2. Advantages of Three-Phase Rectifiers over Single-Phase Rectifiers
Higher output voltage for given input voltage.
Lower amplitude ripples i.e., output voltage is smoother
Higher frequency ripples, simplifying filtering
(lower size of filter circuit parameters because of higher ripple frequency)
Higher overall efficiency 2

3. Three-Phase Half-Wave Rectifiers
Three-Pulse Rectifiers 3

4. Load voltage waveforms
Circuit Diagram
Load voltage waveforms 4

5. Current Waveforms 5

6. VD1 VD2 VD3 VAC VBC VCA VCB Period On diode Off diodes 030 ° D3
D1 & D2
VAC
VBC
30 º150º D1
D2 & D3
VCA
150º 270º D2
D3 & D1
VCB
270º390º 6

7. Voltage across diodes
VD1 7

8. VD2

9. VD3

10. With Inductive Load 10

11. THREE-PHASE FULL-WAVE BRIDGE RECTIFIERS
Six-Pulse Rectifiers

13. Equivalent circuits of six-pulse rectifier

15. Diode and Line current waveforms

20. With Inductive (RL) Load

21. TWELVE-PULSE RECTIFIERS

22. Circuit Diagram