Data Center & AI Power · 30 VA–70 kVA
Toroidal Transformers for Data Centers & AI Power
High-efficiency toroidal transformers from 30 VA to 70 kVA (single-phase) and PowerTower configurations up to 150 kVA for modular UPS, PDUs, high-frequency conversion stages, and edge data centers.
Overview
Transformers for Modular, Rack-Level & Conversion-Stage Data Center Power
AI workloads are pushing rack densities toward the megawatt range and changing how power is converted and distributed inside the facility. Bridgeport builds the compact, high-efficiency magnetics that live in the modular, rack-level, and conversion stages — from 30 VA to 70 kVA single-phase (PowerTower configurations higher) — not the facility-main distribution transformers. Since 1982 we’ve built toroidal transformers for UPS systems, rack and row PDUs, battery energy storage, and the high-frequency conversion stages inside modern data-center power electronics.
The Challenge
Why Data Centers Need High-Efficiency Transformers
Data centers face constant pressure to improve energy efficiency while raising power density. Every watt lost in the power path becomes heat that cooling systems then have to remove, so transformer losses hit the facility twice — once at the transformer and again at the chiller. Toroidal transformers support both goals at once through lower core and no-load losses and a more compact form factor than equivalent E-I designs.
They also generate significantly less electromagnetic interference, which matters in a room packed with sensitive IT equipment, and their reduced heat output helps lower cooling demand — improving overall Power Usage Effectiveness (PUE). As facilities scale, these characteristics make toroidal designs an attractive option for power distribution and conversion equipment.
Most facility-scale distribution is handled by large dry-type transformers; the real opportunity for compact toroidal magnetics is at the modular, rack, and high-frequency stages, where size, EMI, and continuous-duty efficiency matter most.
Key Advantages
What Toroidal Transformers Bring to the Data Center
Four properties matter most in dense, power-constrained facilities — and toroidal construction delivers all of them. Ideal for continuous-duty modular and rack environments where every watt of loss and every dB of EMI counts.
Higher Efficiency
Typically 98–99% versus 94–97% for traditional E-I designs. Lower no-load and core losses cut energy cost and reduce the heat cooling systems must remove.
Very Low EMI
The closed toroidal core keeps stray magnetic fields to a minimum — protecting sensitive monitoring, control, and IT equipment nearby.
High Power Density
40–50% smaller and lighter than equivalent E-I transformers, freeing rack and floor space in facilities where liquid cooling already occupies room.
Better Thermal Performance
More even heat distribution and cooler operation improve reliability in continuous-duty, space-constrained installations.
Quieter Operation
Lower audible noise than laminated designs — an advantage in occupied colocation and edge environments.
Custom-Engineered
Built to exact voltage, current, size, and thermal specs so OEMs and operators design without compromise.
The 800 VDC Shift
800 VDC, Solid-State Transformers & High-Frequency Magnetics
Facility-level medium-voltage conversion is typically handled by solid-state or large conventional transformers; Bridgeport toroids excel in the high-frequency magnetics and supporting AC isolation stages within these architectures. AI data centers are moving toward 800 VDC distribution to support extreme rack densities, cut conversion losses, integrate renewables, and buffer the grid against sudden AI load swings. Paired with DC-coupled battery storage, these architectures remove conversion stages and smooth large power fluctuations. Industry projections point to up to 5% better end-to-end efficiency, up to 70% lower maintenance, and significantly reduced copper.
This does not eliminate the transformer — it raises the bar. Inside solid-state transformers and the high-ratio DC-DC converters that step 800 VDC down to server voltages, toroidal cores excel at high switching frequencies: low core loss, strong power density, and excellent EMI performance — exactly what dense, high-power racks demand.
- Medium-voltage AC to 800 VDC — solid-state conversion at the facility edge with fast response.
- DC-coupled BESS — fewer conversion stages, lower losses, smoother AI load profiles.
- High-frequency magnetics — toroidal cores hold low losses where laminated designs fall off.
- Hybrid reality — most facilities run AC and DC side by side for years, keeping demand for both.
- Support loads stay AC — cooling, liquid-cooling infrastructure, and lighting still need clean, isolated AC power.
Construction
Toroidal vs. Traditional E-I Transformers
Why data-center, BESS, and mission-critical OEMs are moving away from standard E-I designs toward custom toroidal solutions. These advantages are most valuable in the 0–70 kVA class used in modular and rack systems.
Energy Storage
Battery Energy Storage & On-Site Power
Battery energy storage systems (BESS) are central to how AI data centers ride through load swings and firm up on-site power. BESS transformers must stay efficient across frequent charge and discharge cycles while managing heat in compact, increasingly containerized installations.
