Category: Cascade Control Cascade Rule Interaction Resonance Disturbances PID Controllers PID Tuning Tips
Submitted by Greg McMillan on Wed, 04/15/2015 - 21:25
Most of the control literature focuses on minimizing the integrated absolute error (IAE) for a step disturbance, often in a linear system. In the process industry, there are many other objectives and complications that require special attention.
Submitted by Greg McMillan on Mon, 02/09/2015 - 20:58
A lot of time and money can be spent deciding which valves need positioners and which flows need measurement. We tend to look at short term costs such as hardware and not the cost of troubleshooting and the implications as to plant performance.
Category: Cascade Control Cascade Rule Lambda PID Tuning Rangeability Tips Ultimate Period Valve Positioners
Submitted by Greg McMillan on Fri, 03/21/2014 - 11:09
Given that cascade control loops are everywhere without much consideration as to dynamic requirements, what can we do to make the implementation effective? Here are some specifics by the way of detailed recommendations on the sequence, speed, and setup for tuning PID and digital valve controllers.
Category: PID Tuning Cascade Control Ultimate Period Tips Cascade Rule Lambda Valve Positioners Rangeability
Submitted by Greg McMillan on Sat, 03/08/2014 - 20:16
Did you know all loops today use cascade control? Do you understand how cascade control can correct for lower loop disturbances before they affect the upper loop and can make the upper loop faster? Do you know what to do to keep the system from oscillating if the lower loop...