Christoph Haederli - Les thèses en ligne de l'INP - Institut National ...
Christoph Haederli - Les thèses en ligne de l'INP - Institut National ...
Christoph Haederli - Les thèses en ligne de l'INP - Institut National ...
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40 ML Converter Topologies<br />
1<br />
0.75<br />
0.5<br />
0.25<br />
Carrier 1<br />
Carrier 2<br />
Carrier 3<br />
Carrier 4<br />
Refer<strong>en</strong>ce 1<br />
Refer<strong>en</strong>ce 2<br />
Refer<strong>en</strong>ce 3<br />
Refer<strong>en</strong>ce 4<br />
Refer<strong>en</strong>ce 5<br />
0<br />
0 0.25 0.5 0.75 1<br />
Figure 36, Carrier waveform, sample refer<strong>en</strong>ce inputs and resulting flying capacitor application<br />
times<br />
Flying capacitor<br />
application time<br />
ratio (k 2)<br />
1<br />
1/M<br />
0<br />
0<br />
1/M (M-1)/M M<br />
Refer<strong>en</strong>ce<br />
Figure 37, flying capacitor application time<br />
Figure 37 indicates that there is a maximum k 2 of 1/M, M indicating the number of cells that<br />
can be operated interleaved. This can correspond with the number of cells within a giv<strong>en</strong> MC<br />
converter, or it can be a higher number based on series connected MC’s or a combination of MC<br />
and FS cells. This number M does not necessarily correspond with N for all topologies. N is the<br />
ratio of input supply voltage of the converter over one output voltage level (or lowest capacitor<br />
voltage), whereas M can refer to only a portion of the whole converter. In the case of the MC<br />
converter N equals M; in the case of the SMC or the ANPC1 and ANPC2, N equals 2 times M.<br />
The switching frequ<strong>en</strong>cy may also vary <strong>de</strong>p<strong>en</strong>ding on topology and operating point. A factor k f_sw<br />
shall be <strong>de</strong>fined to express the actual switching frequ<strong>en</strong>cy in function of a base frequ<strong>en</strong>cy<br />
corresponding with a pure MC converter operation. Starting from Figure 37, the total flying<br />
capacitor <strong>en</strong>ergy of all consi<strong>de</strong>red topologies can be calculated.