The introduction of 800 VDC data centre power architecture marks a fundamental shift in how electricity is delivered to high-density AI computing systems.

As the power requirements of AI servers continue to rise, traditional low-voltage distribution architectures face growing challenges involving excessive current, heat loss, busbar size, cooling and usable rack space.

High-voltage direct current and solid-state transformer technologies offer a path towards more efficient and scalable AI data centres.

HVDC: Enabling high-density AI computing

Traditional server infrastructure has commonly used approximately 50 VDC to distribute power to IT equipment. At the power levels required by modern AI servers, however, maintaining this voltage can result in extremely high busbar currents.

Higher current creates several challenges:

• Greater electrical transmission losses
• Increased heat generation
• Larger and heavier busbars
• Additional cooling requirements
• Reduced space for computing equipment
• Greater complexity at rack and facility level

HVDC architectures using ±400 VDC or 800 VDC significantly reduce the current required to deliver the same amount of power. This improves transmission efficiency and enables electricity to reach high-power GPU systems through a shorter and more direct conversion path.

The role of solid-state transformers

Solid-state transformers use advanced power-semiconductor switching to perform efficient AC-to-DC conversion.

An SST can convert medium-voltage grid power, such as 13.8 kVAC, directly into an 800 VDC supply for AI server racks. Compared with conventional transformer and conversion architectures, SSTs can provide:

• Higher power-conversion efficiency
• Smaller equipment footprint
• Reduced use of copper and iron
• Modular and scalable system design
• Direct integration with HVDC infrastructure

According to Chroma’s article, direct HVDC delivery through SST technology can improve overall energy efficiency by more than 5%. At megawatt- or gigawatt-scale AI facilities, even a small improvement in efficiency can produce substantial reductions in energy use, cooling demand and operating costs.

High-power HVDC validation

As cloud service providers and AI infrastructure developers move towards ±400 V and 800 VDC architectures, reliable power testing becomes essential.

Rapidly changing AI workloads can produce sudden power surges. Test platforms must therefore reproduce both the power source and server-rack load while verifying system behaviour during dynamic operating conditions.

Chroma developed the 62450D-2000HL Programmable Bidirectional DC Power Supply for high-voltage, high-power testing. Its bidirectional design allows it to perform two roles:

Source mode

The 62450D-2000HL supplies high-voltage DC power to simulate the HVDC source. This enables engineers to validate the performance, stability and protection functions of power racks, power shelves and DC-to-DC conversion equipment.

Regenerative load mode

The same unit can accept DC power and emulate a high-power server-rack load. The absorbed energy is returned to the electrical grid rather than converted into waste heat.

Scalable testing up to 1.8 MW

Each 62450D-2000HL delivers up to 2,000 V and 45 kW in a compact 4U chassis. Multiple units can be configured in parallel to provide up to 360 kW within a standard 41U rack and up to 1.8 MW across multiple racks.

This scalable architecture supports testing for:

• ±400 V and 800 VDC power distribution
• HVDC power racks and sidecar systems
• Solid-state transformer modules
• Server power shelves and rack power systems
• AC-to-DC and DC-to-DC power converters
• Battery backup units and bidirectional converters
• Reliability, endurance and burn-in testing

High and low operating ranges

The 62450D-2000HL incorporates a dual-range design to address different HVDC test conditions.

Its high-voltage range supports operation up to 2,000 V, while its lower-voltage range provides higher current capability for applications such as ±400 V architectures. This allows one platform to address both high-voltage and high-current validation requirements.

Energy-efficient regenerative testing

During load operation, the 62450D-2000HL can return energy to the grid with efficiency of up to 94%.

Regenerative testing provides several advantages:

• Lower electricity consumption
• Reduced heat generation
• Lower laboratory cooling demand
• Reduced operating costs
• More sustainable long-duration testing
• Easier implementation of megawatt-scale validation

This is particularly valuable for reliability and burn-in tests that must operate continuously for extended periods.

Powering the future of AI infrastructure

Chroma’s high-voltage, bidirectional test platform enables developers to reproduce real-world HVDC conditions and validate power-conversion equipment before deployment.

By combining high voltage, megawatt-level scalability, source and load operation, fast transient response and regenerative energy recovery, the system supports the development of reliable and efficient power infrastructure for the 800 VDC AI era.

Meet Quantel at Data Centre World Asia 2026

Discover Chroma’s HVDC, AI server power, power shelf, rack power, BBU and automated test solutions at Quantel’s booth during Data Centre World Asia 2026.

Data Centre World Asia
29–30 September 2026
Sands Expo & Convention Centre, Singapore
Quantel Pte Ltd – Booth D54

Read the original Chroma ATE article:
https://www.chromaate.com/en/newsroom/news1083

Learn more about the Chroma 62450D-2000HL and 62000D Series:
https://www.chromaate.com/en/product/bidirectional_dc_power_supply_62000d_series_164