Lifting Dynamic Characteristics of Crane with Frequency Control

For purpose of calculating the lifting dynamic load in a crane accurately,a generalized precise direct integration method was proposed to analyze dynamic characteristics of the load-lifting system of the crane.Using this method,the dynamic responses of the system during the load-lifting process of the frequency conversion crane were studied,and the dynamic characteristics of the crane system under various accelerating modes were obtained.The results show that the dynamic lifting coefficient is linear with the lifting speed and exponential with the acceleration time.Compared with the step speed regulation,the frequency conversion speed regulation can reduce the hoisting dynamic load of the crane system by 10% to 60%.