ABB’s HiPerGuard Medium-Voltage UPS Wins 2025 Data Center Power Innovation Award

ABB, a global technology company specializing in electrification and automation, is playing an increasingly visible role in addressing the power challenges created by the rapid growth of large-scale and AI-driven data centers. As these facilities evolve into “AI factories” with unprecedented power densities, operators are looking for new approaches to ensure resilient, efficient, and grid-aware electrical infrastructure.

ABB has addressed these needs by developing HiPerGuard, a medium voltage uninterruptible power supply (UPS) that shifts power protection upstream to the medium-voltage level and uses a ZISC (Impedance Isolated Static Converter) architecture to combine high efficiency with robust fault performance. HiPerGuard simplifies the electrical backbone of hyperscale and AI-focused sites, supporting high availability and reducing both energy use and infrastructure complexity.

This approach has earned ABB the Innovation award in the Data Center Power category of the 2025 Power Technology Excellence Awards.

Redefining data center electrical architecture with medium voltage UPS

HiPerGuard offers new electrical architecture for large-scale data centers by implementing UPS protection at medium voltage, with configurations at 5kV, 7.2 kV, 12 kV, 15 kV, and 24 kV. It shifts resilience closer to the grid connection point instead of relying on multiple low-voltage UPS units distributed across the data hall. This medium voltage, centralized approach alters the traditional topology of large data centers and high-density AI data center campuses.

Placing protection at higher voltage reduces current levels, which in turn lowers thermal losses and allows the use of smaller, less costly copper cabling.

A single medium-voltage UPS is capable of safeguarding an entire data center from a centralized location, eliminating the need for protection at the level of individual rooms or specific server rows.

This can significantly reduce the need for parallel low-voltage UPS systems, associated switchgear, transformers, and extensive cabling networks. As a result, the electrical infrastructure is simplified, the physical footprint of power equipment is reduced, and installation and maintenance activities can be streamlined.

For large AI data centers (sometimes referred to as AI factories), where power demands can exceed 100 MW per campus, this architecture supports scaling in substantial power blocks without a proportional increase in system complexity. In projects such as Applied Digital’s 400MW greenfield AI campus in North Dakota, HiPerGuard is used as the backbone of the electrical infrastructure, enabling the site to expand in 25MW increments while maintaining a consistent protection concept. This demonstrates how a medium-voltage UPS can serve as the backbone of large, high-density data center campuses.

Hybrid passive–active UPS design boosting data center power efficiency and fault performance

HiPerGuard uses a ZISC design that differs from conventional online double-conversion systems and rotary UPS technologies. At its core is an isolating line reactor on the input side, which acts as a barrier, preventing grid disturbances from reaching the load and improving the power factor seen from the grid side. This allows the system to provide continuous power conditioning at medium voltage without requiring the static converters to operate at full load under normal conditions.

In a conventional double-conversion UPS, AC power is constantly converted to DC and then back to AC, which inherently produces continuous conversion losses. In contrast, HiPerGuard’s passive reactor handles most routine disturbances, while the solid-state converters engage proportionally. They provide limited correction for minor issues and transition to full power operation only during severe events, such as a complete loss of utility power.

When utility supply is stable, power flows through the reactor to the load with minimal converter involvement; during an outage, the static converter draws on lithium-ion batteries and inverts stored DC energy to maintain supply to the data center.

This operating mode delivers a significant gain in efficiency. HiPerGuard achieves 98% efficiency at voltages up to 24 kV. Over a 15-year lifecycle, this efficiency level, together with the use of batteries in place of traditional rotary components and diesel generators for short-duration support, can lead to a reduction in harmful emissions. ABB indicates that a 1360-ton reduction in emissions is possible over such a period when compared with traditional rotary UPS systems. These improvements occur in a part of the power chain where losses are particularly impactful due to the continuous nature of UPS operation.

At the same time, the system maintains high power quality and protection performance. HiPerGuard delivers a clean output voltage in accordance with IEC 62040-3 Class 1, making it suitable for mission-critical compute loads. It can also provide up to five times nominal current for two seconds in power conditioning mode. This high short-duration current capability supports selective coordination of downstream protection and assists in rapid fault clearing in complex, high-density electrical networks typical of large data center campuses.

Improving data center availability, total cost, and readiness for grid services

HiPerGuard is designed to influence both availability and lifecycle economics in large data centers. By consolidating protection into high-power medium-voltage blocks, the overall number of UPS units, switchgear lineups, transformers, and low-voltage distribution components can be reduced. A lower equipment count and fewer interfaces help contain system complexity and can simplify maintenance planning.

The system’s modular converter arrangement contributes to resilience. HiPerGuard can tolerate the loss of up to three modules without an automatic transfer to bypass mode. This modularity reduces the likelihood that a single converter issue will expose the load to unprotected conditions. Combined with the centralized medium-voltage protection concept, this supports the levels of availability demanded by operators for whom even short periods of downtime can carry very high financial and operational impacts.

The economic implications are notable. Protecting power at medium voltage reduces current, allowing thinner conductors and lowering energy losses from heat, which can translate into reduced electricity costs. A medium-voltage UPS can replace multiple lower-voltage UPS systems, freeing up valuable white space that can be repurposed for IT racks rather than power equipment. These units can also be located in electrical rooms or substations, often on less expensive real estate away from critical IT areas. Because the infrastructure required around HiPerGuard is comparatively simpler, the inherent reliability of the overall system can be improved through fewer components and interconnections.

The system also contributes to grid reliability and flexibility. Large data centers typically incorporate substantial redundant capacity and battery systems, resulting in significant embedded energy storage that is not fully utilized during normal operation. The HiPerGuard medium-voltage UPS has the capability, in addition to its primary role of load protection, to inject power into or absorb power from the electrical network when requested by an external power plant controller if network stability is threatened. This enables the same infrastructure used for data center protection to be deployed, when appropriate, in support of grid stability needs such as demand management or frequency regulation.

HiPerGuard is already being deployed in large-scale data centers and research facilities in North America and Europe that require high energy efficiency, elevated power density, and robust grid interaction. ABB’s infrastructure partnership with Applied Digital in North Dakota and its collaboration with Nvidia on power solutions for future large-scale data centers show how this medium-voltage UPS platform is being integrated into major sites.

Company Profile

ABB is a global technology leader in electrification and automation, enabling a more sustainable and resource-efficient future. By connecting its engineering and digitalization expertise, ABB helps industries run at high performance while becoming more efficient, productive, and sustainable. With a history stretching back over 140 years and around 110,000 employees worldwide, ABB’s purpose is to help customers outperform while moving toward a low-carbon society. The company’s strategy is encapsulated in the phrase: ‘Engineered to Outrun.’