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At most plants, the biggest challenge in tuning PID controllers is to reject process disturbances. However, in many PID controller’s information regarding process disturbances is missing in the PID algorithms which drastically affects PID performance. Do you need to understand how to add that information in PID controllers? Check out this blog, about the benefits in feedforward in PID controllers.

The key objective for a DCS engineer is to make sure automated operations run as smoothly and as safely as possible. You want to keep the operators as happy as possible - which means keeping the alarms to a minimum and prevent operator interventions. The impact of optimal PID tuning on smooth and safe operations and the number of operator interventions, cannot be overestimated. With a fully-booked schedule, PID tuning is often something that has a lesser priority.

In this blog, we want to explain the impact of the PID tuning on the operator interventions. The first objective of this blog is to put PID tuning higher on the priority list. The second aim is to provide you a way to achieve better tuning within a minimum of time and on a first-time-right principle.

Many tuning methods are proposed for PID controllers, of which trial and error is the best known and used method. Despite its popularity, the biggest downside is that it’s time-consuming and it doesn’t guarantee a robust and stable solution. The Ziegler-Nichols method is a good alternative but doesn’t always provide optimal performance. In this blog, you will read why Ziegler-Nichols isn’t always the right choice to achieve stable and robust control loops.

The period before a plant’s launch is a stressful time. There is a possibility you will face mechanical problems, errors in the instrumentation and DCS configurations, safety issues and even last minute changes in control designs.

When a plant is commissioned, all the equipment and all safety and control systems are tested. However, this doesn’t mean that, at this stage, the plant is tuned to generate the most optimal results. In this blog, you will read why it’s important to start with PID tuning in a plant’s commissioning phase.

When we work with PID controllers, we always assume that the control valve flow characteristic is linear. PID controllers cannot handle nonlinear responses properly. However, most of the time valves are nonlinear and we have to deal with them when tuning a loop. Process units that change their operating window regularly, have the tendency to affect the performance of the PID controllers. This probably has happened to you before and i know it's really frustrating! But I'll show you a PID tuning example where it's possible to tune a PID controller and have a good performance on a large operating window of a process unit. And that is what I will explain in this blog.

From furnace or boiler efficiency point of view, excess air control is very important to be set up correctly. When there is too much air in the combustion process, additional fuel is being burned to raise the temperature of this excess air to the combustion temperature. Excess air absorbs the heat that goes up the stack, rather than in the process. To control the excess air to its minimum level, it's required to control it tightly in a “safe way”. If there is not enough air being introduced into the combustion process, all fuel will not be burned and, consequently, it will be lost up the stack in the form of combustibles. Not only does this result in an obvious waste of valuable energy, safety and pollution hazards are created. 

Discover in this blog how to reduce specific energy consumption of furnace or boilers by implementing the correct control strategies. 

When the grass root plant starts production, 70% to 80% of the PID loops are in default mode. There is nothing wrong with default settings. However, when time passes and alarms occur, the production manager will complain about spending too much time on controlling the plant. You need to check all the PID loops to make sure the plant will run smoothly. In this blog, you will read 5 of the most common mistakes made by DCS engineers in PID tuning. And more importantly, how you can avoid those mistakes.

Tuning of PID controllers has shown to improve plant performance and increase stability and safety. Very often, single control loops are tuned with the focus only on that specific loop, without regard for process interaction with other control loops. Depending on the nature of the process, this interaction can lead to a destabilizing effect where the control loops fight each other instead of working together in harmony. Discover in this PID tuning example how to analyze and tune interacting loops in this blog.

In most of the chemical and metallurgical industries a furnace or heater is the most common and important thermal equipment used. Some control schemes have been recognized for automatic control of furnace outlet temperature, cascade control of temperature with fuel, control of fuel to air mixture ratio, and excess oxygen control content in flue gas. The design of a control scheme is very important, and it may vary as per the process and plant requirement. The final control performs well only if the underlying PID loops are designed and tuned correctly. Without robust and safe PID tuning parameters, tight and safe control of the furnace outlet temperature is not possible. Picking the correct temperature control scheme design and tuning the PID loops in it properly are equally important. In this blog you'll learn about PID tuning of a furnace.