In all.
Today I will discuss about tank level control system using PID controller.
So for that purpose I just open a already given example inside the knee example finders.
I just go over there.
Then I just type a keyword PID over here.
As you see list of codes are there.
I just select simulation tank level control.
I just open it.
As you see over here, it is created by an AI.
So I just explain you what is inside this and what is inside the program.
So over here, as you see in the tank level control system, basically this example demonstrates a process
simulation for the tank level.
Inside this we have different type of errors or disturbances like noise valve deadband lag, dead time,
a level controller adjust inlet flow.
And we have also a drain valve we can manually on off it.
So in this particular program we just insert a PID controller that can be manually controlled or automatically
controlled.
We just need to check how it tracks the final set point.
Okay.
So over here there are some symbols.
Let's say a T over here stands for level transmitter on the field.
And 101 is the loop count L I, c stands for level controller at the control room again 101 is your
loop count L c V is your level control valve.
And over here H V stands for hand control valve on the field.
And 102 is your loop count.
So I just go to the front panel right now.
Also I'm in front panel.
I just change the type of operation.
As you see over here, we have a symbol of tank and all the valves like level controller and control
valve are there.
And over here we have a PID parameters initially.
We just set it to auto mode.
Okay.
So we just in the starting, we just put some set point over here.
You can change this set point according to this the inlet flow this inlet flow will be controlled using
this PID controller.
And over here this is the drainage we just on off it so that it will empty the tank.
Over here we have a flow sensor and the process chart we just show over here.
So right now I just show you the front panel part.
Let's run it when you just run it.
Initially the set point is around 76.4706.
As you see over here.
Different colors.
Process variable blue color.
This one set point is red one constant.
It is not changing.
And the controller output it is changing now okay this is right now it just want to track the output
okay.
So now process variable and controller set point are nearly same as you see.
And the controller output you just check over here okay.
And over here you just see the inlet flow inside the tank.
Then you just change the set point.
Let's check what happened.
There is a change.
If it is not clearly visible, I just make it.
I mean, I just changed the style.
Basically, I want to increase the width.
So it is clearly visible to you all.
As you see right now, I just again run it.
When it just reached the set point.
When set point and process variable are nearly same, then controller output changes as you see over
here.
This is the controller output green one.
So right now it just maintain around 51.634.
So I just change the set point as you see right now.
Again when it is near by again controller change its output.
Otherwise it is maximum.
And over here you can find out different parameters.
Proportional parameter.
Integral parameter and derivative parameter p I'd.
These are three parameters p I'd.
Okay.
So you just from here right now I just want to change this LCD.
It is not allowing me to change it because it is in automatic mode.
So right now I just hope on brain function.
Also, as you see right now it just decrease the value.
Right now automatic on mode is on.
I just show you in the manual mode.
Also, what is the function of this brain function.
Because it is in automatic mode.
According to this it will just change the value of these PID parameters.
Let's say I want to just decrease the set point.
PID parameters are over here.
And this is level control valve.
How much?
It is open.
As you see over here.
So if you just increase this value, you just check.
What happened over here as you see.
Okay.
So basically to tune the P I'd, I already made some videos uh, to tune second order system.
If the transfer function is of second order you just go through Ziegler-nichols method.
There is a set of rules.
You just need to find out the ultimate gain, then ultimate period.
According to that, you just need to find out these values proportional value, integral value and derivative
value.
And then it will just automatically approach where system.
Right now I just again make it to let's say ten.
And it is let's say one.
What happened.
Basically, the controlling in this process mainly depends on this controller, this PID controller.
Okay, so I just stop it and I just show you the code.
Also just press control E over here.
As you see this one is your PID controller.
I just press control H, select it.
This is your P I'd y loop not PD control.
This is your y loop okay.
This is your PID controller.
PID advanced controller.
It is inside the controller simulation.
Just go to control and simulation PID.
Over here you can find out different PID controllers.
Okay.
This is your pi d.
This is your PID advanced.
Pretty advanced auto tuning for the temperature.
As you see, there are different parameters.
This is PID lead lag compensator.
Okay.
So I just show you this is your feedback controller and this is your valve.
As you see this one is just a symbol.
And this symbol is placed over a Boolean control indicator.
This is our indicator.
This is a control okay.
This is your set point.
So over here and this is your plant I just show you what is inside the plant system.
Just go control E again.
This is your while loop.
And over here we just put some parameters for the process.
As you see initial value of process variable static gain.
Lag dead time load deadband sensor noise plant plant noise.
All these are added inside the plant okay.
And this is your transportation delay.
As you see there is a delay.
There is a sine wave and there are two sine wave.
One is blue color, one is red color orange color.
And the phase difference is there between these two.
And this is your lead lag compensator okay.
And this is your PID timing estimator.
Using these functions you just develop your own PID controller for tank level control system for speed
control of DC motor.
Any application in the industry mainly these type of controllers are used that is known as PID controller
because the cost is very less and easy to implement.
Okay, so I just go to our system when we just make it to manual mode.
So right now I just put it to manual mode.
Right now the parameters are not right because you just find out the parameter value using trial and
error method based on trial and error method, or using Ziegler-nichols method.
Okay, because Ziegler-nichols gives a set of algorithm using which you can find out these parameter
values so your process variable easily track your state set point.
Right now there is a delay because the PID values are not appropriate earlier.
The values are okay, we just change the PID values.
So let's increase this.
Let's check what happened.
You can also say check different values like rise time, delay time, settling time, different values.
I just show you from where you can find out.
Just go over here, go to the control and simulation parameter in the simulation or here in the container.
Not uh, over here.
Nonlinear.
This one is the PID controller.
Over here we have the delay.
And there are different symbols like step signal, pulse, signal, using which you want to test your
system, and the function that I want to check over here, this one.
This is the parametric time response function.
It will give you rise time delay time settling time I just show you.
Right now it is just adding, let's say just go as you see over here.
It will show you rise time, peak time, settling time, overshoot, steady state gain, peak value,
different values.
It will show you okay.
So right now this is all about the tank level control system.
You can.
Check any example inside the LabVIEW example finder.
And this is for the tank level control system using automatic PID control system.
Okay.
Thank.