There are many critical PID loops in an operating plant. Operations managers typically like to minimise changes on tuning parameters on such PID loops, quite often maintaining the status quo, even if improvements are possible or desirable. The performance of such PID loops could be optimised if they could be inserted in manual mode followed by moving the output a few times, collecting data, and calculating PID tuning using PID tuning software. Unfortunately, operations managers may not allow you to insert this critical loop in manual, so how can you calculate PID tuning parameters for such a loop while maintaining it in closed-loop mode? In this PID tuning example, we’ll show the best practices and pitfalls.
Operations managers have many priorities to juggle in their workday. Some of these activities are completing emergency repairs, resolving instrumentation issues, meeting production targets, preparing and presenting reports. When a company purchases a new APC projectit may fall to the bottom of the priority list due to other activities requiring more attention. Why is it important to start APC activities soon after the contract award? What are the convincing arguments for operations managers that will help them move the APC project higher up the priority list and start implementation as soon as possible?
Every DCS has its own set of PID loop equations. A Honeywell Experion DCS features 5 different equations and an Emerson Delta-V DCS can even offer 7 equations. Each equation implies a different formulation of the PID control algorithm. So, each equation might require different tuning parameters to obtain the same or similar closed-loop behaviour. Many control engineers ignore the equation type of a PID loop. Even if you have tuned many different loops, you might not be able to obtain the desired closed-loop performance if you don’t have the right equation selected.
Your ultimate goal as a DCS engineer is to get the most out of your plant operations. Over the years you’ve developed your own rules of thumb and used your gut-feeling to tune your PID loops. Most of the time this works well. But what if I told you PID loops can be tuned the first time right? INCATools — a set of PID tuning and process control tools — enables this. It is developed to overcome the challenges you face everyday. In this blog, I tell you about the top 5 reasons to use INCATools as a PID tuning software to tune PID controllers.