Superconductive wire in large motors.
* high efficiency
In cooperation with the US Department of Energy's "Superconductivity Partnerships with Industry" (SPI), Rockwell Automation has demonstrated the capabilities of a 2 hp high-temperature superconducting (HTS) motor with second generation (2G) HTS wire and coils. These efficient high horsepower motors are designed to reduce energy losses by 50%, a significant amount considering that about a third of electrical energy generated in the US is consumed by motors rated at over 1000 hp. The company has being researching superconductivity as a viable energy solution for rotating electric machinery using the first generation of HTS wire since 1994. In 1996, they demonstrated a 200 hp HTS synchronous motor, shortly followed by a 1600 hp motor.
The 2 hp motor demonstration used the HYS ceramic based 2G coated conductor wire from SuperPower Inc., a subsidiary of Intermagnetics General Corp. The motor used 14m of wire, wound into two rotating field coils. "Currently, wire is being made in 100m lengths," says Rich Shiferl, director of advanced technology for Reliance Electric motors, made by Rockwell Automation. "But when the wire is produced at a length of 1000m, we can build a sizable motor and that's when the energy savings will really add up." He says that cost-effective wire is the key to building these bigger motors.
The liquid nitrogen used to cool the HTS coils in the motor is introduced into the center of the rotor, and then the nitrogen gas is exhausted through the motor frame. With a rotor temperature as low as -321[degrees]F, the wire becomes cold enough to exhibit superconducting properties. In a large industrial motor, the coolant will be recaptured from the rotor and rechilled in a closed-loop system to prevent any leakage.
"We see superconductivity as the future of large motors with product potentially being ready for commercial industrial applications in about five years," comments Dennis Goodin, director of strategic planning and business development for Reliance Electric motors.
Rockwell Automation, Greenville, SC
Circle 184, or www.rsleads.com/509df-184
SuperPower Inc., Schenectady, NY
Circle 185, or www.rsleads.com/509df-185
|Printer friendly Cite/link Email Feedback|
|Title Annotation:||Application Xtra|
|Date:||Sep 1, 2005|
|Previous Article:||Connector system.|