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00:03
@SambuddhaMookherji Mmk... So it's a PI controller, and not PID?
You need a lot of information to turn a psi setpoint into something useful -- heat exchange doesn't really care about the pressure of the cooling water; you need to know the flowrate.
Do you have the response function for the cooling flow as a function of the pressure setpoint?
@SambuddhaMookherji No... if i read the problem right, the step change is in an uncontrolled parameter: the temperature of the incoming cooling water
So, in order to provide the same rate of cooling, the flowrate of the cooling water will have to increase.
Very complex system response here.
 
2 hours later…
01:46
@hBy2Py Its just a 2 mark problem in the question paper i was solving.. And yes its a PI controller. So how do calculate the error step change ?? This is where I am having the problem..

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