Study On Industrial Boiler Feedwater Control System

The boiler is a necessary power equipment of industry sectors such as generation of electrical energy, oil refinery, chemical industry, papermaking and refinement of sugar and so on. In order to ensuer the production and security, the auto-control is very important. And the boiler water level is an important variable to be controlled. Because the boiler water lever is an important index of industry boiler safety and satabilization. It is important meaning to ensure water level in definite range for increasing quality of steam and reducing wastage of equipment and insuring safety of whole system operation. At present, the mostly method adopts the routine PID control, because of routine PID control parameter is changeless. It is difficuty to adapt the diversied disturb and variational object. The method is not satisfy require and ideality.This article has carried out detailed analysis to the boiler water level's dynamic characteristic and several used control methods, and determines the connection of traditional PID control with the boiler water level's three-variable control. According to summarizing and describing of skill woker's practise experience, it gained non-precise control rules. And then use fuzzy reasoning, automatically adjusts PID parameters to achieve system's optimum control.According to actuality control of boiler water level, putting forward fuzzy PID control rule of parameter adaptability, this paper designs the fuzzy adaptability PID control system on the base of fuzzy reasoning with 2 input and 3 output. This system gets over disadvantage of no precision and difficulty to adjust parameter for using tradition control methods. According to the need of actual control, designs a controller and it is with 8031 centre. In the course of design, detailed exposes every part of the circuit, and carries on software design according to control circuit of the hardware and the need of control. The result indicated that the fuzzy adaptability PID control system is adaptive ability, anti-jamming and strong robustness.