Welcome to Steel Information



High Temperature Superconducting Motors to Trial in Navy Ships

American Superconductor Corporation, today announced it has been awarded an $8 million contract by the US Navy's Office of Naval Research (ONR) to build and deliver a 6,500 horsepower (hp) high temperature superconductor (HTS) motor designed for ship propulsion. The contract represents the fourth ONR contract with American Superconductor focused on developing HTS motor technology for future Navy electric warships.

Under the ONR program, American Superconductor will deliver a factory-tested AC synchronous HTS motor, integrated with a commercially available power electronic drive system that will be suitable for shipboard at-sea trials. The 6,500 hp motor developed under this contract will operate at 230 revolutions per minute (rpm) and represents a ten-fold increase in torque over the 5,000-hp, 1,800 rpm HTS motor AMSC built and tested during 2001. The low-speed, high-torque 6,500 horsepower HTS motor is a critical development milestone on the path to 20,000-hp and 35,000-hp motors, which are the power ratings expected to be utilized on electric warships and on large cruise and cargo ships. HTS motors of these power ratings are expected to be as little as one-fifth the volume of conventional motors.

"This is the first HTS motor designed specifically for ship propulsion," said Greg Yurek, chief executive of American Superconductor. "The increased power density and efficiency of our proprietary HTS motors allow ship designers to create new types of ships not possible with conventional motor technology. Our previous HTS motor projects have brought us to the point where we believe the technology is ready to demonstrate in an actual ship installation. The contract calls for delivery of the motor to the Navy in the summer of 2003, enabling sea trials before the end of that year. We believe we are on track to be producing similar HTS motors for commercial sale in 2004."

Industry experts project that the global market for electric motors and generators for electric ship propulsion will grow from $400 million per year today to $2 billion to $4 billion per year in ten years, a compound annual growth rate of more than 20 percent. The Secretary of the Navy announced two years ago the Navy's intention to build on the revolutionary conversion to electric propulsion systems that occurred in commercial ships during the last decade. Today, low-speed, high-torque electric motors are used in most commercial cruise ships and many cargo ships to directly turn the propellers that drive the ships. Electricity to run the propulsion motors is provided by electrical generators, which are driven by diesel engines or turbines.

In addition to being a critical product development milestone, the low-speed, high-torque 6,500-hp motor is the power rating required today to propel many types of passenger and merchant vessels including container ships, passenger ferries, so-called Roll-On, Roll-Off merchant cargo ships, and tankers carrying a wide range of materials.

The significant advantages of HTS motors in efficiency, weight and volume relative to conventional motors are expected to enable ship architects, builders and operators to capitalize on more cost-effective designs that allow more cargo or passengers to be transported, and in some applications, at increased speeds.

This ONR contract builds on results AMSC achieved in three earlier Navy development projects in which the company successfully designed and built components and created conceptual and preliminary designs for a range of HTS AC synchronous ship propulsion motors. Under the current contract, finalisation of the design and the fabrication of the 6,500-hp motor and its integration with a marine power electronic drive will span a 17-month period.