600MW级超（超）临界机组切除加热器抽汽的动态响应特性比较

Comparison on dynamic response characteristics of steam extraction cutting at preheater among 600 MW class (ultra) supercritical units

中文关键词: 切除加热器抽汽  燃煤机组  发电功率  动态响应

英文关键词: steam extraction cutting at preheater, coal-fired power unit, power generation, dynamic process

中文摘要:

      切除加热器抽汽可以提高燃煤机组对电网的快速负荷和频率响应能力，研究同一等级不同参数燃煤机组的快速响应特性，对于实际工程应用具有重要意义。基于Dymola软件对600 MW级的三个不同设计参数的燃煤发电机组进行热力系统建模，研究三个机组在切除加热器抽汽后，发电功率的动态响应特性。结果表明，切除加热器抽汽可以快速提升机组发电功率响应电网需求，切除的加热器的抽汽参数越高，发电功率的响应时间越长；抽汽流量越大，负荷变化量越大，负荷平均变化速率越快；采用切除低加或高加方式来提高机组响应能力上，还需要从响应功率、响应时间和响应过程恢复后对回热器影响等三个方面考虑，综合选择合适和可靠的动态快速响应技术。

英文摘要:

      Steam extraction cutting at preheaters in three coal-fired power units have been shown to enhance their rapid load and frequency response capability. In this study, the thermodynamic system of three different 600 MW coal-fired power units, each with distinct design parameters, is modeled using commercial software Dymola. The dynamic response characteristics of power output for each unit are investigated following the steam extraction cutting of the preheater. Research results demonstrate that the preheater cutting leads to a swift enhancement of the unit's power output response to grid demand. Notably, the response time for power output increases as the steam extraction parameters at the preheater are higher. Additionally, as the extraction steam flow rates increase, the load change becomes more significant and the average load change rate accelerates. When conducting preheater extraction cutting methods to enhance the load and frequency response capability of the power plants, it is necessary to consider the effects on the safety and performance at the preheaters among response power, time, and cutting process recovery, and then to select appropriate and reliable dynamic rapid response technologies.