Open Loop Tuning

Introduction

This short simulation has been set up for the user to practise tuning a controller using the Zeiglar Nichols Open Loop Response Method. It assumes that the user has covered the relevent material from Module 2-2 in the HyperCourse.

There are five parts to this exercise:

Look at the open loop response
Analysis of the open loop response
Evaluate controller parameters
Compare with actual values
Run process with control

Look at Open Loop Response

The first stage in the procedure is to look at the open loop response for the process in the graph below:

The change in u (the input variable) was : %

Analysis of Open Loop Response

The second stage is to enter the following values:

Change in y? Dead Time? Time Constant?

Evaluate Control Parameters

The next stage is using the above values to fill in the following table:

Controller Type	Gain	Reset	Derivative
P	(Ts ) / (Td )	-	-
PI	(0.9 Ts ) / (Td )	3.3 Td	-
PID	(1.2 Ts ) / (Td )	2.0 Td	0.5 Td

Controller Type	Gain	Reset Time
Proportional
Proportional Integral

Comparison With Actual Values

Once you have entered your values, please click here to find out how close you are to the actual answers:

Controller Type	Gain	Reset Time	How Close?
Proportional
Proportional Integral

Run Process With Control

Finally it is possible to try out the above values in the simulation below and hence do some fine tuning to find the optimum values.

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