I have questions regarding proportional control and ratio control
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This post was last edited by *aoyuhao on 2009-11-17 at 17:58. I went for an interview yesterday, and the interviewer asked me a control-related question. Ask what proportional control is I replied that it was control in which the output is proportional to the deviation from the setpoint, but the interviewer said it wasn’t. The interviewer said that, for example, requiring the traffic volume of A to remain at a certain ratio to that of B, and when there is a change in B’s traffic volume, demanding that A’s traffic volume change rapidly and accurately to maintain this ratio between the two – this is what is known as proportional control. I went back and reviewed relevant books and found that the interviewer was referring to ratio control. Dear sea friends, I’m not quite sure whether what is referred to in books as maintaining a certain ratio actually means proportional control in practical engineering applications
Proportional control is relevant to regulators; as the original poster mentioned, it is a control principle in which the change in the regulator’s output is proportional to the deviation of the parameter being controlled, and this is known as the proportional control law. Proportional control applies to control schemes; a control system in which two or more parameters (such as flow rates) maintain a specified proportional relationship is called a proportional control system. Although the concept is clear, in practical applications these two types of adjustment are often confused, even among experienced instrument technicians. Literally speaking, there is little difference between the two. The key is that the interviewer is asking questions related to control; therefore, you should follow his line of thinking. If you encounter similar confusing questions again, it’s best to answer both options and clarify the difference between a regulator and a control scheme. During the initial training on instruments, many people encountered such problems; since no professionals were available to correct them, those misunderstandings developed into what your interviewer understood.
2# zccchunchen Thank you!