▲ 4 r/ControlTheory
Seeking advice: Best PLC control strategy for a Quadruple-Tank process? – Engineering Student
Hello, nice to meet you. I'm an electronics student and I've been given this project: I have to physically control the water level in a plant with four tanks (see photo below), not just theoretically.
I've controlled a single tank before, but this is different. The problem is that the pumps are cross-connected: Pump 1 fills tanks 1 and 4, while Pump 2 fills tanks 2 and 3. Basically, if I adjust one pump to fix one level, I'll mess up the other. The details of the setup:
- The diagram follows ISA-5.1 standards.
- I have 4 LITs (Level) and 2 FITs (Flow) sending signals to a PLC.
- I use 2 Pumps driven by Variable Frequency Drives (SZ-01 and SZ-02). It's important to note that the water flow is controlled by adjusting the motor frequency via these VFDs.
- I have the freedom to add and program whatever blocks I want in the PLC :D.
You don't have to do the work for me, but if someone could guide me on which control structure would actually work for this tightly coupled system in a real PLC environment, it would be a huge help. Thanks!
u/PimientoVerde — 4 days ago