Inductor assemblies and methods for forming the same

A method for forming a dual coil inductor assembly, the method comprising:

• providing a first metal foil, a first electrical insulator sheet, a second metal foil, and a second electrical insulator sheet;
• and
• spirally co-winding the first metal foil, the first electrical insulator sheet, the second metal foil, and the second electrical insulator sheet to form a combined coil in which:
• the spirally wound first metal foil forms a first coil;
• the spirally wound second metal foil forms a second coil;
• and
• the first and second electrical insulator sheets are interposed between the first and second metal foils so that the first and second metal foils are electrically insulated from one another by the first and second electrical insulator sheets;
• electrically connecting a first terminal to the first metal foil at a first location;
• electrically connecting a second terminal to the first metal foil at a second location spaced apart from the first location along the first metal foil;
• electrically connecting a third terminal to the second metal foil at a third location;
• and
• electrically connecting a fourth terminal to the second metal foil at a fourth location spaced apart from the third location along the second metal foil.

A method for using a dual coil inductor assembly, the method comprising:

• providing a dual coil inductor assembly including:
• a coil assembly including:
• a first metal foil having opposed first and second ends;
• a first electrical insulator sheet;
• a second metal foil having opposed first and second ends;
• a second electrical insulator sheet;
• and
• first, second, third and fourth terminals;
• wherein:
• the first metal foil, the first electrical insulator sheet, the second metal foil, and the second electrical insulator sheet are all spirally co-wound to form a combined coil;
• the spirally wound first metal foil forms a first coil;
• the spirally wound second metal foil forms a second coil;
• and
• the first and second electrical insulator sheets are interposed between the first and second metal foils so that the first and second metal foils are electrically insulated from one another by the first and second electrical insulator sheets;
• the first terminal is electrically connected to the first metal foil at a first location, the second terminal is electrically connected to the first metal foil at a second location, and the first and second locations are spaced apart along the first metal foil;
• and
• the third terminal is electrically connected to the first metal foil at a third location, the fourth terminal is electrically connected to the second metal foil at a fourth location, and the third and fourth locations are spaced apart along the second metal foil;
• connecting the dual coil inductor assembly to first and second lines of an AC electrical system, including:
• electrically connecting an input of the first line to the first terminal;
• electrically connecting an output of the first line to the second terminal;
• electrically connecting an input of the second line to the third terminal;
• and
• electrically connecting an output of the second line to the fourth.

A dual coil inductor assembly comprising:

• an inner coil assembly including:
• an inner coil including:
• an inner metal foil;
• and
• an inner electrical insulator sheet spirally co-wound with the inner metal foil;
• and
• first and second terminals;
• an outer coil assembly including:
• an outer coil including:
• an outer metal foil;
• and
• an outer electrical insulator sheet spirally co-wound with the outer metal foil;
• and
• third and fourth terminals;
• wherein:
• the outer coil defines an outer coil air core;
• the inner coil is disposed within the outer coil air core so that the outer coil circumferentially surrounds the inner coil;
• the first terminal is electrically connected to the inner metal foil at a first location, the second terminal is electrically connected to the inner metal foil at a second location, and the first and second locations are spaced apart along the inner metal foil;
• and
• the third terminal is electrically connected to the outer metal foil at a third location, the fourth terminal is electrically connected to the outer metal foil at a fourth location, and the third and fourth locations are spaced apart along the outer metal foil.

A method for using a dual coil inductor assembly, the method comprising:

• providing a dual coil inductor assembly including:
• an inner coil assembly including:
• an inner coil including:
• an inner metal foil;
• and
• an inner electrical insulator sheet spirally co-wound with the inner metal foil;
• and
• first and second terminals;
• an outer coil assembly including:
• an outer coil including:
• an outer metal foil;
• and
• an outer electrical insulator sheet spirally co-wound with the outer metal foil;
• and
• third and fourth terminals;
• wherein:
• the outer coil defines an outer coil air core;
• the inner coil is disposed within the outer coil air core so that the outer coil circumferentially surrounds the inner coil;
• the first terminal is electrically connected to the inner metal foil at a first location, the second terminal is electrically connected to the inner metal foil at a second location, and the first and second locations are spaced apart along the inner metal foil;
• and
• the third terminal is electrically connected to the outer metal foil at a third location, the fourth terminal is electrically connected to the outer metal foil at a fourth location, and the third and fourth locations are spaced apart along the outer metal foil;
• connecting the dual coil inductor assembly to first and second lines of an AC electrical system, including:
• electrically connecting an input of the first line to the first terminal;
• electrically connecting an output of the first line to the second terminal;
• electrically connecting an input of the second line to the third terminal;
• and
• electrically connecting an output of the second line to the fourth.