Abstract：In order to reduce the winding losses of magnetic components, Litz wires brought designers into sharp focus. But its large strands and complex twisting mode makes the winding loss of Litz wires difficult to calculate and simulate. This paper from twisting mode to analysis the current assignment characteristics of different twisting mode of Litz wires, and particularly analysis the concentric twisted Litz wires which is more widespread used in the industry. The thought is proposed that concentric twisted Litz wires can be approximately replaced by segmented stranded parallel wires, and the single wire current of concentric twisted Litz wires can be solved by using the segmented equivalent circuit method based on this thought. Reassignment the single wire current value to 2D stranded parallel wires model for simulation, and then the winding loss of concentric twisted Litz wires can be solved. Finally, it is proved that the segmented equivalent circuit method is effective and accurate for solving the concentric twisted Litz wire winding losses.
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