Smith Predictor Control for dead time


Thread Starter


I want to control a plant that has a dead time due to the length of the gas line and a tank. To control it fully, I need a smith predictor. Can any one send me a simple Smith predictor control that will control this animal.

Thanks in advance
Here is an on-line article for the Smith-Predictor: A188333

The concept is that the process is actually controlled by an ordinary PID controller using the process model as the input (feedback) signal, and with outputs to the control valve and the process model at the same time. The process model is usually a Lead/Lag block and does not reflect the deadtime. The process model output passes through a Deadtime block and is compared with the process feedback to determine how good the model is at predicting the process. Any error is used to tune the process model to make it work better. The Deadtime block should have its deadtime adjustable for process throughput. The gain of the lead/lag is usually adjusted by model error.

Dick Caro
Richard H. Caro, CEO
CMC Associates
2 Beth Circle, Acton, MA 01720
Tel: +1.978.635.9449 Mobile: +1.978.764.4728
Fax: +1.978.246.1270
E-mail: [email protected]