Currently, no high-frequency transformers in China are made with flat copper strips. If flat copper strips were used, they would need to be made extremely flat, which is very difficult in terms of manufacturing processes; otherwise, the eddy current losses in the conductor would be very high at high frequencies. Currently, high-frequency transformers primarily use Litz wire to avoid eddy current losses at high frequencies.
Determine whether to use Litz wire or copper tape by comparing the size of the magnetic core with the magnitude of the current. Use Litz wire for low currents and copper tape for high currents.
The advantage of Litz wire is that it is simpler to manufacture than copper strip; the disadvantage is that if the current is too large, too many strands of Litz wire are needed, and the manufacturing cost may be higher than that of copper strip.
Designing copper strips is similar to designing Litz wire. First, determine the current rating. Based on the temperature rise requirements, determine the current density. Divide the current by the current density to get the required cross-sectional area. Then, calculate the required wire size based on the cross-sectional area. The difference is that the cross-sectional area of Litz wire is the sum of multiple circles, while that of copper strip is rectangular.
copper strip relative to Lids wire
Advantages: Ideal for use in one or two-turn windings, high space utilization, low leakage inductance, and high current tolerance.
Disadvantages: High cost, unsuitable for high-revolution counts, poor versatility, and complex manufacturing process.
Calculation: Length multiplied by height equals the area, which is equivalent to the sum of the cross-sectional areas of all Leeds lines.
Flat copper strips cannot be used at high frequencies because the skin effect becomes more pronounced at such high frequencies, and winding them is very inconvenient. Their advantage lies in their suitability for high currents. Litz wire, on the other hand, is the opposite. It has advantages at high frequencies and is easy to wind. However, it is prone to overload at high currents.
