Submerged gas-circulator motors for advanced gas-cooled reactors

The paper, describes the historical background, development, design, execution and works´ full-power full-pressure tests of submerged gas-circulator equipment rated 5 MW at 3000 rev/min for 11 kV, 50 Hz, 3-phase supply. The environmental requirements, due to the nuclear reactor, of 40 atm of CO2 with operation down to 1 atm of air, need careful consideration from various motor-design aspects: aerodynamic, thermodynamic, lubrication, dielectric etc. The complex equipment requires the closest integration of design between the `mechanical¿ and `electrical¿ constructor as well as the reactor constructor, and illustrates several interesting and/or novel features. Brief mention is made of the impact of changing the environment to helium.