Abstract
Abstract In this paper several modulation techniques for a three-level neutral-point-clamped quasi impedance source inverter are proposed and discussed. Mathematical descriptions with simulation results are presented for each modulation technique. Their advantages and disadvantages are shown and guidelines for further improvement are provided.
Highlights
A three-level neutral-point-clamped (3L-NPC) inverter has a number of advantages, such as lower semiconductor voltage stress, lower required blocking voltage capability, decreased dv/dt, better harmonic performance, soft switching possibilities without additional components, higher switching frequency due to lower switching losses, and balanced neutralpoint voltage in comparison with the two-level voltage source inverter [1]
To obtain buck and boost performance the focus is turned onto a quasi-Z-source inverter
In modulation technique 2, the desired boost is reached because the shoot-through states are distributed with the constant width during the whole output voltage period and the qZ stage is working at a maximum frequency
Summary
A three-level neutral-point-clamped (3L-NPC) inverter has a number of advantages, such as lower semiconductor voltage stress, lower required blocking voltage capability, decreased dv/dt, better harmonic performance, soft switching possibilities without additional components, higher switching frequency due to lower switching losses, and balanced neutralpoint voltage in comparison with the two-level voltage source inverter [1]. The qZSI can boost the input voltage by introducing a special shoot-through switching state, which is the simultaneous conduction (cross conduction) of both switches of the same phase leg of the inverter. This switching state is forbidden for traditional voltage source inverters because it causes a short circuit of the DC-link capacitors. At the same time shoot-through switching state demands new approaches to modulation techniques in order to combine the boost factor, lower input current ripple and more capacitor voltage balance with the best possible output voltage quality. It can be used in distributed energy resources, such as photovoltaic plants, fuel cells, etc
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
