动力工程学报
動力工程學報
동력공정학보
JOURNAL OF POWER ENGINEERING
2012年
7期
542-546
,共5页
直接空冷机组%最佳真空%风机耗功%变工况%经济运行
直接空冷機組%最佳真空%風機耗功%變工況%經濟運行
직접공랭궤조%최가진공%풍궤모공%변공황%경제운행
direct air-cooled unit%optimum vaeuum%fan power eonsumption%variable condition%economic operation
为了提高直接空冷机组运行经济性,以冷端系统的变工况模型为基础,通过计算空冷凝汽器风机送风量增大时空冷机组发电功率与对应风机耗功功率的增量,得到直接空冷机组凝汽器最佳真空的确定方法.根据相似定律确定迎面风速对风机耗功的影响,并通过冷端系统数学模型的分析和简化得到机组背压与发电功率的关系,最终导出了不同环境温度和排汽热负荷下迎面风速对应的最佳真空.根据模型对某330Mw机组在变工况下的最佳真空进行了计算,结果表明:随着排汽量的增加或环境温度的升高,最佳真空及对应的风量都增加;当环境温度高于20℃时,环境温度对最佳真空的影响更加突出.
為瞭提高直接空冷機組運行經濟性,以冷耑繫統的變工況模型為基礎,通過計算空冷凝汽器風機送風量增大時空冷機組髮電功率與對應風機耗功功率的增量,得到直接空冷機組凝汽器最佳真空的確定方法.根據相似定律確定迎麵風速對風機耗功的影響,併通過冷耑繫統數學模型的分析和簡化得到機組揹壓與髮電功率的關繫,最終導齣瞭不同環境溫度和排汽熱負荷下迎麵風速對應的最佳真空.根據模型對某330Mw機組在變工況下的最佳真空進行瞭計算,結果錶明:隨著排汽量的增加或環境溫度的升高,最佳真空及對應的風量都增加;噹環境溫度高于20℃時,環境溫度對最佳真空的影響更加突齣.
위료제고직접공랭궤조운행경제성,이랭단계통적변공황모형위기출,통과계산공냉응기기풍궤송풍량증대시공랭궤조발전공솔여대응풍궤모공공솔적증량,득도직접공랭궤조응기기최가진공적학정방법.근거상사정률학정영면풍속대풍궤모공적영향,병통과랭단계통수학모형적분석화간화득도궤조배압여발전공솔적관계,최종도출료불동배경온도화배기열부하하영면풍속대응적최가진공.근거모형대모330Mw궤조재변공황하적최가진공진행료계산,결과표명:수착배기량적증가혹배경온도적승고,최가진공급대응적풍량도증가;당배경온도고우20℃시,배경온도대최가진공적영향경가돌출.
To improve the thermal economy of direct air-cooled power unit, a determination method for op timum vacuum has been developed by calculating the increment of both the unit power generation and the auxiliary power eonsumption based on the variable condition model for eold end system, at rising supply rate of air for condenser. According to the similarity law, the effect of face velocity on fan power consump- tion is determined firstly, then the influence of baek pressure on unit power generation is obtained by ana- lyzing and simplifying the mathematical model of cold end system, and finally the optimum vacuum corre- sponding to various face velocities is deduced at different ambient temperatures and different exhaust steam heat loads. Calculation results on a 330 MW unit show that both the optimum vacuum and corresponding air velocity increase with rising exhaust steam or ambient temperature; the optimum vacuum is greatly af letted by the ambient temperature, when the temperature gets above 20℃.