经研究，在取消脱硫增压风机时，若锅炉负荷低于75％THA工况及以下，由于引风机的运行工况落在理论失速线以内，理论上是运行的“禁区”；在100%THA工况时，由于离理论失速线很近，引风机运行没有安全裕量，风机稍有偏离运行工况的情况，引风机就可能发生喘振；在100％THA～100％BMCR工况时，引风机已经运行在TB点或者超过TB点了，就是引风机能力工况已经用尽，引风机风量调节裕度很小，随着烟气量的增大，引风机再次进入失速区，效率反而降低。从节能降耗和安全角度考虑，采用引风机与脱硫增压风机合二为一模式下重新对风机进行选型，采用技术经济性更优的双级动叶可调轴流风机是满足风机合二为一要求的。为了响应国家的节能减排号召，取消脱硫增压风机，使机组在一定负荷下，充分利用改造后引风机增容的裕量，来克服烟气系统以及脱硫系统的全部阻力，以达到节能降耗的目的。

It has been proved that if the desulfurization booster fan is canceled, the working point of IDE(induced draft fan)wil fal into the theory stal line, which is caled the forbidden zone, if the boiler load is under 75%THA. When the boiler load is at 100% THA, the IDF wil lost it’s safety margin for it’ s working point is near the theory stal line, and the IDE wil be apt to surge; When the load is between 100% THA and 100% BMCR, the THA wil work on or over TB point, which means that the THA has ran out it’s working capacity and the regulating margin is very narrow. With the increase of the smoke, the THA wil fals into the stal zone again and cause lower efficiency. In consideration of energy saving and safety, the fan should be reselected under the integration mode of the THA and the desulfurization booster fan. Technical and economic analysis revealed that the variable pitch axial fan of double blade is better and feasible.

为了节能和提高能源利用率，锅炉风烟系统采用了3台电动引风机，从而出现了常规双引风机的平衡偏置控制策略不适用于炉膛压力控制，且无法实现3台引风机之间的平衡控制的问题。对此，通过在Ovation DCS上开发IDFBALANCER宏模块，很好地解决了3台引风机间的平衡控制问题，并且提高了在改变自动控制方式的引风机数量时，炉膛压力调节回路的自适应能力。

To enhance the energy utilization efficiency,three motor-driven induced-draft fans (IDF)are ap-plied,causing problem taht the balance bias control strategy of the conventional double-IDF is not applica-ble to furnace pressure control.Moreover,balance control of the three IDFs can not be realized.Thus,by developing macro module IDFBALANCER in Ovtaion DCS,the balance control problem among the three IDFs was well solved,and the control loop''s adaptive ability with different auto IDF''s numbers was en-hanced.

经过对480 t/h循环流化床锅炉进行引风机出力试验和锅炉本体烟道、除尘器以及脱硫系统等阻力分析后,认为取消炉外湿法脱硫增压风机后引风机可以满足锅炉最大蒸发量工况时的负荷需要,并制定技术改造方案和运行措施后组织实施。根据2号炉外脱硫系统拆除增压风机后运行情况,表明锅炉在最大蒸发量工况运行时引风机仍留有裕量。

Based on the analysis of output test of CFB boiler induced fan and resistance analysis of the flue,dust collector and desulfurization system,it is concluded that without the desulphurization booster fan, the induced fan can meet the load demand when the boiler is on maximum amount of evaporation. Implementation was carried out based on technical transformation scheme and operation measures. A case study on the desulfuiztion system of No.2 unit on which the booster fan was cancelled proved that there was extra load when the boiler is on maximum amount of evaporation,and the reliability and economical efficiency of the unit was thus improved.

为彻底解决锅炉引风机轴承温度高的问题，设计了一套大型风机轴承分配式环形冷却装置，可以在不停风机的情况下对风机轴承进行冷却，大大减少了停炉次数。

To completely solve the problem of high temperature in the bearings of draft fan for boiler, a distribution-type circular cooling device for the bearings of large fan was designed, which can cool the fan bearings during constant running of the fan, greatly reduc-ing furnace shutdowns.

介绍了燃煤电站锅炉引风机的不同型式，并就轴流式风机和离心式风机在节能、可靠性、耐磨性方面做了详细的对比，得出动叶可调轴流式风机在各个指标上有较大优势。

To introduce the different types of coal fired power plant boiler ID fans, and a detailed comparison is made out for axial flow fans and centrifual fans in regards to energy saving, reliability, and abrasion. The result shows the obvious advantages of variable pitch axial flow fans in different indexes.