Power converter arrangement with increased surge voltage robustness

Patent metadata

Field	Value
Publication number	US-11916472-B2
Application number	US-202117534519-A
Country	US
Kind code	B2
Filing date	Nov 24, 2021
Priority date	Dec 7, 2020
Publication date	Feb 27, 2024
Grant date	Feb 27, 2024

Abstract

A method for operating a power converter arrangement and a corresponding controller are disclosed. The method includes operating the power converter arrangement in a surge mode, when a DC link voltage of the power converter arrangement reaches a first voltage threshold. The power converter includes a first power converter having an input and an output; a second power converter having an input and an output; and a DC link capacitor circuit coupled to the output of the first power converter and the input of the second power converter and providing the DC link voltage. Operating the power converter arrangement in the surge mode includes: deactivating the second power converter; and operating, at least temporarily, the first power converter in a reverse mode to transfer energy from the DC link capacitor circuit to the input of the first power converter.

First claim

What is claimed is:

1. A method, comprising:
operating a power converter arrangement in a surge mode, wherein the power converter arrangement comprises: a first power converter comprising an input and an output; a second power converter comprising an input and an output; and a DC link capacitor circuit coupled to the output of the first power converter and the input of the second power converter and providing a DC link voltage, wherein the surge mode occurs when a surge pulse at the input of the first power converter causes the DC link voltage to reach a first voltage threshold,
wherein operating the power converter arrangement in the surge mode comprises:
deactivating the second power converter when the DC link voltage reaches the first voltage threshold; and
operating, at least temporarily, the first power converter in a reverse mode to transfer energy from the DC link capacitor circuit to the input of the first power converter,
wherein operating, at least temporarily, the first power converter in the reverse mode comprises:
deactivating the first power converter when the DC link voltage reaches the first voltage threshold; and
operating the first power converter in the reverse mode when the surge pulse has decayed.

2. The method of claim 1 , wherein operating the first power converter in the reverse mode when the surge pulse has decayed comprises operating the first power converter in the reverse mode when current driven by the surge pulse through the first power converter essentially reaches zero.

3. The method of claim 2 , further comprising monitoring input current of the first power converter to determine when the current driven by the surge pulse through the first power converter essentially reaches zero.

4. The method of claim 2 , further comprising monitoring input current of the DC link capacitor circuit to determine when the current driven by the surge pulse through the first power converter essentially reaches zero.

5. The method of claim 1 , further comprising monitoring the DC link voltage to determine when the current driven by the surge pulse through the first power converter essentially reaches zero.

6. The method of claim 5 , further comprising determining that the current driven by the surge pulse through the first power converter essentially reaches zero when a time derivative of the DC link voltage reaches zero.

7. The method of claim 1 , further comprising:
changing from the surge mode to a normal operating mode of the power converter arrangement when the DC link voltage falls below a second voltage threshold,
wherein operating the power converter arrangement in the normal operating mode comprises:
transferring energy, by the first power converter, from the input of the first power converter to the output of the first power converter; and
transferring energy, by the second power converter, from the input of the second power converter to the output of the second power converter.

8. The method of claim 7 , wherein transferring energy, by the first power converter, from the input of the first power converter to the output of the first power converter comprise regulating the DC link voltage, and wherein transferring energy, by the second power converter, from the input of the second power converter to the output of the second power converter comprises regulating one of an output voltage or an output current of the second power converter.

9. The method of claim 1 , wherein the second voltage threshold is equal to or smaller than the first voltage threshold.

10. The method of claim 1 , wherein the power converter arrangement has a DC link voltage reference, and wherein the first voltage threshold is at least 10% higher than the DC link voltage reference.

11. The method of claim 1 , wherein the second power converter comprises at least one half-bridge with two electronic switches, wherein the at least one half-bridge is coupled to the input of the second power converter, and wherein deactivating the second power converter comprises switching off the two electronic switches of the at least one half-bridge.

12. The method of claim 1 , wherein the first power converter is an AC/DC converter and the second power converter is a DC/DC converter.

13. The method of claim 12 , wherein the first power converter is a PFC converter.

14. The method of claim 12 , wherein the second power converter is selected from the group consisting of:
an LLC converter;
a phase shift ZVS (zero voltage switching) converter; and
a two-transistor-forward converter.

15. A controller configured to operate a power converter arrangement in a surge mode, wherein the surge mode occurs when a surge pulse at an input of a first power converter of the power converter arrangement causes a DC link voltage of a DC link capacitor circuit of the power converter arrangement to reach a first voltage threshold,
wherein operating the power converter arrangement in the surge mode comprises:
at least temporarily, operating the first power converter in a reverse mode to transfer energy from the DC link capacitor circuit to an input of the power converter arrangement; and
deactivating a second power converter coupled between the DC link capacitor circuit and an output of the power converter arrangement when the DC link voltage reaches the first voltage threshold,
wherein at least temporarily operating the first power converter in the reverse mode comprises:
deactivating the first power converter when the DC link voltage reaches the first voltage threshold; and
operating the first power converter in the reverse mode when the surge pulse has decayed.

16. The controller of claim 15 , wherein the controller is configured to operate the first power converter in the reverse mode when current driven by the surge pulse through the first power converter essentially reaches zero.

17. The controller of claim 16 , wherein the controller is further configured to monitor input current of the first power converter to determine when the current driven by the surge pulse through the first power converter essentially reaches zero.

18. The controller of claim 15 , wherein the controller is further configured to monitor the DC link voltage to determine when the current driven by the surge pulse through the first power converter essentially reaches zero.

19. The controller of claim 18 , wherein the controller is configured to determine that the current driven by the surge pulse through the first power converter essentially reaches zero when a time derivative of the DC link voltage reaches zero.

Assignees

• Infineon Technologies Austria Ag

Inventors

• Deboy Gerald

Classifications

• H02M1/36

  Means for starting or stopping converters · CPC title

• H02M1/4233

  using a bridge converter comprising active switches · CPC title

• H02M3/33573

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

• H02M1/007

  Plural converter units in cascade (push-pull DC/DC converters with pre-regulator H02M3/3374; DC-AC converters following a DC-DC stage including a high frequency transformer H02M7/4807; DC-AC converters following a DC-DC conversion stage generating periodically varying voltages H02M7/4826) · CPC title

• H02M1/322

  Means for rapidly discharging a capacitor of the converter for protecting electrical components or for preventing electrical shock · CPC title