Design And Fault Diagnosis Analysis Of Engine Room Alarm Monitoring System Based On PLC

The nacelle alarm monitoring system is an important part of ship automation.It can accurately and accurately reflect the operating status of various power equipment,control equipment and electrical equipment in the nacelle.As long as the system detects that the monitored equipment has malfunctioned or is abnormal,the system will trigger The alarm mechanism activates sound and light alarms and informs other duty cabins by extending the alarm board.All alarm conditions are recorded and printed out.The system will monitor the parameter status of various monitoring points in the cabin in real time.The relevant operation information will be displayed on each monitoring screen,so that the operator can clearly understand the real-time operating status of the ship.These displays are usually placed in a central control room or an extended alarm panel.Considering the backwardness of our country's relevant technologies in the current large environment,after reading the literature on the cabin monitoring system of the relevant ship,this paper will design a set of ship cabin alarm monitoring systems that are feasible and meet relevant regulations.The thesis first introduces the background and significance of the cabin alarm monitoring system,combines the basic functions and design requirements of the system itself,elaborates the research status of the system at home and abroad,and gives the overall design plan.The lower computer of the system adopts Siemens S7-400 as the controller,in which data acquisition and PLC CPU module use PROFIBUS communication between the host computer and the PLC module using industrial Ethernet to achieve data sharing.The programming software uses Step-7 software developed by Siemens to realize the hardware configuration and the creation of the network structure.The programming language adopts the ladder language method,which is easy to understand and straightforward.The whole system adopts a modular programming concept and involves OBs.Modules,DB modules,FB modules,and FC modules.After the system is designed,a new fault diagnosis system based on neural network algorithm will be designed from the theoretical point of view.This part will study the model structure,parameter setting,training function of BP network algorithm,RBF network algorithm and ELMAN network algorithm in detail as well as the respective advantages and disadvantages of each function.The fault diagnosis object is the ship supercharging system.The network model is trained by fitting the historical data,and the collected data is used asthe input of the network model to realize the recognition of the system failure and the effect of the prediction.In the end,aiming at the shortcomings of the neural network model itself,an optimization scheme based on genetic algorithms is designed.The genetic algorithm is used to optimize the thresholds and weights of the neural network based on its strong convergence characteristics,so that the prediction accuracy of the neural network is improved.Improve the accuracy of fault diagnosis and achieve optimal forecast results.