RESEARCH ON DRUM WATER LEVEL CONTROL OF MARINE AUXILIARY BOILER BASED ON ADRC

Abstract

The active disturbance rejection control (ADRC) exhibits strong robustness and adaptability in the presence of strong interference of a large class of uncertain systems. In order to better control the water level of the auxiliary boiler drum, this paper applies the ADRC to improve its control precision, robustness and timeliness. Firstly, the change of drum water level in a large oil tanker auxiliary boiler is analyzed and the dynamic equation is established. After the mathematic changes, the dynamic equation is transformed into a two-order system. Aiming at the characteristics of nonlinear, time-varying and strong disturbance of the boiler water level control system in marine auxiliary boiler, studying the ADRC that includes tracking differentiator (TD), extended state observer (ESO), nonlinear feedback (NLSEF) and disturbance compensation of four parts. The establishment of two kinds of two-order ADRC controller to control the drum level. Through the theoretical analysis and simulation experiment test, and comparing with the cascade control strategy, the experimental results show that the active disturbance rejection controller satisfies the steady state response index of the system, and has good timeliness and accuracy to the control of water level of the drum.