Control theory is an interdisciplinary branch of engineering and mathematics that deals with the behavior of dynamical systems. The external input of a system is called the reference. When one or more output variables of a system need to follow a certain reference over time, a controller manipulates the inputs to a system to obtain the desired effect on the output of the system.
The usual objective of a control theory is to calculate solutions for the proper corrective action from the controller that result in system stability, that is, the system will hold the set point and not oscillate around it.
Control theory is a theory that deals with influencing the behavior of dynamical systems. Control theory is an interdisciplinary sub-field of science, which originated in engineering and mathematics, and evolved into use by the social sciences, like psychology, sociology, criminology and in the financial system.
Control systems can be thought of as having four functions; Measure, Compare, Compute, and Correct. These four functions are completed by five elements; Detector, Transducer, Transmitter, Controller, and Final Control Element. The measuring function is completed by the detector, transducer and transmitter. In practical applications these three elements are typically contained in one unit. A standard example is a Resistance thermometer. The compare and compute functions are completed within the controller which may be completed electronically through a Proportional Control, PI Controller, PID Controller, Bistable, Hysteretic control or Programmable logic controller. The correct function is completed with a final control element. The final control element changes an input or output in the control system which affect the manipulated or controlled variable. View More
