Compact and low cost magnetic bearing with saturated coil for gas turbine generators

A novel magnetic bearing system for gas turbine generators of next generation nuclear power plant is proposed. This system newly adopts saturated coils for generating main bias force and small size linear auxiliary coils for stabilizing the suspension. The saturated coils operate in the region of magnetic saturation in order to maximize the magnetic flux density and reduce the bias current. This results in compact size of core, significant reduction of copper loss; hence, a low cost and high efficiency magnetic bearing is achieved. The proposed system is under development for the goal of 50 ton rotor mass and 300MWe project.