Solutions for Tutorial 9

McMaster UniversitySolutions for Tutorial 9Cascade ControlCascade control can dramatically improve the performance of feedback control systems,when it is designed and implemented correctly. This tutorial provides exercises on theproper design of cascade control. Recall that the cascade design criteria provide thebasis for the proper selection of cascade control; these criteria should be used during thistutorial.9.1 Furnace coil outlet temperature control in Figure 9.1.a. Determine whether the cascade control is possible as designed. If not, makeappropriate changes to achieve cascade control.FCPCTCFCFigure 9.1 Fired heater process with simplified control.04/09/01 Copyright © 2000 by Marlin and Yip 1McMaster Universitya. Yes, cascade is possible because the design satisfies the cascade design criteria.1. Control without cascade is not N/A for determining if cascade is possible.acceptable. But, it is important to determine whencascade is recommended!2. Secondary variable is measured Yes3. Indicates a key disturbance see responses for each disturbance4. Influenced by the manipulated Yesvalve5. Secondary dynamics faster Yesb. For each of the following disturbances, determine whether the cascade design,after modifications in part a (if needed), will perform better, the same, or worsethan single loop feedback (TC→ valve).1) fuel supply pressure: Cascade is better. The flow controller will compensate for thedisturbance. Whether the secondary ...