Circuits and methods for controlling bidirectional CLLC converters
A bidirectional power converter includes a first switch circuit coupled to a second switch circuit via a transformer, wherein the first switch circuit is configured to transfer power to the second switch circuit during a charging mode, the second switch circuit is configured to transfer power to the first switch circuit during a discharging mode, and the first switch circuit is configured to operate in a half bridge configuration during a first portion of the charging mode.
1. A bidirectional power converter comprising:
a first switch circuit coupled to a second switch circuit via a transformer,
wherein the first switch circuit is configured to transfer power to the second switch circuit during a charging mode,
wherein the second switch circuit is configured to transfer power to the first switch circuit during a discharging mode,
wherein the first switch circuit is configured to operate in a half bridge configuration during a first portion of the charging mode, and in a full bridge synchronous rectifier configuration during a first portion of the discharging mode,
wherein the second switch circuit is configured to operate in a half bridge configuration during the first portion of the discharging mode, and
wherein a first switch of the first switch circuit is configured to be active during at least part of the first portion of the discharging mode.
2. The bidirectional power converter of claim 1 , wherein the second switch circuit is configured to operate as a full bridge synchronous rectifier during the first portion of the charging mode, and
wherein a switch of the second switch circuit is configured to be active during at least part of the first portion of the charging mode.
3. The bidirectional power converter of claim 1 , wherein the first switch and a second switch of the first switch circuit are configured to be simultaneously active during part of the first portion of the charging mode.
4. The bidirectional power converter of claim 3 , wherein the first switch is configured to transition from a deactivation state to an activation state at substantially the same time that the second switch is configured to transition from a deactivation state to an activation state during the first portion of the charging mode.
5. The bidirectional power converter of claim 3 , wherein the first switch is configured to transition from an activation state to a deactivation state at substantially the same time that the second switch is configured to transition from an activation state to a deactivation state during the first portion of the charging mode.
6. The bidirectional power converter of claim 3 , wherein, during the first portion of the charging mode, the first switch is pulse-width modulated at a first frequency with a first duty cycle and the second switch is pulse-width modulated at a second frequency with a second duty cycle,
wherein the first frequency is substantially the same as the second frequency, and
wherein the first duty cycle has a different duration than the second duty cycle.
7. The bidirectional power converter of claim 3 , wherein the first switch and a third switch of the first switch circuit are configured to be simultaneously active during another part of the first portion of the charging mode.
8. The bidirectional power converter of claim 1 , wherein a fourth switch and a fifth switch of the second switch circuit are configured to be simultaneously active during part of the first portion of the discharging mode.
9. The bidirectional power converter of claim 8 , wherein the fourth switch is configured to transition from a deactivation state to an activation state at substantially the same time that the fifth switch is configured to transition from a deactivation state to an activation state during the first portion of the discharging mode.
10. The bidirectional power converter of claim 8 , wherein the fourth switch is configured to transition from an activation state to a deactivation state at substantially the same time that the fifth switch is configured to transition from an activation state to a deactivation state during the first portion of the discharging mode.
11. The bidirectional power converter of claim 8 , wherein, during the first portion of the discharging mode, the fourth switch is pulse-width modulated at a fourth frequency with a fourth duty cycle and the fifth switch is pulse-width modulated at a fifth frequency with a fifth duty cycle,
wherein the fourth frequency is substantially the same as the fifth frequency, and
wherein the fourth duty cycle has a different duration than the fifth duty cycle.
12. The bidirectional power converter of claim 8 , wherein the fourth switch and a sixth switch of the second switch circuit are configured to be simultaneously active during another part of the first portion of the discharging mode.
13. The bidirectional power converter of claim 1 , wherein the first switch of the first switch circuit is configured to be inactive throughout the first portion of the charging mode.
14. The bidirectional power converter of claim 1 , wherein a switch of the second switch circuit is configured to be inactive throughout the first portion of the discharging mode.
