PULSE WIDTH MODULATION RESONANCE CONVERTER AND CHARGER FOR VEHICLE USING THE SAME

• US 20160001665A1
• Filed: 11/16/2014
• Published: 01/07/2016
• Est. Priority Date: 07/04/2014
• Status: Active Grant

• Current Assignee: Hyundai Motor Company (Hyundai Motor Group), Kia Motors Corporation (Kia Corp.), Myongji University Industry and Academia Corporation Foundation
• Original Assignee: Hyundai Motor Company (Hyundai Motor Group), Kia Motors Corporation (Kia Corp.), Myongji University Industry and Academia Corporation Foundation
• Inventors: Kim, Seok Joon, Kim, Sam Gyun, Lee, Woo Young, Kim, Jong Pil, Lee, June Young, Lee, Byung Kwon
• Granted Patent: US 10,071,637 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: B60L 53/00 Methods of charging batteries, specially adapted for electric vehicles; Charging stations or on-board charging equipment therefor; Exchange of energy storage elements in electric vehicles
• CPC Class Codes: H02J 2207/20 Charging or discharging characterised by the power electronics converter
• CPC Class Codes: H02J 7/02 for charging batteries from ac mains by converters
• CPC Class Codes: H02M 3/33507 with automatic control of the output voltage or current, e.g. flyback converters H02M3/33561, H02M3/33569 take precedence
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/7072 Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors
• CPC Class Codes: Y02T 10/92 Energy efficient charging or discharging systems for batteries, ultracapacitors, supercapacitors or double-layer capacitors specially adapted for vehicles
• CPC Class Codes: Y02T 90/14 Plug-in electric vehicles

Abstract

A pulse width modulation resonance converter is provided that includes a transformer and a switching unit including first to fourth switches electrically connected to a primary coil of the transformer and configured to convert a DC voltage into an AC voltage by a switching operation of the first to fourth switches in which each switch is switched from an off state to an on state when a voltage difference between both ends is about 0. Additionally, a rectifying unit includes an output capacitor, first to fourth diodes electrically connected to a secondary coil of the transformer, and a resonance tank having a resonance capacitor and a resonance inductor which are electrically connected to the secondary coil of the transformer. The plurality of switches connected to the primary side of the transformer perform the zero-voltage switching using the magnetized inductance of the primary side to minimize the switching loss.

Claims

1. A pulse width modulation resonance converter, comprising:

a transformer;

a switching unit that includes first to fourth switches electrically connected to a primary coil of the transformer and configured to convert a direct current (DC) voltage into an alternating current (AC) voltage by a switching operation of the first to fourth switches, wherein each switch is switched from an off state to an on state when a voltage difference between both ends is about 0; and

a rectifying unit including an output capacitor, first to fourth diodes electrically connected to a secondary coil of the transformer, and a resonance tank having a resonance capacitor and a resonance inductor electrically connected to the secondary coil of the transformer.

2. The pulse width modulation resonance converter of claim 1, wherein:

a first end of the secondary coil of the transformer is electrically connected to a contact point of the first and second diodes,

the resonance tank is electrically connected between a second end of the secondary coil of the transformer and a contact point of the third and fourth diodes, and

the output capacitor is electrically connected between the contact point of the first and fourth diodes and the contact point of the second and third diodes.

3. The pulse width modulation resonance converter of claim 2, wherein:

a first end of the primary coil of the transformer is electrically connected to a contact point of the first and second switches connected to each other in series,

a second end of the primary coil of the transformer is electrically connected to a contact point of the third and fourth switches connected to each other in series, and

an input capacitor is electrically connected between the first switch and the second switch.

4. The pulse width modulation resonance converter of claim 3, wherein in a first operation mode in which the first switch and the third switch are turned on and the second switch and the fourth switch are turned off, a primary current of the transformer flows on a path of the input capacitor, the first switch, and the third switch, and a resonance current by the resonance tank flows in the secondary side of the transformer.

5. The pulse width modulation resonance converter of claim 4, wherein in a second operation mode in which the first switch is switched from the on state to the off state, the third switch is in the on state, and the second switch and the fourth switch are maintained in the off state, a voltage difference of the second switch is about 0, and a period of the second operation mode is maintained for a time period less than a time period of the first operation mode.

