MODULAR MULTI-PULSE TRANSFORMER RECTIFIER FOR USE IN ASYMMETRIC MULTI-LEVEL POWER CONVERTER

• US 20110013428A1
• Filed: 09/27/2010
• Published: 01/20/2011
• Est. Priority Date: 09/24/2008
• Status: Active Grant

• Current Assignee: Alex Skorcz, Chao Hsu Liao, Enrique Ledezma, Mehdi Abolhassani, Ryan Edwards, Thomas Keister
• Original Assignee: Alex Skorcz, Chao Hsu Liao, Enrique Ledezma, Mehdi Abolhassani, Ryan Edwards, Thomas Keister
• Inventors: Liao, Chao Hsu, ABOLHASSANI, MEHDI, Edwards, Ryan, Ledezma, Enrique, Keister, Thomas, Skorcz, Alex
• Granted Patent: US 8,045,346 B2
• Time in Patent Office: Days
• US Class Current: 363/37
• CPC Class Codes: H02M 5/4585 having a rectifier with controlled elements
• CPC Class Codes: H02M 7/49 Combination of the output voltage waveforms of a plurality of converters

Abstract

In one embodiment, the present invention includes a system having multiple modular transformers each including a primary winding coupled to an input power source and phase-shifted secondary windings each coupled to a power cell. The system further includes different phase output lines coupled to a load. These lines may include first, second and third phase output lines.

Claims

1. A system comprising:

a plurality of modular transformers each including a primary winding coupled to an input power source and a plurality of phase-shifted secondary windings each coupled to a power cell;

a first phase output line having at least a first level power cell and a second level power cell, wherein a first one of the modular transformers has a first plurality of the phase-shifted secondary windings coupled to the first level power cell and a second plurality of the phase-shifted secondary windings coupled to the second level power cell; and

a second phase output line having at least a first level power cell and a second level power cell, wherein a second one of the modular transformers has a first plurality of the phase-shifted secondary windings coupled to the first level power cell and a second plurality of the phase-shifted secondary windings coupled to the second level power cell.

2. The system of claim 1, wherein the first phase output line has a third level power cell, and wherein at least one of the phase-shifted secondary windings of the first modular transformer is coupled to the third level power cell.

3. The system of claim 2, wherein the first level power cell is of a higher voltage than the second level power cell, and the second level power cell is of a higher voltage than the third level power cell, and wherein each of the plurality of modular transformers are of the same output level.

4. The system of claim 1, wherein the first level power cell includes a rectifier stack having a greater number of diodes than a rectifier stack of the second level power cell, and wherein each diode of the first power cell is coupled to one of the first plurality of phase-shifted secondary windings.

5. The system of claim 1, wherein the primary winding of the plurality of modular transformers is a phase-shifted primary winding having a phase shift based on a phase shift of the phase-shifted secondary windings and a number of the plurality of modular transformers.

6. The system of claim 5, wherein the phase shift of the phase-shifted α

_sec/N_t, wherein N_t is the number of the plurality of modular transformers, and α

_sec corresponds to the phase shift between two of the phase-shifted secondary windings of a corresponding modular transformer, and is according to 360/2 N_ph N_s, where N_ph is a number of phases of the input power source and N_s is an integer number of the phase-shifted secondary windings in each of the modular transformers.

7. The system of claim 1, further comprising a third phase output line having at least a first level power cell and a second level power cell, wherein a third one of the modular transformers has a first plurality of the phase-shifted secondary windings coupled to the first level power cell, and a second plurality of the phase-shifted secondary windings coupled to the second level power cell.

8. A method comprising:

receiving power from a utility connection in a plurality of modular transformers each including at least one phase-shifted primary set of windings and a plurality of secondary sets of windings;

providing power from a first plurality of the secondary sets of windings of at least one of the modular transformers to a plurality of first level power cells, wherein a first one of the first level power cells is coupled to a first phase output line, a second one of the first level power cells is coupled to a second phase output line, and a third one of the first level power cells is coupled to a third phase output line; and

providing power from a second plurality of the secondary sets of windings of at least one of the modular transformers to a plurality of second level power cells, wherein a first one of the second level power cells is coupled to the first phase output line, a second one of the second level power cells is coupled to the second phase output line, and a third one of the second level power cells is coupled to the third phase output line, and any of the first level power cells and the second level power cells can be coupled to any of the secondary sets of windings of any of the plurality of modular transformers.

9. The method of claim 8, further comprising providing power from at least one of the secondary sets of windings of at least one of the modular transformers to a plurality of third level power cells, wherein a first one of the third level power cells is coupled to the first phase output line, a second one of the third level power cells is coupled to the second phase output line, and a third one of the third level power cells is coupled to the third phase output line, and any of the third level power cells can be coupled to any of the secondary sets of windings of any of the plurality of modular transformers.

10. The method of claim 8, further comprising rectifying the power in the first level power cells, each including one of a first plurality of rectifiers coupled to one of the secondary sets of windings, and rectifying the power in the second level power cells, including one of a second plurality of rectifiers each coupled to one of the sets of secondary windings, the second plurality of rectifiers less than the first plurality of rectifiers.

11. The method of claim 8, further comprising coupling at least one of the secondary sets of windings of a first set of the modular transformers to each of the first level power cells and coupling at least one of the secondary sets of windings of a second set of the modular transformers to each of the second level power cells.

12. The apparatus of claim 11, further comprising coupling each of the secondary sets of windings of one of the modular transformers to one of the third level power cells.

13. A system comprising:

at least one first modular transformer including at least one primary winding to couple to a utility connection and a plurality of phase-shifted secondary windings each to couple to a third level power cell of one of a plurality of phase output lines each to output AC power to one of the plurality of phase output lines;

a plurality of second modular transformers each including at least one primary winding to couple to the utility connection and a plurality of phase-shifted secondary windings each to couple to a second level power cell of one of the phase output lines each to output AC power to one of the plurality of phase output lines, wherein multiple ones of the phase-shifted secondary windings of the second modular transformers are to couple to the same second level power cell; and

a plurality of third modular transformers each including at least one primary winding to couple to the utility connection and a plurality of phase-shifted secondary windings each to couple to a first level power cell of one of the phase output lines each to output AC power to one of the plurality of phase output lines, wherein multiple ones of the phase-shifted secondary windings of the third modular transformers are to couple to the same first level power cell.

14. The system of claim 13, wherein more of the third modular transformer phase-shifted secondary windings are to couple to the same first level power cell than the second modular transformer phase-shifted secondary windings to couple to the same second level power cell.

15. The system of claim 13, wherein the plurality of third modular transformers is greater than the plurality of second modular transformers.

16. The system of claim 13, wherein each phase-shifted secondary winding of each of the at least one first modular transformer, the plurality of second modular transformers and the plurality of third modular transformers is to output the same voltage.