High-frequency transformers using solid wire for welding-type power supplies

A welding-type power supply, comprising:

• a switched mode power supply circuit configured to convert input power at a first voltage and a first frequency to a second voltage and a second frequency;
• and
• a high-frequency transformer configured to convert the second voltage at the second frequency to an output current, the high-frequency transformer comprising:
• a first coil assembly comprising a first plurality of turns of a first solid wire wrapped around a first bobbin to form a first single-layer primary winding, and a second plurality of turns of a first conductor over the first plurality of turns to form a first single-layer secondary winding;
• a second coil assembly comprising a third plurality of turns of a second solid wire wrapped around a second bobbin to form a second single-layer primary winding, and a fourth plurality of turns of a second conductor over the third plurality of turns to form a second single-layer secondary winding, wherein:
• the first single-layer primary winding is coupled in parallel with the second single-layer primary winding,
• the first conductor and the second conductor each comprise at least one of an obround cross-section, a rectangular cross-section, or a rectangular cross-section having radiused corners,
• the first conductor comprises a first end, a second end, and a first length extending between the first end and the second end,
• the first length of the first conductor comprises a first turned portion extending over the first plurality of turns of the first solid wire and defining the second plurality of turns of the second conductor, a first end portion extending from the first end to the first turned portion, and a second end portion extending from the first turned portion to the second end,
• the second conductor comprises a third end, a fourth end, and a second length extending between the third end and the fourth end,
• the second length of the second conductor comprises a second turned portion extending over the third plurality of turns of the second solid wire and defining the fourth plurality of turns of the second conductor, a third end portion extending from the third end to the second turned portion, and a fourth end portion extending from the second turned portion to the fourth end,
• the first length of the first conductor has a cross-section of the first conductor that is constant along at least the first turned portion of the first length of the first conductor,
• the second length of the second conductor has a cross-section of the second conductor that is constant along at least the second turned portion of the second length of the second conductor,
• the cross-section of the first conductor at a given point along at least the first turned portion of the first conductor is transverse to a direction of winding of the first conductor at that point, and
• the cross-section of the second conductor at a given point along at least the second turned portion of the second conductor is transverse to a direction of winding of the second conductor at that point;
• and
• first and second cores disposed at least partially within the first and second bobbins.

A welding-type power supply transformer, comprising:

• a first coil assembly comprising a first plurality of turns of a first solid wire wrapped around a first bobbin to form a first single-layer primary winding, and a second plurality of turns of a first conductor over the first plurality of turns to form a first single-layer secondary winding;
• a second coil assembly comprising a third plurality of turns of a second solid wire wrapped around a second bobbin to form a second single-layer primary winding, and a fourth plurality of turns of a second conductor over the third plurality of turns to form a second single-layer secondary winding, wherein:
• the first single-layer primary winding is coupled in parallel with the second single-layer primary winding to form a multi-core primary winding the first conductor and the second conductor each comprise at least one of an obround cross-section, a rectangular cross-section, or a rectangular cross-section having radiused corners, the first conductor comprises a first end, a second end, and a first length extending between the first end and the second end, the first length of the first conductor comprises a first turned portion extending over the first plurality of turns of the first solid wire and defining the second plurality of turns of the second conductor, a first end portion extending from the first end to the first turned portion, and a second end portion extending from the first turned portion to the second end, the second conductor comprises a third end, a fourth end, and a second length extending between the third end and the fourth end, the second length of the second conductor comprises a second turned portion extending over the third plurality of turns of the second solid wire and defining the fourth plurality of turns of the second conductor, a third end portion extending from the third end to the second turned portion, and a fourth end portion extending from the second turned portion to the fourth end, the first length of the first conductor has a cross-section of the first conductor that is constant along at least the first turned portion of the first length of the first conductor, and the second length of the second conductor has a cross-section of the second conductor that is constant along at least the second turned portion of the second length of the second conductor the cross-section of the first conductor at a given point along at least the first turned portion of the first conductor is transverse to a direction of winding of the first conductor at that point, and the cross-section of the second conductor at a given point along at least the second turned portion of the second conductor is transverse to a direction of winding of the second conductor at that point.