6. The pulse width modulation resonance converter of claim 5, wherein in a third operation mode in which the second switch is switched from the off state to the on state, the third switch is in the on state, and the first switch and the fourth switch are maintained in the off state while the voltage difference of the second switch is about 0, a voltage of both ends of the transformer is about 0, and a resonance current of which an amplitude is reduced by the resonance tank flows in the secondary side of the transformer.

7. The pulse width modulation resonance converter of claim 6, wherein in a fourth operation mode in which the third switch is switched from the on state to the off state, the second switch is in the on state, and the first switch and the fourth switch are maintained in the off state, a voltage difference of both ends of the fourth switch is about 0, and a time period of the fourth operation mode is maintained for a time period less than a time period of the third operation mode.

8. A charger for a vehicle that charges a high voltage battery supplying power to a motor generator of the vehicle and a low voltage battery supplying the power to an electric field of the vehicle, the charger comprising:

an alternating current-direct current (AC/DC) converter configured to convert an input AC voltage into a DC voltage;

a first converter including a plurality of switches formed at a primary side of a transformer, and a resonance inductor and a resonance capacitor formed at a secondary side of the transformer, and configured to generate a first voltage for charging the high voltage battery by adjusting a level of a DC voltage output from the AC/DC converter; and

a low voltage supply unit configured to generate a second voltage to charge the low voltage battery by setting an output voltage of the first converter or an output voltage of the high voltage battery as a first fixed voltage and reducing the output voltage based on the first fixed voltage.

9. The charger of claim 8, wherein the low voltage supply unit includes:

a fixed voltage generator configured to maintain the output voltage of the first converter or the output voltage of the high voltage battery at the first fixed voltage, and

a low voltage DC/DC converter configured to charge the low voltage battery by the second voltage, after converting the first fixed voltage output from the fixed voltage generator into the second voltage by adjusting a duty ratio.

10. The charger of claim 9, wherein the fixed voltage generator includes:

a first switch electrically connected to an output terminal of the first converter and a first end of the high voltage battery,

a diode electrically connected to the first switch and a second end of the high voltage battery, and

an inductor electrically connected to the output terminal of the first converter and the first end of the high voltage battery.

11. The charger of claim 10, wherein:

in a first mode in which the high voltage battery is charged, the first switch is in an on state, and

in a second mode in which the low voltage battery is charged, the first switch, the diode, and the inductor operate as a buck DC/DC converter.

12. The charger of claim 10, wherein the fixed voltage generator further includes:

a second switch connected to the first switch in parallel and electrically connected to the output terminal of the first converter and the first end of the high voltage battery.

13. The charger of claim 12, wherein:

in the first mode in which the high voltage battery is charged, the second switch is in an on state, and

in the second mode in which the low voltage battery is charged, the second switch is in an off state, and the first switch, the diode, and the inductor operate as a buck DC/DC converter.

14. The charger of claim 13, wherein the first switch is an MOSFET, and the second switch is a relay.

15. The charger of claim 14, wherein the low voltage supply unit is configured to maintain the first fixed voltage based on the output voltage of the first converter while the vehicle is stopped, and maintain the first fixed voltage based on the output voltage of the high voltage battery while the vehicle is traveling.

16. The charger of claim 14, wherein the first converter includes:

a transformer;

a switching unit that includes first to fourth switches electrically connected to a primary coil of the transformer and configured to convert a DC voltage into an AC voltage by a switching operation of the first to fourth switches in which each switch is switched from an off state to an on state when a voltage difference between both ends is about 0; and

a rectifying unit including first to fourth diodes electrically connected to a secondary coil of the transformer, a resonance tank having a resonance capacitor and a resonance inductor which are electrically connected to the secondary coil of the transformer, and an output capacitor.

17. The charger of claim 16, wherein:

a first end of the secondary coil of the transformer is electrically connected to a contact point of the first and second diodes,

the resonance tank is electrically connected between a second end of the secondary coil of the transformer and a contact point of the third and fourth diodes, and

the output capacitor is electrically connected between the contact point of the first and fourth diodes and the contact point of the second and third diodes.

18. The charger of claim 17, wherein:

a first end of the primary coil of the transformer is electrically connected to a contact point of the first and second switches connected to each other in series,

a second end of the primary coil of the transformer is electrically connected to a contact point of the third and fourth switches connected to each other in series, and

an input capacitor is electrically connected between the first switch and the second switch.