直接空冷机组最佳真空特性与最佳风机转速研究

Study on Optimal Vacuum Characteristic and Optimal Fan Speed of a Direct Air-cooling Unit

以某600 MW直接空冷机组为研究对象,分析了机组微增功率、轴流风机群微增耗功与风机转速之间的关系,并确定了在环境温度、环境风速和机组负荷同时变化时机组最佳空冷轴流风机转速和最佳排汽压力。结果表明:环境温度变化对机组最佳排汽压力的影响很大,当环境温度超过15℃时,该机组的最佳排汽压力迅速增加;环境风横掠对空冷单元进风量的影响比纵掠大;夏季负荷高时维持相对较高的排汽压力有利于机组经济运行,而冬季适当调整风机转速使排汽压力维持在较低值更利于机组节能。

Based on a 600 MW direct air-cooling unit, the relationship between the micro-power of steam turbine and the fan speed is analyzed, and the optimal air-cooling fan speed and the optimal exhaust pressure when environmental temperature, environmental wind speed and the load change simultaneously are determined. The results show that when the environmental temperature exceeds 15 ℃, the optimal exhaust pressure of steam turbine increases rapidly. The influence of environmental wind cross-sliding on air-cooled unit is greater than that of longitudinal-sliding. Maintaining high exhaust pressure when the unit is under high load is beneficial to economic operation in summer, while adjusting the speed of fan and maintaining the exhaust pressure at a lower value are more conducive to energy saving in winter.