Effect of Air Gap Eccentricity on the Torque and Losses of Bulb Tubular Turbine Generators

The uniformity of the air gap is crucial to the electromagnetic performance of the Bulb Tubular Turbine Generator (BTTG). However, due to factors such as manufacturing tolerances, assembly deviations, and mechanical deformations during operation, the center of the air gap may shift relative to the rotor axis. This air gap eccentricity causes unevenness in the air gap between the stator and rotor along the circumferential direction, leading to a distortion of the magnetic flux density. As a result, the generator's operational stability is compromised, and the fatigue loss of the core material is accelerated. Therefore, the study of the impact of air gap eccentricity on the BTTG is of significant engineering importance for optimizing the generator's structural design and enhancing its operational performance.