07-04-2009, 11:09 PM
class of synchronous rotating machines (Super motors and Super generators) that can generically be categorized as Super machines. Compared to the conventional machines of equivalent rating, these Super machines are less expensive, lighter, more compact and efficient. The field windings are made with HTS conductor material which operates at 35-40 K and can be cooled with inexpensive cryocoolers. These advanced machines are attractive for use and at present they offer significant developments in ship propulsion techniques. In many modern ships, propulsion systems are so large and heavy that they force the rest of the ship to be constructed around them. Large ship propulsion system could be made more compact and lighter by application of High Temperature Superconductor (HTS) technology, thus providing relief from this constraint. HTS machine technology is maturing rapidly and marine ship drive applications are expected to benefit greatly from these advances. This paper discusses the application of HTS machines in ship propulsion. On the basis of experience with recent HTS ship propulsion, it can be concluded that the superconducting rotating machines will deliver superior performance both during steady-state and transient modes of operations. HTS rotating machines will be more compact, lighter, and more efficient than the conventional machines. Naval architects can now begin to translate these propulsion system improvements into increased profitability for ship owners and operators. This progress has been achieved due to the recent progress in key enabling technologies, such as HTS wire and cooling systems. Their small size and weight will translate to lower cost. HTS windings operating at an easily attainable temperature level (~35K), and cooled with low cost and dependable off-the-shelf refrigerators, will result in the fielding of highly reliable superconducting machines. The key technologies essential for the successful development of commercially-viable superconductor machines have been proven and are now sufficiently robust, as well as cost-effective. HTS rotating machines for electrical grid stabilization, industrial and ship applications are just now becoming commercially available and can be expected to become increasingly widespread over the next several years.
