Power converter circuit with AC output

Patent metadata

Field	Value
Publication number	US-9484746-B2
Application number	US-201213352202-A
Country	US
Kind code	B2
Filing date	Jan 17, 2012
Priority date	Jan 17, 2012
Publication date	Nov 1, 2016
Grant date	Nov 1, 2016

Abstract

A power converter circuit includes output terminals configured to receive an external AC voltage. At least one series circuit has at least two converter units. Each converter unit includes input terminals configured to be coupled to a DC power source. Output terminals provide an AC output current. The at least one series circuit is connected between the output terminals of the power converter circuit. A voltage measurement circuit is connected between the output terminals of the power converter circuit and configured to provide at least one measurement signal that includes information related to phase and frequency of the external AC voltage. At least one of the converter units is configured to receive the at least one measurement signal and is configured to regulate the generation of the AC output current dependent on the at least one measurement signal.

First claim

What is claimed is:

1. A power converter circuit, comprising:
output terminals configured to receive an external AC voltage;
at least one series circuit with at least two DC/AC converter circuits, each DC/AC converter circuit comprising input terminals configured to be coupled to a DC power source, and output terminals for providing an AC output current, the at least one series circuit connected between the output terminals of the power converter circuit; and
a voltage divider circuit connected between the output terminals of the power converter circuit and configured to provide at least one measurement signal that includes a phase and frequency based on the external AC voltage;
wherein at least one of the DC/AC converter circuits is configured to receive the at least one measurement signal and is configured to regulate generation of the AC output current dependent on the at least one measurement signal such that a phase difference between the AC output current and the external AC voltage assumes a set value.

2. The power converter circuit of claim 1 ,
wherein the voltage divider circuit comprises a plurality of passive circuit components connected in series between the output terminals of the power converter circuit, and
wherein each passive circuit component is configured to provide one measurement signal having a phase and frequency based on the phase and frequency of the external AC voltage, and wherein each measurement signal is received by one DC/AC converter circuit.

3. The power converter circuit of claim 2 , wherein the measurement signal provided by one passive circuit component comprises a voltage across the passive circuit component or a fraction thereof.

4. The power converter circuit of claim 2 , wherein each passive circuit component includes a resistor or a capacitor.

5. The power converter circuit of claim 1 wherein the set value is zero.

6. The power converter circuit of claim 1 , wherein the at least one DC/AC converter circuit comprises:
a DC/AC converter coupled between the input terminals and the output terminals of the DC/AC converter circuit and configured to generate the AC output current with a frequency and phase that is dependent on a first reference signal; and
a control circuit configured to generate the first reference signal dependent on the at least one measurement signal and the AC output current of the DC/AC converter circuit.

7. The power converter circuit of claim 6 , wherein the DC/AC converter comprises at least one switch that comprises a GaN-HEMT.

8. The power converter circuit of claim 7 , wherein the control circuit comprises:
a phase-locked loop configured to generate a frequency dependent on the at least one measurement signal;
a phase detector configured to detect a phase difference between the phase represented by the at least one measurement signal and a phase of the AC output current and to provide a first phase difference based on the detected phase difference; and
an oscillator configured to generate the first reference signal dependent on the generated frequency and the first phase difference.

9. The power converter circuit of claim 7 ,
wherein the DC/AC converter is configured to receive an input voltage, and
wherein the control circuit is configured to generate the first reference signal dependent on the input voltage.

10. The power converter circuit of claim 7 , wherein
the DC/AC converter is coupled to a second reference signal terminal; and
the at least one DC/AC converter circuit further comprises a DC/DC converter coupled between the input terminals of the at least one DC/AC converter circuit and the DC/AC converter, the DC/DC converter configured to adjust an input voltage between the input terminals or an input current at the input terminals dependent on a second reference signal.

11. The power converter circuit of claim 10 , wherein the DC/DC converter comprises at least one switch comprising a GaN-HEMT.

12. The power converter circuit of claim 10 , further comprising a reference signal source implemented as a maximum power point tracker, the reference signal source having an input coupled to the at least one DC/AC converter circuit and an output coupled to the second reference signal terminal.

13. The power converter circuit of claim 10 , wherein the DC/DC converter is a boost converter.

14. The power converter circuit of claim 10 , wherein the DC/DC converter is a buck converter.

15. The power converter circuit of claim 1 , wherein the at least one series circuit comprises:
at least two series circuits connected in parallel, each series circuit with at least two DC/AC converter circuit s connected between the output terminals,
wherein the DC/AC converter circuit s of the at least two series circuits are coupled to the voltage divider circuit.

16. The power converter circuit of claim 6 , wherein the control circuit comprises:
a phase-locked loop having an input coupled to the at least one measurement signal;
a VCO having a control input coupled to an output of the phase-locked loop;
a subtractor having a first input coupled to an output of the phase-locked loop and an input coupled to a current measurement signal proportional to the AC output current; and
a filter coupled to an output of the subtractor.

17. A power supply system, comprising:
output terminals configured to receive an external AC voltage;
at least one series circuit with at least two DC/AC converter circuit s, each DC/AC converter circuit comprising input terminals configured to be coupled to a DC power source and output terminals for providing an AC output current, the at least one series circuit connected between the output terminals of the power supply system;
at least two DC voltage sources, each DC voltage source coupled to the input terminals of one DC/AC converter circuit; converter unit; and
a voltage divider circuit connected between the output terminals of the power supply system and configured to provide at least one measurement signal including an information on a phase and frequency of the external AC voltage;
wherein at least one of the DC/AC converter circuit s is configured to receive the at least one measurement signal, and is configured to regulate a generation of the AC output current dependent on the least one measurement signal such that a phase difference between the AC output current and the external AC voltage assumes a set value.

18. The power supply system of claim 17 , wherein each DC voltage source comprises a photovoltaic array with at least one solar cell.

19. The power supply system of claim 17 , wherein each DC voltage source comprises a fuel cell.

20. The power supply system of claim 17 wherein the set value is zero.

21. The power supply system of claim 17 , wherein the at least one DC/AC converter circuit comprises:
a DC/AC converter coupled between the input and the output terminals of the DC/AC converter circuit and configured to generate the AC output current with a frequency and phase that is dependent on a first reference signal; and
a control circuit configured to generate the first reference signal dependent on the at least one measurement signal and the AC output current of the DC/AC converter circuit.

22. The power supply system of claim 21 , wherein the control circuit comprises:
a phase-locked loop having an input coupled to the at least one measurement signal;
a VCO having a control input coupled to an output of the phase-locked loop;
a subtractor having a fir

Assignees

• Tang Yi
• Deboy Gerald
• Infineon Technologies Austria Ag

Inventors

• Tang Yi
• Deboy Gerald

Classifications

• H02J3/381

  Dispersed generators · CPC title

• H02J2101/24

  Photovoltaics · CPC title

• H02M2001/0077

  Electricity · mapped topic

• Y10T307/707

  Cross-Sectional Technologies · mapped topic

• H02M2001/0074

  Electricity · mapped topic