Losses estimation, thermal-structure coupled simulation analysis of a magnetic-bearing reaction wheel

Magnetic-bearing reaction wheel (MBRW) can be applied to stabilizing satellites with stringent pointing accuracy. Temperature rise subjected to losses is a key issue for a MBRW. The prediction models of iron loss and copper loss for magnetic bearings and BLDCM are established, and the loss coefficients of iron core are determined by measured loss curves at different frequencies. The copper loss distribution and iron loss distribution of the MBRW are investigated. Based on the loss values, the heat generation rates of the different parts in the MBRW are calculated, then the thermal field of the prototype is analyzed by 3-D finite element model. Thermal-structure coupled analysis of rotor is also investigated. Finally, the prediction and analysis of losses are verified by experimental results in a prototype of MBRW with rated speed of 5000 r/min and rated angular momentum of 15 Nms.