Strength Analysis of Rotor
Rotor design is a complex task which includes input from a series of analyses such as static, dynamics, electromagnetic, thermal analysis.
One important factor that should be mentioned here is the aspect ratio: length to diameter ratio. Low aspect ratio indcates possible issues with critical speeds.
Interconnected parameters are also the following:
- spin stresses
- motor torgue
- rotor dynamic phenomena
- heat loads
Usually PM motors have a ratio of 1 to 3. Depending on the application the max tangential speed is around 100-250 m/s. During rotational loads stresses are generated on tangential and normal/radial directions.
The tangential speed of rotor is
The radial equilibrium equation
The stress strain vector is: