In most process plants there are one or two operators that seem to drive the process better than others. Those operators consistently create the most output at the highest quality, and can manipulate those complex interactions that make up a process. Wouldn’t it be nice if you could have them running the plant all the time?
Companies that have implemented successful APC (advanced process Control) projects suggest they’ve done just that and even better. The new drivers for operation center around economic issues such as throughput levels, higher yields, lower energy costs, and generally better financial performance. How does APC operateCONTROL ENGINEERING China版权所有, and how does it deliver on such lofty promises in the real world?
Basic concepts
APC is a term that can include a range of methodologies, including model predictive control (MPC), fuzzy logicwww.cechina.cn, neural networks, and others. The common objective is to find a way to manage complex interactions within a process better than traditional regulatory control. Regulatory control works best when one variable and one actuator are related. However, often moving one actuator affects several variables at the same time. This is where traditional methods lose some effectiveness.
“There are systems that do not run on just regulatory controlwww.cechina.cn,” says Dr. Eduardo Gallestey, ABB global business manager for optimization solutions. “The most cited examples are modern airplanes, and they really need advanced process control tools. But with most industrial practice, companies try to design processes that are stable using regulatory control. I stress the word stablewww.cechina.cn, but it does not mean optimal. You can run the plant with regulatory controlwww.cechina.cn, but you’ll be far from optimum.”
Pete