High Current Power Supplies for Superconductors
Superconducting applications demand precise high-current, low-voltage power supplies to energize magnets and test advanced HTS cables. Magna-Power’s current-fed programmable DC power supplies meet these needs by providing robust, scalable solutions complete with flexible cooling, specialized high-current cabling, and ultra-precision measurement accessories.
Introduction to Superconductors
Superconductors are materials that, when cooled below a certain critical temperature, exhibit virtually zero electrical resistance. This remarkable characteristic allows electrical current to flow through them without the energy losses typically associated with standard conductors. The result is highly efficient power transmission and incredibly powerful magnetic fields when these materials are fashioned into electromagnets—both indispensable for advanced applications such as particle accelerators, magnetic resonance imaging (MRI), quantum computing, and fusion plasma.
Historically, these superconducting materials—commonly referred to as Low Temperature Superconductors (LTS)—operate only at extremely low temperatures, requiring liquid helium (4 K, −269 °C) for cooling. While effective, these cryogenic requirements add significant complexity and operating expense, limiting broader commercial adoption.

However, breakthroughs in High Temperature Superconductors (HTS) have dramatically shifted the paradigm. HTS materials, such as those based on ceramic compounds containing rare earth elements and copper oxide (often known as REBCO or YBCO conductors), can achieve superconductivity at higher temperatures—often around the temperature of liquid nitrogen (77 K, −196 °C). Liquid nitrogen, being far more economical and readily available than liquid helium, significantly reduces both capital and operational costs for superconducting systems.
With these developments in HTS, the prospect of widespread, practical superconducting technology has become more tangible. From more compact superconducting magnets in future fusion energy reactors (Tokamaks) to superconducting transmission lines that could revolutionize power distribution, HTS materials are leading the charge in making large-scale superconducting applications both feasible and cost-effective.
DC Power Requirement for Superconductors
Superconductors, by definition, exhibit extremely low—or even negligible—electrical resistance below their critical temperature. This ultra-low resistance environment poses a unique challenge when designing, testing and powering superconducting magnets or testing superconducting cables: the application often requires exceptionally high currents at very low voltages.
Why Low Voltage?
- Minimal Resistive Drops: In superconductors, once at operating temperature, resistive losses are negligible. This means that only a small voltage drop is needed to drive large currents through the superconducting coil or cable.
- Safety and System Complexity: Keeping supply voltage low mitigates electrical insulation requirements and reduces safety hazards in high-current test setups, especially in research or industrial lab environments where multiple power systems may be operating side by side.
Why Very High Current?
- Magnetic Field Requirements: Superconducting magnets used in fusion research, like those in Tokamak reactors, demand powerful magnetic fields. To generate these fields, engineers employ large coils that must carry currents ranging from thousands to hundreds of thousands of amps.
- Superconductor Qualification and Testing: Organizations developing high-temperature superconducting (HTS) wires need to characterize their performance under realistic operating currents, requiring the ability to deliver high currents accurately and reliably.
Programmability for Ramping and Control
- Smooth Ramp-Up and Ramp-Down: Superconducting magnets are often sensitive to rapid changes in current, which can induce mechanical stress or lead to a quench (a sudden loss of superconductivity). Programmable DC power supplies allow precise current profiling, ensuring controlled energizing and de-energizing of superconducting systems.
- Automated Testing Protocols: In R&D and production environments, superconductor characterization frequently involves repeating complex current profiles under various conditions. A programmable supply lets engineers automate these processes, improving consistency and data accuracy.
Magna-Power’s High Current Programmable DC Power Supplies
Magna-Power’s high-current power supplies have been integral to superconducting load applications for decades. Whether it is energizing Tokamak field coils for fusion experiments or powering superconducting wires during testing and validation, Magna-Power’s combination of vertical integration, current-fed topology, flexible cooling solutions, and deep engineering expertise allows it to deliver high-current solutions optimized for safety, performance, and reliability. The company’s ability to process raw materials and engineer high current bus bar solutions in-house means Magna-Power can rapidly iterate on new designs, and integrate the latest-and-greatest power semiconductors to expand its product offering.

