Optimized Multilayer PCB Litz Windings for Uniform Current Distribution and Reduced Loss

PCB Litz wire is a promising method to solve the high eddy loss issue in PCB windings. However, it suffers from high DC conduction loss due to the existing 2-layer integration style and poor flexibility. This paper firstly proposes a way to minimize the twists, reducing the DCR by 31% with the same AC related loss. Furthermore, a multi-layer PCB Litz integration is proposed to realize uniform current sharing in 4 or more layers. When implementing 3 turns in 12 layers, the proposed design has at least 43% lower ACR than other capacity enhancing configurations at 200kHz. With the improvements, the flexibility is also increased, with any turns can be made in any even number of layers. The new configuration makes PCB Litz wire competitive with traditional Litz wire, especially in high-power applications.