2. Kirchhoff’s voltage law also shows that only one diode in the bottom half of
the bridge may conduct at one time (D2, D4, or D6). The diode that is conducting will have its cathode connected to the phase voltage that is lowest at that instant.
3. As a consequence of items 1 and 2 above, D1and D4 cannot conduct at the same time. Similarly, D3 and D6
cannot conduct simultaneously, nor can D5and D2.
4. The output voltage across the load is one of the line-to-line voltages of the source. For example, when D1
and D2 are on, the output voltage is vac. Furthermore, the diodes that are on are determined by which line-to-line
voltage is the highest at that instant. For example, when vac is the highest line-to-line voltage, the output is v ac
.5. There are six combinations of line-to-line voltages (three phases taken two at a time). Considering one period of the source to be 360, a transition of the highest line-to-line voltage must take place every 360/6 60. Because
of the six transitions that occur for each period of the source voltage, the circuit is called a six-pulse rectifier.