Standardized products into the 100s of kiloamps with reliable current-fed power processing
Magna-Power’s standard TS Series power supplies spans hundreds of models and thousands of configuration, capable of providing currents ranging from a few amps all the way into the hundreds of kiloamps. Low voltage, high current models, for example, include the TSD10-2000 (0-10 Vdc, 0-2000 Adc, 4U), TSD10-4000 (0-10 Vdc, 0-4000 Adc, 8U), TSD10-6000 (0-10 Vdc, 0-6000 Adc, 12U), and TSD10-8000 (0-10 Vdc, 0-8000 Adc, 16U). Multiple TS Series units can be configured in master-slave parallel to achieve higher current levels.
Each model leverages the company’s current-fed power processing topology, which ensures stable current output under resistive, capacitive or highly inductive loads, high fault tolerance, and predictable system behavior under demanding load conditions. These standard configurations offer a direct path to scaling your power needs while simplifying the complexities often associated with ultra-high current applications.
With a deep legacy of powering superconducting programs, Magna-Power’s programmable DC power supply family continues to evolve to meet the stringent power demands of both industrial and scientific users alike.
Flexible cooling solutions and integration options
Magna-power’s rack enclosures provide a variety of flexible, turn-key, installation and cooling solutions to match specific installation requirements. These enclosures can accommodate air-cooled or water-cooled TS Series power supplies, often combining multiple units into a single solution:
- Integrated cooling systems: Air cooled products integrated into a rack include top-mounted fans to draw in cool air and exhaust the heat from the top. For water cooled units, manifolding is provided to a common inlet and outlet for the rack, easing connections to facility water supplies.
- Harmonic neutralization: Large rack enclosure systems can include optional input harmonic filters, ensuring low total harmonic distortion (THD-I) when running multiple high-current supplies in parallel.
- Accessories available: Magna-Power offers a variety of rack accessories, such as AC breakers, common AC inlet bus bars and distribution, emergency stop buttons, floor-mountable bases, among others. A rack configuration is defined together and unique identifier provided for reference.
With these comprehensive integration options, your ultra-high current power supply solution remains both modular and manageable, simplifying everything from procurement and setup to ongoing operation and maintenance.

High current cabling for simplified integration
High-current superconducting applications often demand specialized connectors and cables capable of carrying thousands of amps without excess heat generation or voltage drop. Often, these high current connections require fabrication of large custom copper bus bars, which demand engineering resources and can be very costly.
Magna-Power offers high current, extremely flexible, high strand-count, and low impedance cabling specifically engineered for pairing with its TS Series bus bars, with key features as follows:
- High durability insulative sleeving: Cables are protected by an acrylic coated braided fiberglass sleeving, providing high abrasion resistance (2500 cycles, SAE ARP 1 536) and 6,000 Vdc insulation, ensuring durability and long service life in industrial or R&D environments.
- High current capacity: Each cable is 1,000 Adc and is extremely flexible with low impedance (0.020 mΩ/ft). Multiple cables can be connected in parallel to meet even higher current requirements. Each TS Series bus bar includes enough connection points to allow the full current to be carried by the cable.
- Various length options from 1-ft to 300-ft: Simplify installations where equipment or test stands may be located at various distances from the power supply.
By combining these purpose-built cables with TS Series power supplies, Magna-Power takes the guesswork out of high-current integration, ensuring both safety and ease of installation.
Ultra-precision add-on or DIY inputs
For applications requiring ultra-precise measurement and control—whether that’s to finely tune a superconducting magnet’s field uniformity or to characterize the nuanced behaviors of HTS cables—Magna-Power offers the DBx Module. This add-on accessory provides:
- High precision: High-performance D/A and A/D converters with a temperature stabilized controller provide highly granulated programming (18-bit) and readback (24-bit) resolution.
- High-Stability: An ultra-stable fluxgate direct-current current transformer (DCCT) is used to take high accuracy isolated measurements from a series connection with the power supply’s DC output, then drive the power supply’s analog inputs with the DBx Module’s temperature stabilized controller, providing stability < 50 ppm.
- Turn-key Configurations: Systems shipped and tested directly from the factory, fully integrated with the power supplies, DBx Modules, rack enclosure, cabling and cooling.
For customers that want to provide their own high precision reference and perform external error correction, Magna-Power provides analog inputs to its power supplies, which is a direct analog path to our controller.

Summary
Superconducting applications—from the ultra-powerful magnets essential in fusion reactors like Tokamaks to new high-temperature superconducting (HTS) cables—demand precise high-current power supplies operating at low voltages. In this article, we explore how these challenging requirements are met by Magna-Power’s robust, programmable DC power solutions. Leveraging a unique current-fed topology, Magna-Power delivers standard power supplies capable of reaching hundreds of kiloamps, offering flexible cooling, simplified integration with specialized high-current cabling, and optional ultra-precision measurement via the DBx Module. With decades of experience and a vertically integrated USA manufacturing approach, Magna-Power stands ready to tailor each system to meet the specific demands of superconducting research, testing, and industrial-scale implementation.