The main shaft rotor is the core component of the vane compressor in automotive air conditioning

and its natural frequency and mode shape have direct impacts on the motion stability of the compressor. By means of theoretical and experimental modal analysis

as well as NX Nastran modal computation

the natural frequency and mode shape of the main shaft rotor are obtained. The results show that the natural frequency of the rotor system is greater than 3300Hz

much higher than its working frequency

which indicates high reliability of the motion of the main shaft rotor. Vibration test results prove that the vibration acceleration of the compressor shell is much lower than the upper limit specified value of the GMW standards of the U.S. General Motors Corporation

which ensures that the resonance and the resulting noise and large deformation would not occur in its working process. The analytical results also provide an important reference for fault diagnosis and vibration control of the main shaft rotor system.