1 / 26

Chapter 5 Diode Rectifiers

Chapter 5 Diode Rectifiers. Basic rectifier concepts Single-Phase diode bridge rectifiers Voltage-Doubler rectifiers. Diode Rectifier Block Diagram. Uncontrolled utility interface (ac to dc). A Simple Circuit ( R Load). Resistive load. A Simple Circuit ( R-L Load).

troy-jenkins
Download Presentation

Chapter 5 Diode Rectifiers

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Chapter 5 Diode Rectifiers • Basic rectifier concepts • Single-Phase diode bridge rectifiers • Voltage-Doubler rectifiers Chapter 5 Line-Frequency Diode Rectifiers

  2. Diode Rectifier Block Diagram • Uncontrolled utility interface (ac to dc) Chapter 5 Line-Frequency Diode Rectifiers

  3. A Simple Circuit (R Load) • Resistive load Chapter 5 Line-Frequency Diode Rectifiers

  4. A Simple Circuit (R-L Load) • Current continues to flows for a while even after the input voltage has gone negative Chapter 5 Line-Frequency Diode Rectifiers

  5. A Simple Circuit (R-L Load) Chapter 5 Line-Frequency Diode Rectifiers

  6. A Simple Circuit (Load has a dc back-emf) • Current begins to flow when the input voltage exceeds the dc back-emf • Current continues to flows for a while even after the input voltage has gone below the dc back-emf Chapter 5 Line-Frequency Diode Rectifiers

  7. Single-Phase Diode Rectifier Bridge • Large capacitor at the dc output for filtering and energy storage Chapter 5 Line-Frequency Diode Rectifiers

  8. Diode-Rectifier Bridge Analysis R load I load • Two simple (idealized) cases to begin with: (a) R load (b) current load Chapter 5 Line-Frequency Diode Rectifiers

  9. Waveforms with a purely resistive load at the output Chapter 5 Line-Frequency Diode Rectifiers

  10. Diode-Rectifier Bridge Input Current THD=48.43% DPF=1.0PF=DPF x Is1/Is=0.9 • Idealized case with a purely dc output current Chapter 5 Line-Frequency Diode Rectifiers

  11. Diode-Rectifier Analysis with AC-Side Inductance • Output current is assumed to be purely dc Chapter 5 Line-Frequency Diode Rectifiers

  12. Understanding Current Commutation • Assuming inductance to be zero Chapter 5 Line-Frequency Diode Rectifiers

  13. Understanding Current Commutation #2 • Assuming inductance to be zero Chapter 5 Line-Frequency Diode Rectifiers

  14. Understanding Current Commutation #3 • Assuming inductance to be zero Chapter 5 Line-Frequency Diode Rectifiers

  15. Understanding Current Commutation #4 • Inductance is included Chapter 5 Line-Frequency Diode Rectifiers

  16. Current Commutation Waveforms vd u vL Id is Chapter 5 Line-Frequency Diode Rectifiers

  17. Current Commutation Waveforms Chapter 5 Line-Frequency Diode Rectifiers

  18. Average voltage <Vd> When L=0 With finite L Reduction in average output voltage Chapter 5 Line-Frequency Diode Rectifiers

  19. Current Commutation in Full-Bridge Rectifier Chapter 5 Line-Frequency Diode Rectifiers

  20. Current Commutation in Full-Bridge Rectifier Chapter 5 Line-Frequency Diode Rectifiers

  21. Current Commutation Waveforms Chapter 5 Line-Frequency Diode Rectifiers

  22. Average voltage <Vd> When L=0 With finite L Reduction in average output voltage Chapter 5 Line-Frequency Diode Rectifiers

  23. Conclusions • Average output voltage drops with • increased current • increased frequency • Increased L • Load Regulation is a major consideration in most rectifier systems because • voltage changes with load (IL) Chapter 5 Line-Frequency Diode Rectifiers

  24. Diode-Rectifier with a Capacitor Filter • Power electronics load is represented by an equivalent load resistance Chapter 5 Line-Frequency Diode Rectifiers

  25. Diode-Bridge Rectifier: Waveforms • Analysis using PSpice Chapter 5 Line-Frequency Diode Rectifiers

  26. Voltage Doubler Rectifier input input • In 115-V position, one capacitor at-a-time is charged from the input. Chapter 5 Line-Frequency Diode Rectifiers

More Related