Research On The Monitoring System Of Heating Based On LabVIEW

The unattended heat-exchanger station is the key factor of heating control.With thedevelopment of computer control technology, it is getting more and more highly combinedwith the heat-exchanger station operation control and the computer control.Because theapplication of the computer control system can make the heat-exchanger station run indifferent thermal conditions, it can improve the efficiency of the unattended heat-exchangerstation operation.Operation control system control and operate automatically according to thecollection temperature and flow rate,pressure and operation parameters.This paper designed heat-exchanger station monitoring system combined LabVIEW andPLC,and PC using LabVIEW graphical language to write HMI. The next-bit machine withPLC to control the heating exchanger station process equipments.Through the Modbuscommunication protocol to make an connection between PC and PLC. Completied of theheat-exchanger station centralized monitoring and management.The main contents are asfollows:1、Analysis the development status of foreign and domestic automatic control technologyand monitoring technology. Then study the characteristics of heating exchanger station systemand analysis its control theory.2、Highlight the inverter and PLC constant pressure and temperature water supplycontrol program.Gives the control algorithm implementation process.classical control theoryof PID.3、Establish math model of heating exchanger station system,while establishing mathmodel between secondary temperature of supply and return water and outdoortemperature.According the dynamic model to design the decoupling control scheme ofPID.Using MATLAB simulation tool draw PID response curve plotted under differentconditions.4、Elaborate the monitoring control principle of heatinging monitoring system,usingLabVIEW as a platform to compile interface of PC.Including system data modules, systemmonitoring module and information management module and so on.Aiming at the real-timeproblem,designed clients real-time database system.5、Follow the communication protocol of Modbus and set the relevant parameter andcheck code.PLC and LabVIEW completed communication.Using the VISA serial inLabVIEW designed serial communication.The test results show that the system running stable enough to meet process requirements.At the same time not only improving the degree of automation but also saving energy andreducing the staff’s labor.There is an important significance to improve the management levelof the heat-exchanger station monitoring system modern.