Two tank mixing + heating system (2): advanced cascade feedforward ratio control case study

Antonio Sala, UPV

Difficulty: **** ,       Relevance: ,      Duration: 21:45

*Enlace a Spanish version

Summary:

This video continues the case study discussed in the video [estrx2aEN] of level, temperature, and concentration control in a two-tank liquid system. In said video, the problem was stated, and the multi-loop proposal from common-sense argumentations (justified with calculations in the video [mzrgaEN]) was reviewed as the most basic option that, if it worked, would not require worrying about anything else.

Assuming that it doesn’t work well and that additional instrumentation is acquired, as depicted in a schematic of the process, this video proposes to use:

• Extra sensor cascade control for inlet flow control (and also in temperature loop),

• Feedforward with outlet flow sensor,

• Extra actuator cascade control to take advantage of two heating elements in temperature control,

• Ratio control for the concentration loop

• Decoupling to reduce the effect of level control on temperature.

With this, a final structure is designed: it uses 7 sensors and 4 actuators to control 3 primary references.

The video [mzratdcEN1] addresses an optional discussion on the relationships between inverse decoupling, ratio control, and direct decoupling. In any case, the discussion is optional, specialized, and it is not necessary to understand what is proposed here.

*Link to my [ whole collection] of videos in English. Link to larger [ Colección completa] in Spanish.