Moving magnetic field electric power converter

• US 4,870,558 A
• Filed: 05/06/1988
• Issued: 09/26/1989
• Est. Priority Date: 05/06/1988
• Status: Expired due to Term

• Current Assignee: John W. Luce
• Original Assignee: John W. Luce
• Inventors: Luce, John W.
• Primary Examiner(s): Wong, Peter S.
• Application Number:
  US07/190,719
• Time in Patent Office: 508 Days
• Field of Search: 363/43, 363/44, 363/45, 363/46, 363/84, 363/85, 363/87, 363/88, 363/126, 363/128, 363/129, 363/135-137
• US Class Current: 363/87
• CPC Class Codes: H01F 29/12 having movable coil, winding, or part thereof; having movable shield
• CPC Class Codes: H01F 30/12 Two-phase, three-phase or polyphase transformers
• CPC Class Codes: H02M 1/12 Arrangements for reducing harmonics from ac input or output
• CPC Class Codes: H02M 7/155 using semiconductor devices only
• CPC Class Codes: H02M 7/49 Combination of the output voltage waveforms of a plurality of converters
• CPC Class Codes: H02M 7/757 using semiconductor devices only

Abstract

An electric power converter operable by means of a rotating or moving magnetic field having a substantially constant flux density or of a substantially constant magnitude. The electric power converter functions as a AC to DC, DC to AC or DC converter, or as a phase changer/phase shifter or a voltage adjuster. A feature of the converter is the continuous supply of power from the primary phases in contrast to prior art converters in which only the phase having the highest voltage supplies power at any one time. Harmonic current distortion is, therefore, substantially reduced.

Claims

1. A method for electric power conversion, comprising the steps of:

producing a polyphase moving magnetic field having substantially constant flux density by means of a first polyphase winding when input power is supplied to said first polyphase winding; and

magnetically coupling a second winding with said moving magnetic field to produce power output.

2. The method as set forth in claim 1, wherein said second winding comprises a second polyphase winding and wherein said power output comprises polyphase power output having a phase output for each phase of said second polyphase winding.

3. The method as set forth in claim 1, wherein said step of producing a polyphase moving magnetic field comprises producing a polyphase moving magnetic field in a ferromagnetic material.

4. The method as set forth in claim 1, wherein said step of producing a polyphase moving magnetic field comprises producing a polyphase substantially linearly travelling magnetic field.

5. The method as set forth in claim 1, wherein said step of producing a polyphase moving magnetic field comprises producing a polyphase rotating magnetic field.

6. The method as set forth in claim 2, further including the step of rectifying said phase output of said second polyphase winding.

7. The method as set forth in claim 6, further including the step of combining said rectified phase outputs to produce a substantially DC power output.

8. The method as set forth in claim 6, wherein said step of magnetically coupling a second polyphase winding with said moving magnetic field comprises magnetically coupling said second polyphase winding with said moving magnetic field to produce a flat-topped polyphase power output including a flat-topped phase output for each of the phases of said second polyphase winding, wherein said step of rectifying said phase output comprises rectifying said flat-topped phase outputs and wherein said step of combining said rectified phase outputs comprises combining said rectified flat-topped phase outputs.

9. The method as set forth in claim 2, wherein said input power comprises DC input power and wherein said step of producing said polyphase moving magnetic field comprises the steps of:

connecting said DC input power to a switch connected to each of the phases of said first polyphase winding; and

closing and opening said switches in a controlled manner to produce a step-wise moving magnetic field.

10. The method as set forth in claim 9, further including means for synchronizing said closing and opening of said switches with said polyphase power output thereby allowing bilateral power conversion.

11. The method as set forth in claim 9, wherein said closing and opening of said switches do not occur simultaneously.

12. The method as set forth in claim 1, further including the step of adjustably shifting said first polyphase winding relative to said second winding to adjustably reduce said power output.

13. The method as set forth in claim 1, further including the step of adjustably shifting said first polyphase winding relative to said second winding to adjustably shift the phase of said power output.

