*Enlace a Spanish version
Materials: [ TwoActuatorsSummaryENG.pdf]
This video continues the discussion on strategies for control structures with 1
controlled and 2 manipulated variables. The discussion was started on video
[
There were two main divisions of strategies to solve the problem: those with only one controller in operation and those where a secondary reference is generated, and there are two active controllers.
The first three minutes of the video review strategies with an active controller:
load balancing, split range, and override; These strategies were discussed in detail
in the video [
Continuation of this exposition, here strategies with a secondary reference are explained. The proposed ones are:
cascade control with extra actuator, where the secondary reference is actually an operating point of one of the manipulated variables.
gradual control where, if an intermediate sensor is available, heating, neutralization, etc., can be considered to be carried out by stages, with a secondary reference for that intermediate sensor, that a kind of multiloop control should maintain.
double cascade control, where if there is an extra actuator and also an extra sensor, then the reference for the intermediate ‘gradual’ sensor is generated by the master ‘extra actuator cascade’ structure.
These cascade structures work best (ease of tuning) when there is ‘time-scale separation’, whereas the structures in the first video work best when both manipulated variables have comparable bandwidths, similar dynamics.
*Link to my [ whole collection] of videos in English. Link to larger [ Colección completa] in Spanish.