TTS20 Three-Tank-System

The laboratory experiment "Three-Tank-System TTS20" includes the technical realization of a nonlinear multi input- multi output system (two inputs, two outputs) with two actuators.

The nonlinear controlled system consists of three plexi-glass cylinders T1, T2 and T3 with the cross-sectional area A which are interconnected in series by two connecting pipes. The liquid (distilled water) leaving T2 is collected in a reservoir from which pumps 1 and 2 supply the tanks T1 and T2. All three tanks are equipped with process pressure transmitters for measuring the level of the liquid. A digital controller controls the flow rate Q1 and Q2 such that the levels in the tanks T1 and T2 can be preassigned independently. The level in tank T3 is always a response, which is uncontrollable. The connecting pipes and the tanks are additionally equipped with manually adjustable valves and outlets for the purpose of simulating clogs as well as leaks.

The documentation of the Three-Tank-System includes sections for assembly and start-up, the technical data, the theoretical background, the mathematical model of the plant as well as guidelines for the practical course with solutions.

The Three-Tank-System TTS20 qualifies for use in research projects in nonlinear control and fault diagnosis. The standard version of the TTS20 already contains a electrical disturbance unit which allows the simulation of eight different faults affecting the sensors, the plant and the actuator. For the three sensors total failures can be simulated by switches while scaling errors can be adjusted by potentiometers. A variation of the actuator amplification can be achieved by attenuating the control signals for the two pumps. The attenuation can be adjusted using potentiometers. The last manipulations simulate two further component failures besides the mentioned clogs and leaks.

Using a prototype of the TTS20, researchers in the department of measurement and control at the University of Duisburg have successfully tested methods of nonlinear decoupling and model based fault diagnosis.

As extension for the laboratory experiment "Three-Tank-System TTS20" the following options are available:

• Option 20-07a Electrical control valve as coupling valve between the tanks with potentiometer output.

• Option 20-07b Electrical control valve as drain valve with potentiometer output.

• Option 20-09 Complete Adapter Box to connect up to six control valves (Opt. 20-07) to a PC.

Technical data are subject to change (Date 9-March-2024)