铁岭电厂#4机组磨煤机控制系统设计大学学位论文.doc

摘 要 300MW机组一次风控制系统及磨煤机出口温度设计主要由燃烧控制系统进行控制，它是保证锅炉运行的基本系统。 燃烧控制系统主要由三个子系统组成：燃料控制系统、送风控制系统和引风控制系统。燃烧控制系统的基本任务是及时响应单元机组主控系统发来的锅炉指令（BD），去改变进入锅炉的燃料量和送风量，同时为了保证炉膛负压，及时改变锅炉的引风量，以保证机组的能量供需平衡。 一次风是用来在制粉系统中输送煤粉到炉膛燃烧的。一次风由一次风机出来分成两路。一路通过空气预热器加热为一次热风，另一路不经过空气预热器为一次冷风，两路风分别经过调节挡板后混合至适当温度，进入磨煤机。磨煤机出口的煤粉由一次风输出，经过制粉系统管路，分别送到炉膛四角的该磨煤机层的4个煤粉喷嘴后，吹入炉膛。正常运行时，一次风总风量由CCS通过调节一次风机动叶开度及热风再循环门开度来实现。 锅炉二次风除由风量控制外，从炉前风箱进入炉膛还要通过风箱控制挡板。各层风室（八层）均设有风室挡板，风室挡板开度控制为层控制，即同一层的四个执行器同步动作。此系统的作用是合理分配燃烧器各层喷嘴之间的配风，而不是调节总风量。根据各部分风所起的作用，二次风又分为辅助风、燃料风和燃尽风。它们分别采用不同的方式控制。 关键词：燃烧控制系统　一次风　磨煤机 Abstract 300MW units Primary air, Secondary air control system design control systems primarily by the burning of control,it is essential to ensure that the boiler operation system. Combustion control system is mainly composed of three subsystems : the fuel control systems, control systems and fans from the air control systems. Combustion control system is a timely response to the basic tasks of system modules were made to control the boilers instructions (BD), to change the volume of fuel into the boiler and enter volume, and to ensure that chamber pressure and timely change from the air of boilers to ensure energy supply and demand were balanced. [16] In primary air milling system is used to transport Coal powder to combustion chamber. primary air from an air-compressors is divided into two routes out. All through the air preheat devices for heating a sirocco, another road without air preheat devices for a bone-chilling, respectively, after adjusting damper after two loads mixed to the appropriate temperature and entered Pulverizer exports by primary air Coal powder export pipeline system after milling, respectively sent to the chamber .4 Pulverizer level 4 Coal powder nozzles, blown burner. Normal operation, a total amount of air from the air-CCS through adjust Primary air fan open degrees and the secondary air opened the door for recycling to achieve. Secondary air major disturbances mixed with the oxygen and C