Superconducting motor in recent 2-hp demo
High temperature superconducting (HTS) technology holds the promise to make electric motors optimally efficient. However, not everyone agrees about the superiority and expected cost-effectiveness of second-generation (2G) HTS wire used for the first demonstration of a 2-hp HTS motor.
High temperature superconducting (HTS) technology holds the promise to make electric motors optimally efficient. However, not everyone agrees about the superiority and expected cost-effectiveness of second-generation (2G) HTS wire used for the first demonstration of a 2-hp HTS motor, described in last month’s newsletter (and Control Engineering ’s July 2005 News section ). The motor, built by Rockwell Automation Power Systems, relies on 2G HTS wire made by SuperPower Inc . (a subsidiary of Intermagnetics General Corp.) to make this technology practical.
Mark Bitterman, executive editor of Superconductor Week (a newsletter of record for the superconductor industry), took issue with some assessments about the relative maturity of high temperature superconducting technology. Dr. Rich Schiferl, Rockwell Automation’s director of advanced technology for Reliance Electric motors, provided input to the subject HTS motor update article. The 2-hp HTS motor demonstration took place at Rockwell’s Advanced Technology Laboratory (Cleveland, OH) in early June 2005—in cooperation with the Department of Energy’s (DOE) Superconductivity Partnerships with Industry (SPI) program.
“…the belief that 2G wire will be cost-effective in five years is a very vague statement. This is to say that there is no way 2G will reach Department of Energy cost-effectiveness targets of $10-$15 per kA-meter,” says Bitterman. “In fact, most people who actually make HTS wire believe that 1G will continue to be lower cost and higher quality than 2G for the foreseeable future (certainly more than 5 years). Basically, the technology of 1G is about 15 years ahead of 2G, and is only just now starting to see a few applications look more-or-less viable on the one- to two-year horizon.”
Contacted about those views, Schiferl stands by the position that first-generation HTS wire will “never be inexpensive enough to be able to sell eventual HTS motors” to the market. A series of development steps and actual results, not forecasts, will ultimately determine which wire technology will prevail for HTS motors.
—Frank J. Bartos, executive editor, Control Engineering, firstname.lastname@example.org