Lesson Summary

PID Control

1.ON-OFF Control

While applying ON-OFF control at a set value of 0% to 100% of the water level with the proportional gain set to its maximum value, you can check and learn its hunting operation.

2.PID Parameters

While applying an optimal tuning method widely known as "Critical Sensitivity method" proposed by Ziegler-Nichgols, you can learn how to determine the respective PID parameters for each and every one of P-Control, PI-Control and PID-Control.

3.P Control

By setting the "Pb" value (proportional band) sought out in the section 2 above, you can check that an offset is produced. While further changing the "Pb" value, you can learn the effects of P control.

4.PI Control

By setting the "Pb" value (proportional band) and "Ti" value (integral time) sought out in the section 2 above, you can check that an offset is eliminated.

5.PID Control

By setting the "Pb" value (proportional band), "Ti" value (integral time) and "Td" value (derivative time) sought out in the section 2 above as well as giving a disturbance of pump power OFF for several seconds, you can check how the setting or non-setting of "Td" value affects to the convergence curve of the control.

Fuzzy Control

1.ON-OFF Control

You can learn how to apply ON-OFF control to the pump using Fuzzy position-type control with 1 input and 1 output.

2.Position-type Control

While applying Fuzzy position-type control with 1 input, 1 output and 3 rules, you can learn how to control the water level as good as the human rough tuning.

3.Position-type + Speed-type Control

While applying Fuzzy position-type and speed-type control with 2 inputs, 2 outputs and 5 rules as well as monitoring the offset, you can learn how to control the water level as good as the human fine tuning. While giving a disturbance of pump power OFF for several seconds in the same manner with that for PID control, you can learn how to cope with the problem.

4.Advanced Application (Control Comparison)

While applying the preset values, you can learn the rules how to prevent overshooting and undershooting with the step-formed set values. Since only 1 pattern of PID parameters is available, PID control can not prevent both overshooting and undershooting at the same time.

 (C) 2004 ADWIN Corp.