Multi-wire Lay Winding

Introduction to Multi-Wire Stacked Winding

Multi-wire stacked winding is a coil manufacturing method where multiple insulated conductors (typically two or more) are wound simultaneously or in layers onto a form. Its core principle involves optimizing the coil's current-carrying capacity, heat dissipation, and electromagnetic performance through coordinated conductor arrangement, making it suitable for high-current, low-loss applications.

I. Fundamental Winding Methods and Key Points

Conductor Selection and Pre-processing: Primarily employs enameled copper wires of identical gauge and material (alternatively, different gauges may be combined as required). Prior to winding, multiple conductors must be aligned parallel to ensure consistent tension, preventing conductor misalignment or uneven tightness during winding.

Winding Process: Utilize multi-axis synchronous winding machines to simultaneously wind multiple wires onto the core, forming a “single-layer, multi-wire parallel” structure. For increased turns, employ “multi-layer stacked winding.” Insert insulating paper between layers to prevent interlayer short circuits. Maintain orderly wire arrangement during each layer to minimize gaps.

End Processing: After winding completion, the ends of multiple wires are consolidated. After stripping the end insulation, they are uniformly crimped or welded to ensure even current distribution among the wires.

II. Core Features

High Current Carrying Capacity: Parallel conduction of multiple conductors effectively increases the equivalent conductor cross-sectional area. Compared to single-conductor coils, this design supports higher currents while distributing load evenly across wires, preventing localized overheating.

High Heat Dissipation Efficiency:

Minimal gaps between wires create natural cooling channels. The increased total surface area facilitates heat dissipation, reducing performance degradation caused by coil overheating.

Reduced Skin Effect Impact:

In high-frequency applications, single wires experience increased resistance and losses due to the skin effect (current concentration near the surface). Stacking multiple fine wires reduces individual wire diameter, weakens the skin effect, and lowers high-frequency losses.

III. Primary Applications

Power Equipment: Windings in large transformers and reactors requiring high current capacity. Multi-wire stacking meets current demands while ensuring safe operation through layered insulation.

Industrial Motors: Used in stator and rotor windings of high-power motors, enhancing current-carrying capacity and heat dissipation to ensure long-term high-load operation.

High-Frequency Electronic Equipment: Such as coils in RF generators and high-frequency induction heating devices. Layered winding reduces high-frequency losses, ensuring efficiency and stability under high-frequency conditions.

IV. Differences from Single-Wire Winding

Performance Focus: Single-wire winding offers simplicity and low cost, suitable for low-current, low-power applications. Multi-wire layered winding prioritizes high current and low loss, requiring specialized equipment and insulation treatment at a slightly higher cost.

Winding Difficulty Differences: Single-wire winding requires no synchronized tension control for multiple conductors, making operation straightforward. Multi-wire layered winding demands precise conductor synchronization and orderly arrangement, imposing higher demands on equipment accuracy and process control.