Research on vibration reduction of motor by means of decoupling optimum design of its suspension system for a metro vehicle

The motor is considered as a rigid body with 6 degrees of freedom, the free vibration equation of the suspension system is established, taking the decoupling degree as the optimization goal, the motor traverse and floatation frequency as the constraints, Based on the genetic algorithm, the three-dimensional stiffness of the rubber elements of the motor suspension system is optimized; Combined with a subway vehicle dynamics model and field tests, The vibration and stress of the bogie and car body are analyzed when the rigid suspension scheme and the decoupling optimum elastic suspending scheme are adopted. Results show that each rigid mode of the motor can obtain a good decoupling degree, the highest reached 100%, frequencies distribution and expected value are basically the same; Compared with the rigid suspension scheme, when the motor adopts the elastic suspension scheme with optimized decoupling, it can effectively reduce the vibration and dynamic load of the critical parts of the bogie, which effectively reduces the fatigue damage of the bogie.