Resonant power converter

• US 10,454,377 B2
• Filed: 07/18/2013
• Issued: 10/22/2019
• Est. Priority Date: 01/19/2011
• Status: Active Grant

• Current Assignee: ABB BV (ABB Limited)
• Original Assignee: ABB BV (ABB Limited)
• Inventors: Kardolus, Menno, Schijffelen, Jos, Groninger, Mark, Van Casteren, Dolf
• Primary Examiner(s): Laxton, Gary L
• Assistant Examiner(s): Rivera-Perez, Carlos O
• Application Number:
  US13/945,465
• Publication Number:
  US 20130301307A1
• Time in Patent Office: 2,287 Days
• Field of Search: 363 15- 2118, 363 40- 48, 363 5612, 363 89, 363 95- 99, 363131-134, 323205-211, 323222-226, 323235, 323236, 323271-275, 323282-287, 323299, 323351, 323319, 307 31- 35
• CPC Class Codes: H02M 1/0058 by employing soft switching techniques, i.e. commutation of transistors when applied voltage is zero or when current flow is zero using an auxiliary actively switched resonant commutation circuit connected to an intermediate DC voltage or between two push-pull branches of an inverter bridge H02M7/4811; in resonant inverters H02M7/4815; in inverters operating from a resonant DC source H02M7/4826
• CPC Class Codes: H02M 3/01 Resonant DC/DC 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: H02M 3/33571 Half-bridge at primary side of an isolation transformer
• CPC Class Codes: H02M 3/33573 Full-bridge at primary side of an isolation transformer
• CPC Class Codes: H02M 3/3376 with automatic control of output voltage or current
• CPC Class Codes: H02M 7/4815 Resonant converters H02M7/4811 and H02M7/4826 take precedence
• 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 resonant power converter includes a resonance tank formed by a capacitance component and an inductance component, at least two switches connected to the resonance tank and a voltages source in a bridge configuration, a number of snubber capacitors connected in parallel to each of the switches, a controller configured to control ON and OFF timings of the at least two switches so as to excite the resonance tank, and a voltage sensor configured to sense a voltage drop across at least one of the switches. The controller is configured to switch the at least one of the switches to the ON state when the absolute value of the sensed voltage drop reaches a minimum.

Claims

1. A resonant power converter comprising:

a rectifier receiving an AC input voltage and outputting a fluctuating DC input voltage with a waveform composed of sinusoidal half waves;

a resonance tank formed by a first set of capacitors of equal capacitances and an inductor connected to a midpoint between the first set of capacitors;

at least two switches connected to the resonance tank and the rectifier in a bridge configuration, the fluctuating DC input voltage being supplied from the rectifier to the at least two switches without a capacitor being disposed therebetween, and the inductor being connected at a midpoint between the at least two switches, the inductor thereby being connected between the at least to switches and the first set of capacitors;

a plurality of snubber capacitors connected in parallel to each of the switches;

a second set of capacitors of equal capacitances, wherein the first set of capacitors is parallel to the at least two switches, and the second set of capacitors is parallel to the first set of capacitors;

a transformer whose primary side is connected at one end to the midpoint between the first set of capacitors and to the inductor and at another end to a midpoint between the second set of capacitors;

a controller configured to control ON and OFF timings of the at least two switches so as to excite the resonance tank; and

a voltage sensor configured to sense a voltage drop across at least one of the switches,

wherein the controller is configured to switch the at least one of the switches to the ON state when the absolute value of the sensed voltage drop reaches a minimum,

wherein the voltage sensor is configured to sense the voltage drop across the at least one of the switches at a junction point between the at least two switches,

wherein the controller is configured to control an input current of the converter in accordance with a sinusoidal waveform,

wherein the controller is configured to determine switch timings of the switches into the OFF state on the basis of a clock signal with a given frequency, and

wherein the clock signal is synchronized with one of the AC input voltage and the fluctuating DC input voltage.

2. The converter according to claim 1, wherein the frequency is variable for adjusting at least one of an output power or an output current of the converter to a given demand.

3. The converter according to claim 2, wherein the controller is configured to feedback-control the output current of the converter.

4. The converter according to claim 3, wherein the controller is configured to feedback-control the input current.

5. The converter according to claim 4, wherein the controller has nested feedback loops for controlling both the output current and the input current of the converter.

6. The converter according to claim 2, wherein the controller has a mode of operation in which bursts of ON and OFF periods of the switches alternate with breaks in which all switches are in the OFF state.

7. The converter according to claim 6, wherein the controller is configured to feedback-control the output current of the converter.

8. The converter according to claim 7, wherein the controller is configured to feedback-control the input current.

9. The converter according to claim 1, wherein the ON periods of the at least two switches are skipped at timings that are offset relative to one another.

10. The converter according to claim 1, wherein the controller has a mode of operation in which bursts of ON and OFF periods of the switches alternate with breaks in which all switches are in the OFF state.

11. The converter according to claim 1, comprising:

an LCC topology with parallel load.

12. The converter according to claim 1, wherein the controller has nested feedback loops for controlling both an output current and the input current of the converter.

13. The converter according to claim 1, wherein the controller has a mode of operation in which isolated ON periods of the at least two switches are skipped in a periodic time pattern for reducing an output power of the converter.