Toroidal designs deliver higher efficiency and lower core losses — improving the system's round-trip efficiency — while their compact size supports the higher power density modular BESS demands. Lower EMI protects the surrounding power electronics and control systems. Bridgeport's PowerTower platform integrates high-efficiency magnetics for BESS and data-center power.
Applications
Where Bridgeport Transformers Fit in the Data Center
Modular & Rack-Level UPS Isolation
Clean, isolated power for modular and rack-level UPS, with lower no-load and continuous-duty losses that cut heat and cooling load.
High-Frequency Conversion Magnetics
High-frequency toroidal cores for solid-state and DC-DC conversion stages in 48 V and 800 VDC architectures.
See PowerTower →Rack & Row PDU Isolation / Step-Down
Compact, low-EMI toroidal transformers for rack- and row-level PDU isolation and step-down where space is tight.
EMI/RFI Filter Inductors & Common-Mode Chokes
Filter inductors and common-mode chokes for clean-power zones, conversion stages, and noise-sensitive IT environments.
EMI filters & chokes →Edge, Modular & Containerized Power
Compact magnetics for edge, modular, and containerized data centers, where footprint, continuous-duty efficiency, and low EMI are all at a premium.
Compact BESS Module-Level Magnetics
Module-level transformers and magnetics for DC-coupled, containerized battery energy storage — efficient across frequent charge/discharge cycles with low EMI.
Branch-Circuit Current Transformers
Compact toroidal current transformers for power-quality and branch-circuit monitoring.
Metering CTs →Support-System Isolation
Reliable isolated AC power for cooling and liquid-cooling infrastructure, controls, and clean-power zones that support the IT load.
Why Bridgeport
Why Choose Bridgeport Magnetics for Data-Center Power
Toroidal specialists since 1982
Specialists in high-efficiency toroidal magnetics from 30 VA to 70 kVA (PowerTower configurations higher), with proven low-EMI performance for data-center and AI power electronics.
Efficiency where it counts
98–99% efficient designs that cut both energy cost and downstream cooling load.
Made in the USA
Engineered, wound, and tested in Shelton, Connecticut — Buy-American eligible.
Custom & high-frequency capable
From 30 VA–70 kVA single-phase 60 Hz UPS and PDU units to high-frequency cores for solid-state conversion — plus EMI filter inductors and common-mode chokes, all built to spec.
Individually tested
Serial-marked with test reports stored electronically and available on request.
Direct engineering support
Talk to the people who design and build your transformer.
FAQ
Frequently Asked Questions
Data centers use transformers throughout the power path — in UPS systems, power distribution units (PDUs), and increasingly in the high-frequency conversion stages of modern power electronics. High-efficiency toroidal transformers are favored for these roles because they deliver lower losses, very low EMI, and a compact footprint in space-constrained facilities. Bridgeport supplies these modular, rack-level, and conversion-stage magnetics — not the large facility-main distribution transformers.
They provide higher efficiency (typically 98–99%), lower electromagnetic interference, and a 40–50% smaller footprint than equivalent E-I designs — advantages that matter most in the space-constrained, continuous-duty modular UPS, rack PDU, and high-frequency conversion layers where Bridgeport toroids are used. Lower losses also mean less heat for cooling systems to remove, supporting higher power density and better Power Usage Effectiveness (PUE).
800 VDC is an emerging data-center architecture in which facility-level solid-state or conventional transformers convert medium-voltage grid AC to regulated 800 VDC, cutting conversion stages and losses. It does not eliminate transformers — it raises requirements. Bridgeport's role is inside these architectures: the high-frequency toroidal cores used in solid-state transformers and 800 VDC DC-DC converters, plus the supporting AC isolation stages, where low loss, high power density, and low EMI matter most.
Yes. Battery energy storage systems need transformers that stay efficient across frequent charge and discharge cycles while managing heat in compact, containerized installations. Toroidal designs offer higher round-trip efficiency, higher power density, and lower EMI — a strong fit for DC-coupled BESS and on-site power.
Every watt lost in a transformer becomes heat that cooling systems then have to remove, so losses hit the facility twice — a penalty that is especially acute in the dense, continuous-duty modular and rack systems Bridgeport serves. Moving from ~95% to ~99% efficiency reduces both direct energy cost and cooling demand, improving overall PUE, which is why operators increasingly specify high-efficiency toroidal designs at the UPS, PDU, and conversion stages.
Yes. Bridgeport designs and manufactures standard and fully custom toroidal transformers for UPS, PDU, BESS, and power-conversion applications, including high-frequency cores for solid-state and DC-DC stages — all engineered and tested to spec in Shelton, Connecticut.
Get a Quote on Data-Center Transformer Power
Tell us your voltage, kVA or current, frequency (60 Hz or high-frequency), and footprint constraints — and whether you need isolation, conversion-stage magnetics, or EMI filtering. Our engineers will spec the right high-efficiency toroidal solution for your data-center or AI power design.
