燃烧控制系统Combustion Control System1．燃烧控制系统的结构1. Combustion control system structure燃烧控制系统为了满足机组负荷变化的需求和保证锅炉安全经济运行，按照协调控制的原则，燃料、送风和引风等子控制系统应根据燃料主控信号(来自燃料主控制系统)进行协调控制。
其总体结构如图4—2所示。
The combustion control system is intended to meet the changing needs of unit load and ensure safe and economic operation of the boiler. In accordance with the principle of coordinated control, sub-control systems for fuel, air supply and induced air should be subject to coordination and control according to the fuel master signal (from the fuel master control system). The overall structure is as shown in Figure 4-2.图4—3燃烧控制系统的总体示意图Figure 4-3 Overall Schematic Map of Combustion Control System 机炉主控制器将送出锅炉主控信号(燃烧率信号)，再分别下达到燃料、送风、引风子系统中去。
对于直吹式制粉方式，通过调节给煤机转速和一次风流量来改变锅炉的燃料量，通过调节送风量和引风量来保证锅安全和经济燃烧。
The boiler master controller will issue a boiler master control signal (combustion rate signal) and send it to the fuel, air supply and induced air sub-systems. In view of the direct-fired pulverizing method, the boiler fuel flow is changed by adjusting the coal feeder speed and the primary air flow, while the boiler safety and economic combustion is ensured by adjusting the air output and air input.由图4—3可见，当机组负荷变化需要改变燃料量时，由负荷控制系统中的燃料主控系统根据锅炉负荷指令产生燃煤负荷指令和风量指令，其中燃煤负荷指令送往燃料控制系统(包括磨煤机料位/给煤机转速控制、燃油控制、一次风压力控制、携带风控制和旁路风控制系统等)、送风控制系统(包括送风机压力控制、燃烧风控制系统等)和引风控制系统，使燃料、送风、引风等共同适应负荷变化，保证锅炉安全经济运行。
Figure 4-3 shows that, when the fuel flow needs to be changed in case of changes in the unit load, the fuel master control system in the load control system will generate a fire coal load demand and an air flow demand according to the boiler load demand. The fire coal load demand is sent to the fuel control system (including coal mill level / coal feeder speed control, fuel control, primary air pressure control, carrying air control and bypass air control system, etc.), the supply air control system (including air supply fan pressure control, combustion air control system, etc.) and the induced air control system. This allows the fuel, supply air, induced air, etc. to commonly adapt to changes in load, thereby ensuring safe and economic operation of the boiler.可以看出燃烧控制系统是一个典型的多变量、多级耦合的控制系统。
整个燃烧控制系统中的风、煤各子系统都串接在协调控制系统的下级，协调控制系统输出的锅炉负荷指令统一指挥风、煤各子系统的协调动作。
It can be seen that the combustion control system is a typical multi-variable control system of multi-stage coupling. The air and coal subsystems in the entire combustion control system are cascaded in the lower level of the coordinated control system. The boiler load demand input by the coordinated control system gives unified command to the coordinated action of air and coal subsystems.燃料主控系统是串接在协调控制系统下的一个“比值一串级”控制系统，燃料主控制系统的输出指令是携带风控制系统的给定值，携带风调节器根据该指令与携带风实际风量的偏差信号控制磨煤机入口管路的风门开度，以调整一次风量，从而适应锅炉负荷所需的煤粉量。
为了保证稳定地供应所需煤粉量，就必须稳定一次风压，为此通过一次风控制系统控制两台一次风机的入口导向挡板开度，以保证一次风压稳定。
The fuel master control system is a “ratio-cascade” control system cascaded to the coordinated control system. The output demand of the fuel master control system is a given value of the carrying air control system. The carrying air regulator controls the throttle opening of the coal mill inlet line according to the deviation signal between this demand the actual carrying air flow, so as to adjust the primary air flow and accommodate the amount of pulverized coal required by the boiler load. In order to ensure stable supply of pulverized coal required, the primary air pressure must be stable. Therefore, the primary air control system controls the opening of the inlet guide baffle of two primary air fans so as to ensure the stability of the primary air pressure.锅炉送风量控制系统是串接在燃料主控制系统下的一个具有氧量校正的比值控制系统。
保持进入锅炉炉膛的实际总风量与锅炉燃料量相适应，从而间接保证风煤比最佳。
在具体实施过程中，该系统又通过送风压力控制系统、燃烧风(包括辅助风、燃尽风、夹心风等)控制系统以及气一汽温度控制系统等实现。
The boiler air output control system is a ratio control system which is cascaded to the fuel master control system and is capable of oxygen correction. The actual total flow entering the boiler furnace should be maintained appropriate for the boiler fuel flow, so as to indirectly ensure the optical air-coal ratio. In the specific implementation process, the system is achieved through the supply air pressure control system, the combustion air (including auxiliary air, over fire air, sandwich air, etc.) control system, and the gas-steam temperature control system.炉膛负压是通过调整两台引风机的静叶片来改变烟气量，以维持炉膛压力为设定值。
为了使引风控制不滞后于送风控制，在引风控制系统中采用了具有风量指令微分信号前馈作用的单回路定值调节系统。
The furnace negative pressure changes the volume of flue gas by adjusting the static blade of the two induced draft fans, so as to maintain the set value of the furnace pressure. To ensure that induced air control does not fall behind supply air control, the induced air control system employs a single-loop fixed value regulating system capable of differential single feedforward action of air flow demand.综上所述，燃烧控制系统必须保证燃料是与空气量的配合，又必须保证引风和送风的配合。