"DCMLI has two advantages over conventional H-bridge inverter; the higher voltage capability and a reduced harmonic content".
eg see here for one example of that claim.
What does the above statement mean, I am failing to understand it.
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2\$\begingroup\$ Can you edit the question to explain the acronym and give a reference for the quote? \$\endgroup\$– TransistorCommented Sep 4, 2022 at 5:24
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\$\begingroup\$ You should cite the paper where that comment appeared- a number of papers are using that exact phrasing. eg here is one. The statement seems self evident - the real question is to understand why these advantages exist. The papr I cite claims an even better method. \$\endgroup\$– Russell McMahon ♦Commented Sep 8, 2022 at 1:25
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By DCMLI, I'm assuming that you mean a diode-clamped multilevel inverter. Multilevel inverters have a higher voltage capability in that the blocking voltage of the diodes and IGBTs of the inverter is reduced. In a standard 2-Level inverter (like H-bridge), the devices have to block the full DC-bus voltage; in a 3-Level inverter, the devices have to block half the DC-bus voltage and so on. So if you have 1200V rated IGBTs and diodes, you can theoretically use a 1200V DC-bus for an H-Bridge inverter. But with a 3-Level inverter, you can theoretically go up to 2400V. (But in reality, one would leave a safety margin).
As for reduced harmonic content, the addition of levels in the output of the inverter reduces the peak-to-peak voltage swing across you filter (Usually LCL), thereby reducing the current ripple and hence the harmonic content in it.
answered Sep 4, 2022 at 5:34