SINGLE-PHASE SELF-DRIVEN FULL-BRIDGE SYNCHROUNOUS RECTIFICATION

• US 20100046259A1
• Filed: 08/20/2008
• Published: 02/25/2010
• Est. Priority Date: 08/20/2008
• Status: Active Grant

• Current Assignee: ConvenientPower HK Limited
• Original Assignee: ConvenientPower HK Limited
• Inventors: Ho, Wing Choi, Liu, Xun, Hui, Ron Shu
• Granted Patent: US 8,942,018 B2
• Time in Patent Office: Days
• US Class Current: 363/126
• CPC Class Codes: H02M 7/217 using semiconductor devices only
• CPC Class Codes: H02M 7/2195 the switches being synchronously commutated at the same frequency of the AC input voltage
• CPC Class Codes: Y02B 70/10 Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes

Abstract

A full-bridge rectifier is configured to provide synchronous rectification with either a current-source or a voltage-source. The rectifier has an upper branch and a lower branch and two current loops, with each of the branches including voltage- or current-controlled active switches, diodes or combinations thereof that are selected such that each loop includes one active switch or diode from the upper branch and one active switch or diode from the lower branch, and each current loop comprises at least one diode or current-controlled active switch, and at least one voltage- or current-controlled active switch is included in one of the upper or lower branches.

Claims

1. An energy receiving circuit for use in an inductive power transfer system, comprising:

a winding;

a capacitor connected with said winding to form a current-source or a voltage-source, said current- or voltage-source being input to a full-bridge rectifier configured to provide synchronous rectification, said rectifier comprising an upper branch and a lower branch and two current loops, each said branch comprising voltage- or current-controlled active switches, diodes or combinations thereof selected such that each said loop includes one active switch or diode from said upper branch and one active switch or diode from said lower branch, and wherein each said current loop comprises at least one diode or current-controlled active switch, and wherein at least one voltage- or current-controlled active switch is included in one of said upper or lower branches.

2. A circuit as claimed in claim 1 wherein said voltage- and current-controlled active switches are self-driven and do not require external control signals.

3. A circuit as claimed in claim 2 wherein a said voltage-controlled active switch is driven by an input ac voltage provided to said switch by a gate drive circuit.

4. A circuit as claimed in claim 2 wherein a said current-controlled active switch is driven by sensing the current direction of the switch and providing a signal to a gate drive circuit dependent on the current direction.

5. A circuit as claimed in claim 1 wherein said upper branch comprises two voltage-controlled active switches and said lower branch comprises two current-controlled active switches, or one current-controlled switch and one diode, or two diodes.

6. A circuit as claimed in claim 1 wherein said upper branch comprises one voltage-controlled active switch and one current-controlled active switch or diode, and the lower branch comprises one voltage-controlled active switch and one current-controlled active switch or diode, wherein said current-controlled active switch(es) or diode(s) are not provided in the same current loop.

7. A circuit as claimed in claim 1 wherein said upper branch comprises one voltage-controlled active switch and one current-controlled active switch or diode, and the lower branch comprises two current-controlled active switches, or one current-controlled switch and one diode, or two diodes.

8. A circuit as claimed in claim 1 wherein said upper branch comprises two current-controlled active switches, or one current-controlled switch and one diode, or two diodes, and the lower branch comprises two voltage-controlled active switches.

9. A circuit as claimed in claim 1 wherein said upper branch comprises two current-controlled active switches, or one current-controlled switch and one diode, or two diodes, and the lower branch comprises one voltage-controlled active switch and one current-controlled switch or one diode.

10. A circuit as claimed in claim 1 comprising a current-controlled active switch in either the upper or lower branch and three diodes.

11. A circuit as claimed in claim 1 comprising four current-controlled active switches.

12. A circuit as claimed in claim 1 wherein said capacitor is connected in series with said winding to form a current source and said rectifier is configured to receive a current source.

13. A circuit as claimed in claim 1 wherein said capacitor is connected in parallel to said winding to form a voltage source and said rectifier is configured to receive said voltage source.

14. A circuit as claimed in claim 1 wherein said active switches comprise power MOSFETs.

16. A circuit as claimed in claim 1 comprising more than one said current source connected in parallel.

15. (canceled)