Multi-channel inverter systems

Patent metadata

Field	Value
Publication number	US-9923485-B2
Application number	US-201514933723-A
Country	US
Kind code	B2
Filing date	Nov 5, 2015
Priority date	Nov 5, 2015
Publication date	Mar 20, 2018
Grant date	Mar 20, 2018

Abstract

A system comprises a first T-type inverter connected to a dc power source, a second T-type inverter connected to the dc power source, wherein the second T-type inverter is configured to operate with a first phase shift from the first T-type inverter, a third T-type inverter connected to the dc power source, wherein the third T-type inverter is configured to operate with a second phase shift from the second T-type inverter, a coupled inductor having a first input, a second input and a third input connected to the first T-type inverter, the second T-type inverter and the third T-type inverter respectively and an output filter coupled to the output of the coupled inductor.

First claim

What is claimed is:

1. A system comprising:
a first inverter comprising:
a plurality of power processing channels coupled between an input dc power source and a first coupled inductor, wherein each channel is configured to invert a dc waveform into an ac waveform with a phase shift equal to 360 degrees divided by N, wherein N is an odd integer;
the first coupled inductor comprising a plurality of windings, wherein:
each winding has a first terminal connected to a corresponding power processing channel; and
second terminals of the plurality of windings are connected together; and

an output filter having an input connected to the second terminals of the plurality of windings.

2. The system of claim 1 , wherein the first coupled inductor comprises:
a magnetic core comprising a first leg, a second leg and a third leg;
a first winding of the first coupled inductor wound around the first leg;
a second winding of the first coupled inductor wound around the second leg; and
a third winding of the first coupled inductor wound around the third leg.

3. The system of claim 2 , wherein:
the first winding of the first coupled inductor and the second winding of the first coupled inductor are wound in a same direction; and
the second winding of the first coupled inductor and the third winding of the first coupled inductor are wound in a same direction.

4. The system of claim 1 , wherein:
the windings of the first coupled inductor are negatively coupled to each other.

5. The system of claim 1 , wherein:
each power processing channel is a three-level T-type inverter.

6. The system of claim 5 , wherein the three-level T-type inverter comprises:
a first switch and a second switch connected in series between two terminals of the input dc power source; and
a third switch and a fourth switch connected back-to-back between a common node of the first switch and the second switch, and a neutral point.

7. The system of claim 1 , wherein:
the output filter comprises an output capacitor directly connected to a terminal of the first coupled inductor.

8. The system of claim 1 , further comprising:
a second inverter coupled between the input dc power source and a second coupled inductor;
a third inverter coupled between the input dc power source and a third coupled inductor; and
a fourth coupled inductor having a first input connected to an output terminal of the first coupled inductor, a second input connected to an output terminal of the second coupled inductor, a third input connected to an output terminal of the third coupled inductor.

9. The system of claim 8 , wherein:
the second coupled inductor and the third coupled inductor have a same structure as the first coupled inductor.

10. A system comprising:
a first T-type inverter connected to a dc power source;
a second T-type inverter connected to the dc power source, wherein the second T-type inverter is configured to operate with a first phase shift from the first T-type inverter;
a third T-type inverter connected to the dc power source, wherein the third T-type inverter is configured to operate with a second phase shift from the second T-type inverter;
a coupled inductor having a first input, a second input and a third input connected to the first T-type inverter, the second T-type inverter and the third T-type inverter respectively, wherein the coupled inductor comprises:
a magnetic core comprising a first leg, a second leg and a third leg;
a first winding wound around the first leg;
a second winding wound around the second leg; and
a third winding wound around the third leg, wherein output terminals of the first winding, the second winding and the third winding are connected together to form an output of the coupled inductor; and

an output filter coupled to the output of the coupled inductor.

11. The system of claim 10 , wherein:
the first winding is negatively coupled to the second winding;
the second winding is negatively coupled to the third winding; and
the third winding is negatively coupled to the first winding.

12. The system of claim 10 , wherein:
the output filter is connected between the coupled inductor and an ac source.

13. The system of claim 12 , wherein:
the output filter comprises an output capacitor and an output inductor, and wherein:
the output inductor is connected between the coupled inductor and the ac source; and
the output capacitor is connected to a common node of the output inductor and the coupled inductor.

14. The system of claim 10 , wherein the first T-type inverter comprises:
a first switching element;
a second switching element, wherein:
the second switching element and the first switching element are connected in series; and
a common node of the first switching element and the second switching element is an output of the first T-type inverter; and

a first isolation switch comprising two back-to-back connected switching elements, wherein the first isolation switch is coupled between the output of the first T-type inverter and ground.

15. The system of claim 10 , wherein:
the first phase shift is equal to 360 degrees divided by N, and wherein N is an odd integer.

16. The system of claim 10 , wherein:
the second phase shift is equal to the first phase shift.

17. A three-phase inverter system comprising:
a first phase comprising a plurality of first inverters connected together through a first coupled inductor, wherein:
the first coupled inductor comprises a plurality of first windings negatively coupled to each other; and
the plurality of first inverters are configured to operate with a phase shift from one another;

a second phase comprising a plurality of second inverters connected together through a second coupled inductor;
a third phase comprising a plurality of third inverters connected together through a third coupled inductor; and
a fourth coupled inductor having a first winding connected between the first coupled inductor and a first output filter, a second winding connected between the second coupled inductor and a second output filter and a third winding connected between the third coupled inductor and a third output filter.

18. The three-phase inverter system of claim 17 , wherein:
the first winding of the fourth coupled inductor is negatively coupled to the second winding of the fourth coupled inductor;
the second winding of the fourth coupled inductor is negatively coupled to the third winding of the fourth coupled inductor; and
the third winding of the fourth coupled inductor is negatively coupled to the first winding of the fourth coupled inductor.

19. The three-phase inverter system of claim 17 , wherein:
the first inverters are three-level T-type inverters.

20. The three-phase inverter system of claim 17 , wherein the fourth coupled inductor comprises:
a magnetic core comprising a first leg, a second leg and a third leg;
a first winding wound around the first leg;
a second winding wound around the second leg; and
a third winding wound around the third leg.

Assignees

• Futurewei Technologies Inc

Inventors

• Fu Dianbo
• Liu Yunfeng

Classifications

• H02M7/49

  Combination of the output voltage waveforms of a plurality of converters · CPC title

• H02M7/487 Primary

  Neutral point clamped inverters · CPC title

• H02M7/537 Primary

  using semiconductor devices only, e.g. single switched pulse inverters · CPC title

• H02M1/0064

  Magnetic structures combining different functions, e.g. storage, filtering or transformation · CPC title

• Y02B70/10

  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 · CPC title