14. A static electric power converter comprising a plurality of input windings, at least one output winding, and means for linking said input windings with said output winding by a moving magnetic field of substantially uniform magnitude, whereby said moving magnetic field induces an output voltage in said output winding as lines of flux of said moving magnetic field move through said output winding.

15. The static electric power converter as set forth in claim 14, wherein said input windings are wound on one of an inner core and an outer core and said output winding is wound on one of said inner core and outer core.

16. The static electric power converter as set forth in claim 15, wherein said inner core and said outer core is composed of a ferromagnetic material.

17. The static electric power converter as set forth in claim 15, wherein said input windings are wound on one of said outer core and inner core and said output winding is wound on the other.

18. The static electric power converter as set forth in claim 15, further including means for adjustably shifting said inner core rotatably relative to said outer core.

19. The static electric power converter as set forth in claim 15, further including means for adjustably shifting said inner core longitudinally relative to said outer core.

20. The static electric power converter as set forth in claim 14, further including a dummy core connected to an end of said inner core.

21. The static electric power converter as set forth in claim 14, wherein said input windings and said output winding are each wound on a noncylindrical base.

22. The static electric power converter as set forth in claim 21, further including means for adjustably shifting said input windings relative to said output winding in the direction of said moving magnetic field.

23. The static electric power converter as set forth in claim 21, further including means for adjustably shifting said input windings relative to said output winding in a direction perpendicular to the direction of said moving magnetic field.

24. The static electric power converter as set forth in claim 23, further including a dummy base connected to an end of one of said noncylindrical bases.

25. The static electric power converter as set forth in claim 21, wherein each of said noncylindrical is ferromagnetic.

26. The static electric power converter as set forth in claim 14, including a plurality of said output winding in which are induced phase output voltages.

27. The static electric power converter as set forth in claim 26, further including rectifier means connected to each of said output windings to produce substantially DC voltage from said phase output voltages.

28. The static electric power converter as set forth in claim 26, further including an electric switch connected to each of said input windings and a switch controller means for actuating said electric switch to produce stepped said moving magnetic field when DC input power is connected to said electric switches.

29. The static electric power converter as set forth in claim 28, further including means for detecting the phase of a polyphase power source connected to said output windings such that said switch controller means actuates said electric switches to produce said stepped moving magnetic field in synchronism with said polyphase power source.

30. A method for converting polyphase AC power to substantially DC power, comprising the steps of:

producing a polyphase magnetic field of a substantially constant flux density in a ferromagnetic material by means of a polyphase primary winding;

magnetically coupling a polyphase secondary winding with said magnetic field so as to produce a phase output for each of the phases of the polyphase secondary winding;

means for rectifying each said output phase to produce a rectified phase output; and

means for connecting said rectified phase outputs to a common terminal such that the output voltage between said output terminal and a neutral of said secondary winding comprises a rippled, substantially DC output voltage.

31. A method for converting polyphase AC power to substantially DC power, comprising the steps of:

producing a polyphase magnetic field in a ferromagnetic core by means of a polyphase primary winding;

magnetically coupling a polyphase secondary winding wound on a second ferromagnetic core with the magnetic field so as to produce a phase output for each of the phases of the polyphase secondary winding, the step of magnetically coupling comprising the step of fixedly positioning one of the cores inside of the other;

means for rectifying each said output phase to produce a rectified phase output; and

means for connecting said rectified phase outputs to a common terminal such that the output voltage between said output terminal and a neutral of said secondary winding comprises a rippled, substantially DC output voltage.

32. A polyphase power converter for converting polyphase AC power to substantially DC power comprising in combination:

a ferromagnetic outer core;

a ferromagnetic inner core;

means for fixedly positioning said inner core inside said outer core;

a primary winding wound on one of said outer core and inner core;

a secondary winding wound upon one of said outer core and inner core;

rectifier means connected to an output of each phase of said secondary winding; and

means for connecting the outputs of said rectifier to a common terminal such that the output voltage between said output terminal and a neutral of said secondary winding comprises a rippled, substantially DC output voltage when said polyphase primary winding is connected to the AC power source.

33. The converter as set forth in claim 32, wherein said polyphase primary winding is wound on one of said outer core and said inner core and said polyphase secondary winding is wound on the other said outer core and inner core.