以某电厂650 MW超临界机组为研究对象，针对机组传统供热改造后“以热定电”调峰灵活性较差的运行问题，提出了“低压缸零出力技术”的工作原理和提高机组热电解耦能力的改造方案，并分析了“低压缸零出力技术”改造后的灵活性调峰能力及经济性。结果表明：额定工况发电负荷由改造前的458.6 MW降至353.3 MW；额定工况供热负荷由改造前的540.6 MW增加至821.95 MW；额定工况发电煤耗由改造前的238.2 g/（kW·h）降至201.7 g/（kW·h），可大幅提高机组的灵活性调峰能力和供热能力，经济效益显著。

In this paper，the 650 MW supercritical unit in a power plant is studied.In view of the operation problem of poor flexibility of “determining electricity by heat” after transformation of the traditional heat supply system of the unit，the working principle and reconstruction scheme of “zero output technology of lowpressure cylinder” are put forward，the thermoselectricity decoupling capacity of unit is improved，and the flexible peakload regulation capability and economy are analyzed for the transformation of “zero output technology of lowpressure cylinder”．The results show that：the generation load under rated condition decreases from 458.6 MW before the transformation to 353.3 MW．The heating load under rated condition increases from 540.6 MW before the transformation to 821.95 MW．The coal consumption for power generation under rated condition decreases from 238.2 g/（kW·h） before the transformation to 201.7 g/（kW·h）．This shows that after the transformation of “zero output technology of lowpressure cylinder”，the flexible peakload regulation capability and heating capacity of the unit have been greatly improved，and the economic benefit is remarkable．

TM621