Behavioral Pattern of Brushless Flux Switching Wound Field Machine: A Focus on Static Rotor Eccentricity

In the practical manufacturing of electrical machines, inaccuracies during production and assembly can result in the misalignment of the rotor and stator. This misalignment, in turn, results in an uneven air-gap magnetic density, significantly affecting the operational performance of the machine. This study explores the impact of static eccentricity on critical parameters, such as flux density, average and cogging torque, and losses under diverse operational conditions. Healthy and eccentric brushless stator-mounted machine models were established using ANSYS Maxwell 2D software. The results indicate that as the static eccentricities increase, the copper loss remains unchanged. However, the core losses exhibit slight variations: 1.52% to 2.93% at half load, 1.45% to 5.85% at rated load, and 0.94% to 2.80% at overload. The output torque experienced a slight increase, whereas the cogging torque underwent a drastic increase. The rising eccentricities suggest potential saturation effects that influence magnetic characteristics and overall motor performance. Understanding how static rotor eccentricity impacts saturation is crucial for optimizing designs and addressing challenges associated with such operational conditions.