Research And Design Of Intelligent Electrical Control System Of Grab Ship Unloader

The grab ship unloader is the main equipment for the bulk cargo handling at the port wharf,which is widely used in the transportation and unloading operation of the port enterprises.With the development of large scale transport ships,the depth and width of cargo hold are increased.The unloading time and the clearance time of the original unloading equipment has developed,which can not meet the needs of production.In order to improve the loading and unloading efficiency,this paper puts forward the scheme of applying the PLC frequency conversion control system to the grab ship unloader.The main work of this paper is as follows:First,analyzing the shortcomings of the existing equipment of unloading and determining the direction of development and optimization.Secondly,this paper analyzed the grab ship unloader from three aspects of structure of the loading process,equipment composition and frequency control principle.According to the work mechanism of lifting,luffing and rotary,I designed the optimal transmission scheme,that is based on variable frequency speed control system to ensure the good performance of low speed and high speed.Finally,given the designing scheme of speed self regulation and grab self closing and opening intelligent control system,which is based on S7-300 PLC,transmission equipment ACS880 converter,monitoring equipment of HMI,and PROFUBUS-DP.This scheme is designed from two aspects of hardware and software.Hardware aspect,drawing the electrical control system of the main circuit and PLC control system configuration diagram;Software aspect,drawing the PLC control system flow chart,programming tracking ladder logic program and others.The test scheme is devised to detect the performance.The grab ship unloader,which has driven by this set of electrical control,has been officially put into use at Chizhou Jiuhua Power Company Limited,during the using time,the mechanism meets the design requirements,unloading efficiency could achieve the production needs,which has the very high application value.