conditions.