15. The bidirectional power converter of claim 1 , wherein the first switch circuit comprises:
the first switch having a first terminal coupled to a first terminal of an input port and a second terminal coupled to a first terminal of a first winding of the transformer;
a second switch having a first terminal coupled to the first terminal of the input port and a second terminal coupled to a second terminal of the first winding of the transformer;
a third switch having a first terminal coupled to the first terminal of the first winding of the transformer and a second terminal coupled to a second terminal of the input port; and
a fourth switch having a first terminal coupled to the second terminal of the first winding of the transformer and a second terminal coupled the second terminal of the input port.
16. The bidirectional power converter of claim 15 , wherein the second switch circuit comprises:
a fifth switch having a first terminal coupled to a first terminal of an output port and a second terminal coupled to a first terminal of a second winding of the transformer;
a sixth switch having a first terminal coupled to the first terminal of the output port and a second terminal coupled to a second terminal of the second winding of the transformer;
a seventh switch having a first terminal coupled to the first terminal of the second winding of the transformer and a second terminal coupled to a second terminal of the output port; and
an eighth switch having a first terminal coupled to the second terminal of the second winding of the transformer and a second terminal coupled the second terminal of the output port.
17. A bidirectional power converter comprising:
a first switch circuit coupled to a second switch circuit via a transformer,
wherein the first switch circuit is configured to transfer power to the second switch circuit during a charging mode,
wherein the second switch circuit is configured to transfer power to the first switch circuit during a discharging mode,
wherein a first switch of the first switch circuit is configured to be active during at least part of the discharging mode, and
wherein a duty cycle of the first switch is configured to be less than 50% during the charging mode.
18. The bidirectional power converter of claim 17 , wherein a first switch of the second switch circuit is configured to be opened during a duration of the discharging mode.
19. The bidirectional power converter of claim 17 , wherein a second switch of the first switch circuit is configured to be operated so as to be active during a portion of a duty cycle of a third switch of the first switch circuit.
20. The bidirectional power converter of claim 17 , wherein a second switch of the first switch circuit is configured to be operated so as to be active during a portion of a duty cycle of a third switch and a fourth switch of the first switch circuit.
21. The bidirectional power converter of claim 17 , wherein a second switch of the second switch circuit is configured to be operated so as to be active during a portion of a duty cycle of a third switch of the second switch circuit.
22. The bidirectional power converter of claim 17 , wherein a second switch of the second switch circuit is configured to be operated so as to be active during a portion of a duty cycle of a third switch and a fourth switch of the second switch circuit.
23. The bidirectional power converter of claim 17 , wherein the first switch circuit comprises a first full-bridge switch circuit, and wherein the second switch circuit comprises a second full-bridge switch circuit.
24. The bidirectional power converter of claim 17 , wherein the first switch of the first switch circuit is configured to be opened during an entirety of a duration of the charging mode.
25. A bidirectional power converter comprising:
a first switch circuit coupled to a second switch circuit via a transformer,
wherein the first switch circuit comprises a first switch, a second switch, a third switch, and a fourth switch and is configured to transfer power to the second switch circuit during a charging mode,
wherein the second switch circuit comprises a fifth switch, a sixth switch, a seventh switch, and an eighth switch and is configured to transfer power to the first switch circuit during a discharging mode,
wherein the third switch and the fourth switch are configured to be simultaneously active during a first portion of the charging mode,
wherein the first switch and the fourth switch are configured to be simultaneously active during a second portion of the charging mode,
wherein the fourth switch and the third switch are configured to be controlled by respective pulse width modulation (PWM) signals, and
wherein a first PWM signal of the fourth switch has a pulse width that is longer or shorter than a pulse width of a second PWM signal of the third switch during the charging mode.
26. The bidirectional power converter of claim 25 , wherein the third switch and the fourth switch are configured to be simultaneously inactive for part during a third portion of the charging mode.
27. The bidirectional power converter of claim 25 , wherein the first switch circuit is configured to operate as a full bridge synchronous rectifier during a portion of the discharging mode.
28. The bidirectional power converter of claim 25 , wherein the second switch circuit is configured to operate as a full bridge synchronous rectifier during a portion of the charging mode.
29. The bidirectional power converter of claim 25 , wherein the fourth switch is configured to transition from a deactivation state to an activation state at substantially the same time that the third switch is configured to transition from a deactivation state to an activation state.
