中文摘要：

目前在所有电厂中普遍采用给水回热加热系统来提高机组效率，且机组效率随回热级数的增加而提高，但受汽轮机结构等因素的制约，现有机组一般采用7—9级回热。本文研究在不改变汽轮机结构的情况下，采用喷射式热泵技术增加回热级数，从而提高机组效率。通过对某660MW机组进行计算，结果表明采用喷射式热泵可使该机组热效率提高0．13％，发电标准煤耗率下降0．35g／kWh，每年节省标准煤1617．6t以上，机组热经济性显著提高。

英文摘要：

Nowadays all power plants are using feedwater regenerative heating systems to im- prove the turbine unit efficiency, and the economic efficiency increases along with the number of regenerative heating system, however at present all fossil power plants apply 7-9 heaters owing to the limitation of turbine structure. The present paper studies how to increase the number of heaters thus to improve the turbine unit efficiency, using stream ejector pump without changing the structure of turbine. Through the calculation of a 660 MW unit, the paper indicate that when applying ejector pump into regenerative heating system the turbine unit efficiency will in- crease by 0.13%, standard coal consumption rate will decrease by 0.35 g/kWh and each year can save standard coal about 1617.6 ton, which is remarkable in improving the unit thermal economic efficiency.