Method and apparatus for selectively performing full bridge control and half bridge control in wireless power transfer system using LCCL-S resonant network

Patent metadata

Field	Value
Publication number	US-10974608-B2
Application number	US-201816038590-A
Country	US
Kind code	B2
Filing date	Jul 18, 2018
Priority date	Jul 19, 2017
Publication date	Apr 13, 2021
Grant date	Apr 13, 2021

Abstract

A method for selectively performing a full bridge control and a half bridge control in a WPT system using an LCCL-S resonant network may include: performing the full bridge control by controlling the switches not connected in series of the full bridge inverter to operate simultaneously; calculating a coupling coefficient of the WPT system; determining whether it is possible to switch the full bridge control to the half bridge control based on the calculated coupling coefficient; in response to determining that it is possible to switch the full bridge control to the half bridge control, calculating a load of the WPT system; and performing the half bridge control for the full bridge inverter based on the calculated load.

First claim

What is claimed is:

1. A method for selectively performing a full bridge control and a half bridge control in a wireless power transfer (WPT) system using an inductance-capacitance-capacitance-inductance-series (LCCL-S) resonant network, the WPT system including a full bridge inverter having one or more switches connected in series and one or more switches not connected in series, the method comprising:
performing the full bridge control by controlling the switches in the full bridge inverter;
calculating a coupling coefficient of the WPT system;
determining whether it is possible to switch the full bridge control to the half bridge control based on the calculated coupling coefficient;
in response to determining that it is possible to switch the full bridge control to the half bridge control, calculating a load of the WPT system; and
performing the half bridge control for the full bridge inverter based on the calculated load,
wherein the full bridge inverter comprises a first series circuit in which a first switch and a third switch are connected in series, and a second series circuit in which a fourth switch and a second switch are connected in series,
wherein the first series circuit and the second series circuit are connected in parallel with the DC power source,
wherein performing the full bridge control comprises operating the first switch or the third switch in the first series circuit and operating the fourth switch or the second switch in the second series circuit simultaneously in an ON or OFF state; and
wherein performing the half bridge control comprises:
operating the second switch in an ON state; and
operating the fourth switch in an OFF state,
the first switch and the third switch being operated alternately.

2. The method according to claim 1 , wherein the performing of the half bridge control comprises controlling one of the one or more switches connected in series of the full bridge inverter to be in an ON or OFF state at all times, causing the full bridge inverter to operate in a manner equivalent to a half bridge inverter.

3. The method according to claim 1 , wherein the determining of whether it is possible to switch the full bridge control to the half bridge control comprises:
determining a coupling coefficient range in which the half bridge control satisfies one or more design requirements; and
comparing the calculated coupling coefficient with a threshold value according to the determined coupling coefficient range.

4. The method according to claim 3 , wherein the one or more design requirements are predefined for at least one of the coupling coefficient, an output voltage, and the load of the WPT system.

5. The method according to claim 3 , wherein the performing of the half bridge control comprises:
comparing the calculated load with a control switching point predetermined according to the coupling coefficient range; and
performing the half bridge control according to the comparing of the calculated load with a control switching point.

6. The method according to claim 5 , wherein the control switching point refers to a load corresponding to a position where an efficiency of the full bridge control and an efficiency of the half bridge control intersect in the coupling coefficient range.

7. The method according to claim 1 , further comprising:
receiving, by the full bridge inverter, a direct current (DC) power source;
outputting, by the full bridge inverter, an alternating current (AC) voltage;
receiving, by a compensation network, the AC voltage from the full bridge inverter;
generating, by a compensation network, an induced electromotive force in a reception coil incorporated in a reception pad of an electric vehicle (EV);
rectifying, by a rectifier, an induced current according to the induced electromotive force;
storing, by the rectifier, a DC voltage in a capacitor; and
converting, by the a DC-DC converter, the DC voltage stored in the capacitor of the rectifier into a rated voltage of a battery equipped in the EV.

8. The method according to claim 1 , wherein the performing of the full bridge control comprises:
operating the first switch and the second switch as a first pair simultaneously in an ON or OFF state; and
operating the third switch and the fourth switch as a second pair simultaneously in an OFF or ON state,
wherein the first pair and the second pair are operated alternately.

9. An apparatus for selectively performing a full bridge control and a half bridge control in a wireless power transfer (WPT) system using an inductance-capacitance-capacitance-inductance-series (LCCL-S) resonant network, the WPT system including a full bridge inverter having one or more switches connected in series and one or more switches not connected in series, the apparatus comprising:
at least one processor; and
a memory storing at least one instruction, which when executed by the at least one processor cause the processor to:
perform the full bridge control by controlling the switches in the full bridge inverter;
calculate a coupling coefficient of the WPT system;
determine whether it is possible to switch the full bridge control to the half bridge control based on the calculated coupling coefficient;
in response to determining that it is possible to switch the full bridge control to the half bridge control, calculate a load of the WPT system; and
perform the half bridge control for the full bridge inverter based on the calculated load,
wherein the full bridge inverter comprises a first series circuit in which a first switch and a third switch are connected in series, and a second series circuit in which a fourth switch and a second switch are connected in series,
wherein the first series circuit and the second series circuit are connected in parallel with the DC power source,
wherein the processor is configured to perform the full bridge control by operating the first switch or the third switch in the first series circuit and operating the fourth switch or the second switch in the second series circuit simultaneously in an ON or OFF state; and
wherein the processor is configured to perform the half bridge control by operating the second switch in an ON state and operating the fourth switch in an OFF state, the first switch and the third switch being operated alternately.

10. The apparatus according to claim 9 , wherein the performing of the half bridge control comprises controlling one of the one or more switches connected in series of the full bridge inverter to be in an ON or OFF state at all times, causing the full bridge inverter to operate in a manner equivalent to a half bridge inverter.

11. The apparatus according to claim 9 , wherein the determining of whether it is possible to switch the full bridge control to the half bridge control:
determining a coupling coefficient range in which the half bridge control satisfies one or more design requirements; and
comparing the calculated coupling coefficient with a threshold value according to the determined coupling coefficient range.

12. The apparatus according to claim 11 , wherein the one or more design requirements are predefined for at least one of the coupling coefficient, an output voltage, and the load of the WPT system.

13. The apparatus according to claim 11 , wherein the performing of the half bridge control comprises:
comparing the calculated load with a control switching point predetermined according to the coupling coefficient range; and
performing the half bridge control according to the comparing of the calculated load with a control switching point.

14. The apparatus according to claim 13 , wherei

Assignees

• Hyundai Motor Co Ltd
• Kia Motors Corp
• Research & Business Found Sungkyunkwan Univ

Inventors

• Cha Jae Eun
• Choe Gyu Yeong
• Lee Woo Young
• Byun Jong Eun
• Kim Min Kook
• Ann Sang Joon
• Lee Byoung Kuk
• Joo Dong Myoung

Classifications

• H02J2105/37

  exchanging power with electric vehicles [EV] or with hybrid electric vehicles [HEV] · CPC title

• H02J7/90

  Regulation of charging or discharging current or voltage · CPC title

• H02M3/33571

  Half-bridge at primary side of an isolation transformer · CPC title

• H02M3/33573

  Full-bridge at primary side of an isolation transformer · CPC title

• H02M3/01

  Resonant DC/DC converters · CPC title