Superconducting rotating machines: A review of the past 30 years and future perspectives

Abstract

Research and development of superconducting rotating machines has a history spanning greater than 30 years. Earlier, superconducting homo-polar DC machines that used low temperature superconductors may have found the first practical applications in superconducting rotating machines; however, it cannot be said with certainty, given their use in secretive war ships. Superconducting synchronous generators cooled by liquid helium are well developed, particularly by the Super-GM project in Japan. The paper discusses fundamental subjects in the design, manufacture, operation, control, and performance in power systems. The development of oxide superconducting wires and bulks, has found applications in superconducting electric motors (mainly synchronous ones), the structures of which are very similar to the generators. The paper also discusses the power system problems addressed by superconducting equipment, which have arisen due to the increase in the number of renewable sources of energy. The paper assesses the solutions offered by superconductivity to the above mentioned challenges.