Static modeling of the ultra high speed machine rotor

The ultra high speed machine is a design for applications at speeds exceeding 750,000 RPM. A previous optimization performed on the motor´s design space included several major simplifications in the absence of more detailed data, one of which was the assumption of a constant modulus of elasticity for the motor´s laminated steel rotor. An analytical model was proposed to calculate the deflection of the rotor due to forces encountered during operation based on properties of laminate, adhesive, and filler materials composing the rotor. The elastic and shear moduli of the stack were treated numerically as step functions along the rotor´s length, and an infinitely rigid interface was assumed between every layer. Rotors were fabricated from two different filler materials and tested in bending to compare with results of the model. The model assumed a normal distribution of contact area between each layer of the laminate to account for manufacturing variations. Predicted deflections came to within 9% of measured values at a chosen baseline force of 0.3N for both filler materials.