Proportional control can be explained as follows: the change in output of the controller is proportional to the input signal produced by the environmental change (commonly referred to as error) which has been detected by a sensor.
Fig. 8.15. Oscillatory pattern of a simple two-position valve or switch.
Fig. 8.16. Oscillatory pattern of the temperature of a domestic water tank (no water being drawn off) using ON/OFF control of the heating element.
_ Output without control
------Proportional + derivative action
---------Proportional + integral + derivative action
Mathematically it can be expressed by the following equation:
where M = output signal,
M0 = controller output signal when there is no
Was this article helpful?
Discover How To Become Your Own Brew Master, With Brew Your Own Beer. It takes more than a recipe to make a great beer. Just using the right ingredients doesn't mean your beer will taste like it was meant to. Most of the time it’s the way a beer is made and served that makes it either an exceptional beer or one that gets dumped into the nearest flower pot.