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Cascade control system

The lag between upset and response directly impacts a system’s performance along with the performance of other processes with which it interacts.  Fortunately, there are a variety of approaches available that leverage the PID’s capabilities.  These approaches improve a system’s ability to reject the negative impact of disturbances.  Cascade Control is among them.
Cascade Control is an advanced application of the PID that can improve control of systems that are subject to significant lag.  Since such systems are slow to respond to disturbances their performance can suffer with each upset.  The Cascade architecture can be applied effectively to such sluggish processes when a related and faster responding loop is available.  When applied in concert the faster loop serves as an early warning mechanism that buffers the impact on its slower counterpart, allowing for smoother control and enhanced performance.
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