System and method for orthogonal inductance variation

• US 6,674,320 B2
• Filed: 10/16/2001
• Issued: 01/06/2004
• Est. Priority Date: 10/16/2000
• Status: Active Grant

• Current Assignee: Infineon Technologies Austria Ag (Infineon Technologies AG)
• Original Assignee: Primarion Incorporated (Infineon Technologies AG)
• Inventors: Zhang, Yi, Trivedi, Malay, Duffy, Thomas P.
• Primary Examiner(s): Riley, Shawn
• Application Number:
  US09/978,613
• Publication Number:
  US 20020060621A1
• Time in Patent Office: 812 Days
• Field of Search: 327/552, 327/553, 327/555, 327/557, 327/110, 327/445, 327/453, 336/40, 336/155, 336/160, 336/165
• US Class Current: 327/555
• CPC Class Codes: H01F 29/14 with variable magnetic bias amplitude modulation by means of variable impedance element H03C1/08 ; magnetic amplifiers H03F; circuits for automatic telephonic communication H04M3/00

Abstract

A control system, method and apparatus is provided for an orthogonally variable inductor. A method and apparatus is also provided for voltage regulation. Regulation is provided without the use of Silicon devices, such as FET'"'"'s, in the output current path. Efficient voltage regulation is provided via varying the inductance of a device in the output current path, and alternatively via varying the inductance and duty cycle. An orthogonal inductive device is provided to vary the inductance in the output current path. The orthogonal inductive device is an external H field device, a series method orthogonal flux device, or a combined core device. Furthermore, a variable inductor is also provided in filters, amplifiers, and oscillators.

Claims

1. A variable inductor comprising:

a gating winding;

a magnetic core;

an inductor winding in communication with the magnetic core and configured to generate core magnetic field lines when current flows though the inductor winding;

a gating core configured to generate gating magnetic field lines orthogonal to and intersecting with the core magnetic field lines when a current flows though the gating winding; and

a gating source for providing the current to the gating winding;

wherein the variable inductor is further configured to provide stepping between a range of discrete operating frequencies.

2. The variable inductor of claim 1, further comprising a controller configured to cause the gating source to control the current to the gating winding.

3. The variable inductor of claim 1, further comprising a controller configured to provide at least two levels of current in the gating winding.

4. The variable inductor of claim 1, wherein the gating source is configured to provide at least two levels of current in the gating winding, and is configured to create more than one inductance value.

5. The variable inductor of claim 1, the variable inductor further configured to vary inductance of the inductor over a range of inductance values.

6. The variable inductor of claim 1 further configured to provide a fine adjustment over an operating frequency range.

7. A rectifier circuit comprising the variable inductor of claim 1.

8. An amplifier circuit comprising the variable inductor of claim 1.

9. An oscillator circuit comprising the variable inductor of claim 1.

10. A method for efficient voltage regulation, the method comprising the steps of:

magnetically influencing a magnetic path of an output inductor;

wherein the magnetic influence creates a first effective inductance in the output inductor during a first time period;

changing the magnetic influence of the magnetic path of the output inductor to create a second effective inductance in the output inductor during a second time period; and

controlling a directional inductive device with a controller, wherein the directional inductive device is configured to vary the inductance of the output inductor;

wherein the directional inductive device is configured with a gating source, a gating winding, a gating core, an output inductor winding, and an inductor core; and

wherein the gating core is configured to control the presence of magnetic field lines in relation to a plurality of field lines in the output inductor core by varying the effective gap length in the inductor core.

11. The method of claim 10, wherein the first time period represents a time period when a transformer secondary winding provides a positive voltage.

12. The method of claim 11, the second time period represents a time period when a transformer secondary winding provides a negative voltage.

13. The method of claim 10, wherein the directional inductive device is configured to vary the inductance in a combined core by varying a gating current in a gating winding.

14. The method of claim 10, wherein the directional inductive device is configured to vary the inductance in a combined core by varying a volt-second product applied to the gating winding.

15. A method for providing voltage regulation comprising the steps of:

providing a first control signal from an inductance controller to an orthogonal inductive device configured to create a first inductance in an output inductor during a time period Ton;

providing a second control signal from an inductance controller to an orthogonal inductive device configured to create a second inductance in the output inductor during a time period Toff; and

varying at least one of the first inductance and second inductance to regulate a voltage output;

wherein the varying step further comprises the step of varying an effective gap length of an inductor core.

16. The method of claim 15 further comprising the step of varying a duty cycle to regulate the voltage output.

17. The method of claim 15 further comprising the step of varying a phase relationship of the inductance change to the ON and OFF times to regulate a voltage output.

18. A voltage regulation system comprising:

a controller configured to vary the inductance of an output inductor;

an orthogonal inductive device configured to vary the inductance of the output inductor as directed by the controller;

an AC power source in communication with a power transformer;

the power transformer being configured in communication with the orthogonal inductive device; and

an output load in communication with the orthogonal inductive device, wherein the voltage regulation system is further configured to vary an effective gap length of an inductor core.

19. The voltage regulation system of claim 18 further configured to varying the inductance of the output inductor to generate at least a first inductance and a second inductance;

wherein the first and second inductances are configured to regulate a voltage output.

20. The voltage regulation system of claim 18 further configured to vary a duty cycle to regulate the voltage output.

21. The voltage regulation system of claim 18 further configured to vary a phase relationship of the inductance change to the ON and OFF times to regulate a voltage output.

22. The voltage regulation system of claim 18 the orthogonal inductive device further comprising an output inductor.