Study On Intelligent Control Method Of Large Bridge Crane In High Temperature Molten Metal Transportation

The anti-swing control of high-temperature molten metal transport large bridge cranes not only has the common difficulties of ordinary bridge cranes,but more difficulty due to the change of the gravity center of molten metal.In order to solve these problems,the motion characteristics of the crane during the lifting process are analyzed firstly.Then according to the method of mechanism modeling,the nonlinear equations of the crane system model are established using the Lagrange equations.After a reasonable simplification,a linear model of a bridge crane system is obtained and the characteristics of the model are analyzed.According to the mathematical model and control objectives of the crane system,the traditional close-loop controllers are designed then simulated in Matlab.Comparing the simulation results of various controllers shows that the PID controller performance is not bad.To solve the problem of poor dynamic characteristics and weak anti-interference performance of traditional PID control systems,this paper designs a fuzzy self-tuning PID controller based on the parameters tuning method,because fuzzy controllers do not relying on the exact mathematical model.The simulation results show that the fuzzy PID controller is better than the PID controller in terms of positioning accuracy and anti-swing,insensitive to the variation of the internal parameters.And it has a good control effect on the control problem caused by the weight changes of this crane's load center.In order to solve the disadvantages of artificially setting the quantizer and scale factor of the fuzzy controller,the particle swarm optimization algorithm was used to optimize the algorithm.The simulation shows that the advantages of the PSO algorithm compared to the genetic algorithm.Finally,a series of simulation results show that the fuzzy PID controller optimized by particle swarm optimization algorithm has a good control effect.This article relies on the National Key R&D Program of China: “High Temperature Molten Metal Transport Safety Monitoring,Early Warning,and Anti-tipover Technology Equipment R&D(2017YFC0805104)”,which aims to carry out preliminary research work and lay a foundation for further development of the program.