Controlling/Regulating
Assignment
When controlling, the controlling device attempts, through one or more adjustment values, to influence the source value. When regulating, the regulating device constantly compares the required- with the given values, thus attempting, by changing the soürce values, to bring the required- and the given value into harmony with each other.
Actuator
This receives it's information from the controlling- or the regulating device. It is installed at the beginning of the control- or the regulating range and influences the regulation range of the mass- and/or energy flow.
Control range (regulation range)
This is the total range, in which an actuator can directly engage in the mass- and/or energy flow, and also the range in which an interference value could have an influence on it. In addition, there is the range where the changes influenced by the interference values are adjusted, i.e., back to the direction of the changes corrected by the actuator.
Interference value
The name is a little misleading, the interference value has nothing to do with a possible mal
function of a regulation. It is simply a method of expressing an unknown parameter, which changes the original condition of the regulation. It is important that the regulation reacts to the interference value in a suitable manner. The interference value can concern both deliberately- and unintentionally influenced values. In this sense, any influencing of the mass- and/or energy flow outside of the actuator, can be described as an interference value.
Example
Take for example, the cruise control regulation. There is a given value which the driver determines, of course, this is also changeable, it is also called the reference variable. If all the conditions remain constant, the speed can be reached and maintained, by means of placing a certain amount of adjustable strain on the engine (e.g., the throttle-flap position). Should an interference variable occur, e.g., in the shape of a slope, the engine strain must be corrected, also when a change in the regulated speed (reference variable) is carried out. 05/11
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