1. Zero-Voltage or Zero-Current Switchings
Chapter 9
Zero-Voltage or Zero-Current Switchings
converters for soft switching
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by John Wiley & Sons, Inc.
Chapter 9 Resonant Converters

2. Chapter 9 Resonant Converters
One Inverter Leg
The output current can be positive or negative
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by John Wiley & Sons, Inc.
Chapter 9 Resonant Converters

3. Hard Switching Waveforms
The output current can be positive or negative
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by John Wiley & Sons, Inc.
Chapter 9 Resonant Converters

4. Turn-on and Turn-off Snubbers
Turn-off snubbers are used
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by John Wiley & Sons, Inc.
Chapter 9 Resonant Converters

5. Switching Trajectories
Comparison of Hard versus soft switching
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by John Wiley & Sons, Inc.
Chapter 9 Resonant Converters

6. Undamped Series-Resonant Circuit
The waveforms shown include initial conditions
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by John Wiley & Sons, Inc.
Chapter 9 Resonant Converters

7. Series-Resonant Circuit with Capacitor-Parallel Load
The waveforms shown include initial conditions
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by John Wiley & Sons, Inc.
Chapter 9 Resonant Converters

8. Impedance of a Series-Resonant Circuit
The impedance is capacitive below the resonance frequency
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by John Wiley & Sons, Inc.
Chapter 9 Resonant Converters

9. Undamped Parallel-Resonant Circuit
Excited by a current source
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by John Wiley & Sons, Inc.
Chapter 9 Resonant Converters

10. Impedance of a Parallel-Resonant Circuit
The impedance is inductive at below the resonant frequency
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by John Wiley & Sons, Inc.
Chapter 9 Resonant Converters

11. Series Load Resonant (SLR) Converter
The transformer is ignored in this equivalent circuit
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by John Wiley & Sons, Inc.
Chapter 9 Resonant Converters

12. SLR Converter Waveforms
The operating frequency is below one-half the resonance frequency
Copyright © 2003
by John Wiley & Sons, Inc.
Chapter 9 Resonant Converters

13. SLR Converter Waveforms
The operating frequency is in between one-half the resonance frequency and the resonance frequency
Copyright © 2003
by John Wiley & Sons, Inc.
Chapter 9 Resonant Converters

14. SLR Converter Waveforms
The operating frequency is above the resonance frequency
Copyright © 2003
by John Wiley & Sons, Inc.
Chapter 9 Resonant Converters

15. Lossless Snubbers in SLR Converters
The operating frequency is above the resonance frequency
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by John Wiley & Sons, Inc.
Chapter 9 Resonant Converters

16. SLR Converter Characteristics
Output Current as a function of operating frequency for various values of the output voltage
Copyright © 2003
by John Wiley & Sons, Inc.
Chapter 9 Resonant Converters

17. Chapter 9 Resonant Converters
SLR Converter Control
The operating frequency is varied to regulate the output voltage
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by John Wiley & Sons, Inc.
Chapter 9 Resonant Converters

18. Parallel Load Resonant (PLR) Converter
The transformer is ignored in this equivalent circuit
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by John Wiley & Sons, Inc.
Chapter 9 Resonant Converters

19. PLR Converter Waveforms
The current is in a discontinuous conduction mode
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by John Wiley & Sons, Inc.
Chapter 9 Resonant Converters

20. PLR Converter Waveforms
The operating frequency is below the resonance frequency
Copyright © 2003
by John Wiley & Sons, Inc.
Chapter 9 Resonant Converters

21. PLR Converter Waveforms
The operating frequency is above the resonance frequency
Copyright © 2003
by John Wiley & Sons, Inc.
Chapter 9 Resonant Converters

22. PLR Converter Characteristics
Output voltage as a function of operating frequency for various values of the output current
Copyright © 2003
by John Wiley & Sons, Inc.
Chapter 9 Resonant Converters

23. Hybrid-Resonant DC-DC Converter
Combination of series and parallel resonance
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by John Wiley & Sons, Inc.
Chapter 9 Resonant Converters

24. Parallel-Resonant Current-Source Converter
Basic circuit to illustrate the operating principle at the fundamental frequency
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by John Wiley & Sons, Inc.
Chapter 9 Resonant Converters

25. Parallel-Resonant Current-Source Converter
Using thyristors; for induction heating
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by John Wiley & Sons, Inc.
Chapter 9 Resonant Converters

26. Chapter 9 Resonant Converters
Class-E Converters
Optimum mode
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by John Wiley & Sons, Inc.
Chapter 9 Resonant Converters

27. Chapter 9 Resonant Converters
Class-E Converters
Non-Optimum mode
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by John Wiley & Sons, Inc.
Chapter 9 Resonant Converters

28. Resonant Switch Converters
Classifications
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by John Wiley & Sons, Inc.
Chapter 9 Resonant Converters

29. ZCS Resonant-Switch Converter
One possible implementation
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by John Wiley & Sons, Inc.
Chapter 9 Resonant Converters

30. ZCS Resonant-Switch Converter
Waveforms; voltage is regulated by varying the switching frequency
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by John Wiley & Sons, Inc.
Chapter 9 Resonant Converters

31. ZCS Resonant-Switch Converter
A practical circuit
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by John Wiley & Sons, Inc.
Chapter 9 Resonant Converters

32. ZVS Resonant-Switch Converter
Serious limitations
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by John Wiley & Sons, Inc.
Chapter 9 Resonant Converters

33. ZVS Resonant-Switch Converter
Waveforms
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by John Wiley & Sons, Inc.
Chapter 9 Resonant Converters

34. MOSFET Internal Capacitances
These capacitances affect the MOSFET switching
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by John Wiley & Sons, Inc.
Chapter 9 Resonant Converters

35. ZVS-CV DC-DC Converter
The inductor current must reverse direction during each switching cycle
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by John Wiley & Sons, Inc.
Chapter 9 Resonant Converters

36. ZVS-CV DC-DC Converter
One transition is shown
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by John Wiley & Sons, Inc.
Chapter 9 Resonant Converters

37. ZVS-CV Principle Applied to DC-AC Inverters
Very large ripple in the output current
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by John Wiley & Sons, Inc.
Chapter 9 Resonant Converters

38. Three-Phase ZVS-CV DC-AC Inverter
Very large ripple in the output current
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by John Wiley & Sons, Inc.
Chapter 9 Resonant Converters

39. Output Regulation by Voltage Control
Each pole operates at nearly 50% duty-ratio
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by John Wiley & Sons, Inc.
Chapter 9 Resonant Converters

40. ZVS-CV with Voltage Cancellation
Commonly used
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by John Wiley & Sons, Inc.
Chapter 9 Resonant Converters

41. Resonant DC-Link Inverter
The dc-link voltage is made to oscillate
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by John Wiley & Sons, Inc.
Chapter 9 Resonant Converters

42. Three-Phase Resonant DC-Link Inverter
Modifications have been proposed
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by John Wiley & Sons, Inc.
Chapter 9 Resonant Converters

43. High-Frequency-Link Inverter
Basic principle for selecting integral half-cycles of the high-frequency ac input
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by John Wiley & Sons, Inc.
Chapter 9 Resonant Converters

44. High-Frequency-Link Inverter
Low-frequency ac output is synthesized by selecting integral half-cycles of the high-frequency ac input
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by John Wiley & Sons, Inc.
Chapter 9 Resonant Converters

45. High-Frequency-Link Inverter
Shows how to implement such an inverter
Copyright © 2003
by John Wiley & Sons, Inc.
Chapter 9 Resonant Converters