基于PLC的锅炉三冲量给水控制系统设计-辽科大本科毕业设计.doc

ater levels can have serious consequences, so strict control of the steam drum water level is necessary. The rapid development of PLC technology has made PLC widely used in process control field and greatly improved the performance of control systems. PLC has become an indispensable equipment in today's automatic control field. This paper introduces the control scheme design, PLC introduction and system software design from several aspects. Starting from analyzing various factors that affect the steam drum water level, the "false water level phenomenon" of the steam drum water level is analyzed in detail, and a three-impulse control scheme for the boiler steam drum water level control system is proposed. This system uses Siemens S7-300 to achieve automatic control of the boiler steam drum water level, and PID parameter tuning is carried out according to the engineering setting method, and simulation research is conducted. From the simulated result curves, it can be seen that the performance indicators of the system have met the requirements. Keywords: PLC; boiler; three-impulse; steam drum water level; PID control.