Moving a step forward in its goal of making energy-saving technology commercially viable, Rockwell Automation, Greenville, S.C., successfully demonstrated the capabilities of a 2-hp Reliance-Electric high-temperature superconducting (HTS) motor with second-generation (2G) HTS wire and coils.
The test, completed in cooperation with the U.S. Department of Energy's “Superconductivity Partnerships with Industry,” makes possible the commercialization of super high-horsepower motors, designed to reduce energy losses by 50%.
The demonstration used new HTS ceramic-based second-generation coated conductor wire from Super-Power Inc., a subsidiary of Intermagnetics General Corp. This was the first time 2G wire was used to create coils large enough — 14 m of wire wound into two rotating field coils — for a 2-hp electric motor.
According to Dennis Goodin, director of strategic planning and business development for Reliance Electric motors, “We see superconductivity as the future of large motors, with product potentially being ready for commercial industrial applications in about five years.”
The need for superconducting motors has escalated with the rise in energy demands and costs. With 33% of electrical energy in the U.S. being used to power 1,000 hp motors and larger, it is necessary to find a smaller, lighter, and more efficient motor for continuous use.
This is the latest breakthrough by Reliance Electric, which has pioneered new technologies under SPI since 1994.
Rich Schiferl, director of advanced technology for Reliance Electric, says cost-effective wire is key to the recent breakthrough. “Currently, wire is being made in 100-m lengths,” Schiferl said. “But when the wire is produced at a length of 1,000 m, we can build a sizable motor, and that's when the energy savings will really add up.”
Liquid nitrogen cools the HTS coils when introduced into the center of the rotor as gas exhausts through the motor frame. The temperature in the rotor is about -321°F, allowing the wire to produce superconductive properties. In the HTS motor, a closed-loop cooling system recaptures and re-chills the coil coolant to avoid gas or liquid leaks.