A self-adjusting PID control and its application in paper-making enterprises

Most of PID controllers could not work well due to its parameters, so a PID parameters´ self-adjusting method, modified A-H arithmetic, was introduced. This method can adjust the PID parameters very well. It adjusts PID controller´s parameters by cross point of object´s Nyquist curve and negative imaginary axis. It has good identification result to time-delay process. We used it in evaporation procedure´s control successfully and effectively. The result shows that this parameters´ adjusting method of control system can work in an optimal state and has practical significance.