800VDC VS 480VAC AI Data Center Power

Introduction
AI computing racks keep rising to 80kW, 120kW and even MW-level power density. Data center operators are evaluating two mainstream power distribution routes: traditional 480VAC UPS and emerging 800VDC HVDC. The architecture choice directly affects PUE, CAPEX, OPEX and long-term scalability.
480VAC UPS Solution
• Advantages
1.Mature global supply chain for UPS, distribution cabinets and PDUs
2.Well-known operation and maintenance workflow for field teams
3.Proven reliability for medium-density and legacy IDC retrofits
• Limitations
1.Multiple power conversion stages: UPS rectification + inversion + secondary rectification by server PSU → higher energy loss
2.Larger current under the same power, requiring thicker cables and busbars, raising copper cost and line heat loss
3.The inverter is a typical single point of failure; slow response to sharp, fluctuating AI GPU loads
800VDC HVDC Solution
• Advantages
1.Simplified power chain: remove UPS inversion stage to lift end-to-end efficiency
2.Higher voltage reduces current significantly, cutting copper consumption and wiring space
3.Batteries connect directly to DC bus; no extra inversion during grid outage, higher backup reliability
4.Microsecond-level dynamic response, perfectly matching sudden power spikes of AI workloads
5.Native compatibility with PV and energy storage, easier to build low-carbon green computing infrastructure
Considerations
Still in the growth stage; supporting standards and 800V server ecosystem are continuously improving
Tonhe 800V HVDC System for AI Data Centers
Tonhe is an early participant in compiling the 800V DC Power Supply Technical Whitepaper for Data Centers, with mature HVDC technology for AIDC deployment.
• Core module: self-developed TH750H40NZ-A, 30kW per module, peak efficiency over 98%
• Adopts SiC soft-switching topology, double-sided potting for ruggedization; supports -40℃ cold start and hot swap
• Compatible with air cooling and liquid cooling; max system capacity up to 1MW, supports N+1 / N+X redundancy
• Full system scope: rectifier cabinet + DC distribution cabinet + intelligent monitoring unit
• Multi-protocol monitoring: real-time data collection, fast fault location, seamless docking with BMS and O&M platforms
• Compatible with Tonhe’s existing 240V / 336V HVDC portfolio, supporting phased, smooth migration
• Suitable for newly built high-density AIDC and liquid-cooled computing parks, available for both domestic and overseas projects
Conclusion
480VAC remains a stable, low-risk option for legacy facilities and moderate-density racks.
800VDC HVDC is the forward-looking power architecture designed for high-power AI clusters. Tonhe’s 800V HVDC platform reduces conversion losses and distribution infrastructure investment, while reserving sufficient expansion space for future green computing upgrades.