Custom 3‑phase Planar Transformer for High‑Density Data Center Power
As server racks, telecom rectifiers, and AI power shelves scale above 6 kW, designers face intense pressure on efficiency, heat dissipation, and size. A 3‑phase LLC topology paired with advanced planar magnetics provides an effective path forward, enabling compact, high‑power solutions.
Payton Planar Magnetics has developed a custom 3‑phase planar transformer specifically for high‑density power bricks. Using a three‑limb core structure, it achieves partial flux cancellation between phases, which shrinks the overall magnetic footprint and balances heat distribution. The result is superior thermal management, reduced EMI, and more power in less space.
Advantages of 3‑Phase LLC Over Single‑Phase Designs
This architecture delivers clear benefits for high‑power applications. Lower RMS currents per phase allow smaller conductors and fewer losses, while reduced magnetic volumes support greater power density. Thermal symmetry across phases simplifies cooling, and natural ripple cancellation improves overall system efficiency, EMI control, and the ability to use moderately lower switching frequencies without size penalties.
Technical Specifications
The transformer is rated for a 6 kW power stage, providing 3‑phase output at 280 VDC and 7.5 A. It operates at switching frequencies of 250-350 kHz, with a peak input voltage range of 405-420 V using bipolar waveforms and primary currents up to 8.5 Arms (12 A peak).
Each phase features a 3:2 turns ratio, with a total height of just 25 mm and dielectric strength up to 4250 VDC. These specs make it ideal for size‑constrained, thermally demanding environments.
Key Specifications
- Power stage: 6 kW (3‑phase, 280 VDC / 7.5 A)
- Frequency: 250-350 kHz
- Input voltage: 405-420 V peak (bipolar)
- Primary current: 8.5 Arms max (12 A peak)
- Turns ratio: 3:2 per phase
- Height: 25 mm
- Dielectric strength: 4250 VDC
Payton offers 100% custom planar magnetics to fit your data center or AI power requirements.