WEG MVW3000 A0040 V023, User Manual

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MVW3000 | 3-3
3
MVW3000 | 3-3
Product Characteristics
R
S
T
Figure 3.2: Input transformer of the 18-cell MVW3000 (Frame B6)
Physically, the cells that form phases U, V and W are connected to the main transformer according to Figure 3.3
on page 3-3 .
U phase cells
V phase cells
W phase cells
Figure 3.3: Cell connection area of each phase
The transformer has its own panel, being thus totally integrated to the MVW3000. For more details on the panels,
refer to
Chapter 4 TECHNICAL DATA on page 4-1 , Figure 4.3 on page 4-3 , Table 4.2 on page 4-3 to Table
4.8 on page 4-4 .
3.2 POWER CELLS
The power cells used on the arms of the MVW3000 are single-phase low voltage inverters (output voltage of
690 V
rms
), in a topology known as H bridge or full bridge. A basic diagram of the rms power cell circuit can be seen
in Figure 3.4 on page 3-4 . Each cell has the feeding of one own secondary winding (three-phase) of the main
transformer, which ensures the converter medium voltage insulation.
The three-phase voltages of the input of the modules are then rectified by a Graetz bridge using non-controlled
semiconductor devices (diodes), forming one own DC link (direct current) with the addition of the capacitors to
the cell (represented by symbol C1). They can be electrolytic or plastic film capacitors, depending on the model
of the used cell.