The stacking of transformer cores is a critical process in transformer manufacturing, significantly affecting its electrical performance and operational efficiency. Below are the main requirements for transformer core stacking:
1. Material Requirements
Silicon Steel Sheets: High magnetic permeability and low-loss silicon steel sheets must be used, with flat and undamaged surfaces.
Insulation Coating: The insulation coating on the silicon steel sheets must remain intact to prevent interlayer short circuits.
2. Stacking Method
No Air Gaps: The core sheets should be tightly stacked to minimize air gaps, reducing magnetic circuit resistance and noise.
Staggered Stacking: Core joints should be stacked in a staggered manner (typically 45° or 90°) to reduce magnetic flux leakage.
Neat Ends: The ends of the core should be uniformly aligned to prevent uneven electromagnetic fields.
3. Process Requirements
Stacking Sequence: Sheets should be stacked in a predetermined order to avoid dimensional confusion.
Avoid Scratches: The stacking process must avoid scratching the surface of the silicon steel sheets, which could compromise insulation performance.
Securing and Binding: After stacking, the core should be secured with bindings or clamps to ensure overall stability.
4. Electromagnetic Performance Requirements
Low Loss: Minimize eddy current losses and hysteresis losses in the core.
Reduced Noise: Tightly stacked cores produce less operational noise.
High Magnetic Permeability: Ensure efficient magnetic flux transfer under rated working conditions.
5. Inspection Requirements
Appearance Check: Ensure the core surface is smooth and free from scratches, and the joints are tightly fitted.
Dimensional Accuracy: The dimensions of the core must meet design specifications to avoid assembly issues.
Insulation Performance Test: The insulation coating of the silicon steel sheets must pass voltage withstand testing.
Proper transformer core stacking significantly improves performance, extends service life, and reduces operational losses and noise.