30. The bidirectional power converter of claim 25 , wherein the fourth switch is configured to transition from an activation state to a deactivation state at substantially the same time that the third switch is configured to transition from an activation state to a deactivation state.
31. The bidirectional power converter of claim 25 , wherein the fourth switch is pulse-width modulated at a first frequency and the third switch is pulse-width modulated at a second frequency, and
wherein the first frequency is substantially the same as the second frequency.
32. The bidirectional power converter of claim 25 , wherein the seventh switch and the eighth switch of the second switch circuit are configured to be simultaneously active during a portion of the discharging mode.
33. The bidirectional power converter of claim 32 , wherein the seventh switch and the sixth switch of the second switch circuit are configured to be simultaneously active another portion of the discharging mode.
34. The bidirectional power converter of claim 25 , wherein the seventh switch is configured to transition from a deactivation state to an activation state at substantially the same time that the eighth switch is configured to transition from a deactivation state to an activation state.
35. The bidirectional power converter of claim 25 , wherein the seventh switch is configured to transition from an activation state to a deactivation state at substantially the same time that the eighth switch is configured to transition from an activation state to a deactivation state.
36. The bidirectional power converter of claim 25 , wherein the seventh switch is pulse-width modulated at a fourth frequency with a fourth duty cycle and the eighth switch is pulse-width modulated at a fifth frequency with a fifth duty cycle,
wherein the fourth frequency is substantially the same as the fifth frequency, and
wherein the fourth duty cycle has a different duration than the fifth duty cycle.
37. The bidirectional power converter of claim 25 , wherein the second switch of the first switch circuit is configured to be opened during a duration of the charging mode.
38. The bidirectional power converter of claim 25 , wherein the fifth switch of the second switch circuit is configured to be opened during a duration of the discharging mode.
39. The bidirectional power converter of claim 25 , wherein the second switch of the first switch circuit is configured to be controlled by a third PWM signal during the charging mode such that the second switch is activated when the fourth switch is inactive.
40. The bidirectional power converter of claim 25 , wherein the fifth switch of the second switch circuit is configured to be controlled by a fourth PWM signal during the discharging mode such that the fifth switch is activated when the seventh switch is inactive.
41. A method of operating a bidirectional power converter comprising:
providing a first switch circuit having a full bridge configuration that is coupled to a second switch circuit having a full bridge configuration through a transformer;
operating the first switch circuit having the full bridge configuration of the bidirectional power converter in a half bridge configuration during a first portion of a charging mode;
transferring power through the transformer from the first switch circuit to the second switch circuit during the charging mode;
operating the second switch circuit having the full bridge configuration of the bidirectional power converter in a half bridge configuration during a first portion of a discharging mode; and
transferring power through the transformer from the second switch circuit to the first switch circuit during the discharging mode,
wherein a first switch of the first switch circuit is configured to be active during at least part of the discharging mode.
42. The method of claim 41 , further comprising operating the first switch circuit to operate in a full bridge synchronous rectifier configuration during the first portion of the discharging mode.
43. The method of claim 41 , further comprising operating the second switch circuit to operate as a full bridge synchronous rectifier during the first portion of the charging mode.
44. The method of claim 41 , wherein operating the first switch circuit during the first portion of the charging mode comprises operating the first switch and a second switch of the first switch circuit to be simultaneously active during part of the first portion of the charging mode.
45. The method of claim 44 , wherein operating the first switch circuit during the first portion of the charging mode further comprises operating the first switch to transition from a deactivation state to an activation state at substantially the same time that the second switch transitions from a deactivation state to an activation state during the first portion of the charging mode.
46. The method of claim 44 , wherein operating the first switch circuit during the first portion of the charging mode further comprises operating the first switch to transition from an activation state to a deactivation state at substantially the same time that the second switch transitions from an activation state to a deactivation state during the first portion of the charging mode.
47. The method of claim 44 , wherein operating the first switch circuit during the first portion of the charging mode further comprises operating the first switch and a third switch of the first switch circuit to be simultaneously active during another part of the first portion of the charging mode.
48. The method of claim 41 , wherein operating the first switch circuit during the first portion of the charging mode further comprises operating the first switch of the first switch circuit to be opened during a duration of the first portion of the charging mode.