Design And Development Of A Debugging Experiment Platform For PID Parameters Of PLC Control Software For Industrial Processes

In industry process control using PLC as control system, finding suitable PID controller parameter is an important condition before control system is put into operation. Although there are a variety of PID parameters-tuning algorithms, parameters applied to industrial site still need trial and error. Debugging and tuning of controller parameter in industrial site requires process control system connected to the controlled process, the controlled object starting and the production process running, and debugging process will inevitably introduce disturbance to the production process. It will make a very important practical significance for shortening debugging time, saving labor investments, reducing debugging risks and costs if we test the controller parameters in laboratory in advance.This project has been supported by National Science and Technology Supporting Program "Advanced Control Technology of Whole production Line of Mineral Processing" (2012BAF19G01) studied and discussed PID controller parameters debugging methods of PLC software, designed and developed a platform for PID parameter debugging based on Rockwell PLC software and MATLAB software, which is expected to provide effective technical support for PLC on-site debugging. The details are as follows:1. Questions and test requirements of PLC software PID parameter debugging are discussed in detail on the basis of a comprehensive review on parameter debugging technology of PLC control software.2. For the common time delay inertial controlled object in industrial process, this paper studies the experimental method based on simultaneous time scale transition between PID parameters and the virtual object model parameter of PLC software, which can effectively shorten debugging time.3. Based on human-computer interaction, a debugging experiment platform for PID parameters is proposed. Whole framework of platform for PLC software PID parameter debugging consisting of virtual objects module, tags butting module, time scale transformation module, performance index module, test records module, human-machine interface module, run-manage module and communication module is designed, which can realize semi-automatic parameters test of simulated industrial site and generate test reports automatically.4. Based on the development environment of Rockwell’s PLC software and MATLAB software, this paper has developed a debugging experiment platform for PID parameters of PLC control software for industrial processes by using DDE and OPC communications technology.5. With the PLC loop control program of an iron plant in industrial automation engineering as a case, the debugging experiment platform for PID parameters of PLC control software has been tested. Test results show that by means of this debugging platform, software debuggers can quickly test corresponding control effect of PLC controller parameters, which makes a contribution to shortening field debugging time, saving labor investments and reducing debugging risks and costs.