PID Control with Gain Scheduling and PID Tuning
Objective of the Application
The objective is fast and tight control of processes with non linear behaviour, which requires different control parameters for each operating point. Using gain scheduling, i.e. an operating-point-oriented parameter control, the quality of control can be improved significantly. The scheduling implies a feedforward adaptation of parameters according to a defined schedule in opposite to an adaptive controller, which permanently identifies its process model based on new measurement data.
The application example considered here shows a control loop with PID controller and gain scheduling based on the corresponding process tag type of the SIMATIC PCS 7 Advanced Process Library.
The following main points are discussed in this application note:
- How to create an instance and set the parameters of the process tag type.
- How to determine the process model and the control parameters. The usage of the PCS 7 PID Tuner is explained firstly for linear processes, and afterwards for a nonlinear process.
- Benchmark simulations with and without gain scheduling, to show the potential benefits.
… valid for PCS 7 V7.1, in principal transferable to V7.0 from SP1.
|Content of the downloads||
|PID Control with Gain Scheduling and PID Tuning|
|10/2009 V1.0||First release|