Integrated online auto-tuning and digital implementation of PID controllers in industrial processes

The continued progress and growth of industry has increased the need for communication and control integration. In this regard, it would be interesting to apply simple algorithms that combine model parameter identification and tuning of PID controllers. In this work we consider the digital implementation of a PID self-tuning system formed with an industrial PLC and a PC. The PLC is used acquire field data whereas the PC is used to run a Matlab program to perform parameter identification, PID parameter tuning and control. Communication between the PLC and the PC is carried out by means of an OPC (Ole for Process Control) server. The proposed scheme has been applied to the design of a PID controller for a pressure control station of a natural gas pipeline.