Non-linear PID controller and methods of its setting

Abstract

Article is devoted to the questions of improving work quality of regulators with proportional-integral-differential and proportional-integral laws of controlling technological processes. The quality classical law of regulation can be improved using non-linear control loop for the difference between the set value and the actual value. At a preliminary investigation phase two non-linear functions (polygonal and logarithmic) which can be easily implemented by existing means of regulation of technological processes on production were chosen. Regulators setting was made by means of simulation modelling system and numerical minimization of the modified integral criterion. The studies were conducted in the MatLab. Operation of regulators was examined for a wide class of objects. For optimal adjustments of the linear and non-linear regulation laws the main quality criteria of transient phenomenon (time transient, overshoot, robustness) are defined.