Re-Design Blocking End Winding Rotor Generator To Prevent Extreme Expansion of Coil Towards Axial Direction: A Case Study

Rotor generators with a thin coil structure will expand easily, both radially and axially, however it is vulnerable to axial blocking if it is not able to withstand the expansion movement in the axial direction, causing coils between slots to touch each other, so that interturn short occurs. The case study conducted is aimed at determining the blocking design to anticipate coil expansion. The method is to identify problems, re-design, simulate applications and implement axial blocking with a new design. Based on the calculation of expansion, especially in the outermost slots 6, 7, and 8, with an expansion delta value greater than 1 mm, it is fundamental to redesign the axial end winding blocking in order to dispel expansion coil delta. Case studies of extreme expansion in the axial direction for coils with thin structures can be done through re-designing end winding blocking to prevent electrical faults, and the benefits of this re-design can be applied to generators with the same coil structure.