Study On Monitoring System For Semi-solid Die Casting Machine Based On HNC And FCS

Since characteristics of die casting that its material can be reused many times and little or no cutting process when machining,it is used in various fields,and its demand is great led by the rapid development of automobile industry.However,with existing domestic die casting machine technology cannot meet the needs of high-end market.The rise of semi-solid casting technology and its advantages has been widespread concern,which promotes research and development of semi-solid die casting machine.Based on the existing basis of the cold chamber die casting machine,this paper analyzes features of the various die-casting machine and applications as well as characteristics of semi-solid die casting machine control system.Aiming at control requirements and precision of semi-solid die-casting machine,a control scheme that programmable controller(PLC)combined with a hydraulic axis digital servo controller(HNC)is used to do hardware design and software design of die-casting machine control system.Electro-hydraulic closed-loop control is used in real-time adjustments of the injection speed to improve the control precision,and remote monitoring system is designed combining with Industrial Personal Computer(IPC)advantages,such as images and data processing,to improve the efficiency of monitoring and management convenience in die-casting machine production.The quality of semi-solid casting depends largely on the performance of the injection system,and the reaction speed of control system is extremely important to improve the injection speed.Aiming at the problems of existing lack of response speed in injection control system,control program that using HNC controller to alone control three-speed injection and the booster shot is put forward.In the premise of ensuring the stable operation of the entire program,the minimum scan cycle of HNC controller is up to 0.5ms,about one-tenth of the general PLC,and HNC controller has integrated and packaged a large number of sophisticated control algorithms for high-speed high-precision electro-hydraulic servo control,which can better meets the control requirements for closed-loop injection control system.In this paper,control network of semi-solid die casting machine is built by fieldbus control technology(FCS),PLC and CNC controller are connected by Profibus-DP and the communication program between them is designed.For the monitoring and management of die casting machine,remote monitoring system based on Industrial Ethernet was designed to realize remote real-time monitoring and unified management in the die-casting production site,save personnel costs and increase productivity.In this paper,model of the BP neural network PID control and SIMULINK simulation diagram are constructed,then BP neural network is trained to get the weights and thresholds by MATLAB,and the simulation is carried out by MATLAB and SIMULINK for control system.The running results of simulation indicate that response time,overshoot,steady-state error and other indicators are better than classic PID control,which meets the requirements of the control system.