火电厂单元制循环水系统离散优化模型及其应用

对水量不连续变化的单元制循环水系统提出了一种离散优化模型，该模型以等效益点迭代计算来决定泵组切换时的临界工况。以黄台电厂7号机组为例，利用本模型对循环水系统进行了优化运行研究，确定了机组在不同季节、不同负荷最经济的循环水泵运行编组方式。效益分析表明，对于300MW机组，循环水系统离散优化可使电厂标准煤耗降低0．5～0．7g/(kWh)。文中根据热力试验数据，总结出凝汽器传热系数的一个经验公式，可供同类机组参考。

A Discrete Optimized Model for the Monobloc Configured Circulating Water System of a Thermal Power Plant and Its applications

A discrete optimized model was proposed for a monobloc configured circulating water system featuring non-continuous change of water flow rate. By conducting iterative calculations of equivalent profit points the model can determine the critical operating conditions at the juncture of switch-over of circulating-water pumps. With the power unit No.7 of the Huangtai Power Station serving as an example the present model was used to study operation optimization in order to determine the most economical grouping-mode of operation for the circulating water pumps at different seasons and at various loads of the power unit. A profit analysis indicates that for a 300 MW power unit through the introduction of discrete optimization for a circulating water system it is possible to achieve a reduction of coal consumption by 0.5 - 0.7 g (kWh). On the basis of thermodynamic test data an empiric formula is determined for the heat transfer factor of a steam condenser, which can serve as a guide for other similar units.