To improve the maximum speed and power density of a cage-type solid rotor induction motor

the rotor's outer diameter and structure of a 120 kr/min high-speed cage-type solid rotor induction motor were designed based on an analytical model of rotor strength. First

based on the theories of discs and hollow cylinders

stress field models were established for the solid rotor and hollow end ring

respectively. Then

by adding a sleeve to the end ring and further reducing the risk of end ring fracture through interference fit

the stress fields of the solid rotor

end ring and sleeve are coupledly calculated based on the analytical calculation theory of sleeve interference stress

centrifugal stress deformation theory and high-temperature thermal expansion theory. Effects of temperature and end-ring sleeve interference were analyzed on the rotor stress and combined with the ultimate tensile strength of various materials

the outer diameter of the rotor was preliminarily determined. Furthermore

different rotor structures were proposed and finite element models were established to compare the advantages and disadvantages of different structures

ultimately determining the optimal rotor structure with a rotor tip speed of 226 m/s. Finally

a prototype was machined and no-load tests were conducted at a maximum speed of 120 kr/min. The experimental results show that the motor operates smoothly

with good current waveforms

verifying the correctness and effectiveness of the rotor structure designed in this study.