【摘要】 【目的】深度调峰和快速升负荷下煤耗增加使发电成本增加、调峰收益下降，为探究该过程中发电煤耗的变化规律，为机组深度调峰提供依据。【方法】本文基于Modelica建立了660 MW亚临界机组动态仿真模型，并通过与设计数据及现场数据对比验证了模型的可靠性。在此基础上，开展了深度调峰与快速变负荷工况的仿真实验研究。【结果】研究表明，在20%、25%、30%负荷下的发电煤耗较100%负荷分别增加13.6%、11.1%和9.1%。在降负荷过程中，由于锅炉释放自身蓄能，发电煤耗始终低于相应稳态煤耗。在每分钟1%负荷下降速率下，当负荷降至约52%负荷时，瞬时煤耗较稳态值降低约7.5%。在升负荷过程中，由于锅炉需补充蓄能，煤耗普遍高于稳态工况。当以每分钟1%负荷速率，负荷升至约52.1%负荷时，瞬时煤耗较稳态值高出约11.0%。变负荷速率越快时瞬时煤耗变化越明显，在降负荷过程中，每分钟1%负荷速率下瞬时煤耗最低值为288 g/（kW·h），每分钟2.5%负荷时为256 g/（kW·h）。升负荷过程中每分钟1%负荷速率下瞬时煤耗最高值为344 g/（k W·h），每分钟2.5%负荷时为386 g/（k W·h）；【结论】在稳定运行工况下，机组负荷越低发电煤耗越高。降负荷过程中瞬时发电煤耗降低，升负荷过程中瞬时发电煤耗升高，且变负荷速率越高，煤耗瞬时变化幅度越大，研究结果为新型电力系统下同类机组经济运行提供参考。更多还原

【Abstract】 [Objective]The increase in coal consumption during deep peak shaving and rapid load increase leads to higher power generation costs and reduced peak-shaving revenue. This study investigates the variation patterns of coal consumption rate for power generation under these operating conditions. [Methods]A dynamic simulation model of a 660 MW subcritical coal-fired unit was developed using Modelica. The model’s reliability was verified through comparison with design values and field data. Simulations of deep peak shaving and rapid load change conditions were subsequently performed. [Results]Compared to operation at 100% rated load, the coal consumption rate for power generation increased by 13.6%, 11.1%, and 9.1% at 20.0%, 25%, and 30% rated load, respectively. During load reduction, the release of stored heat from the boiler results in an instantaneous coal consumption rate that remains lower than the corresponding steady-state value. At a load reduction rate of 1% per minute, when the load drops to approximately 52%, the instantaneous coal consumption is about 7.5% lower than the steady-state value. Conversely, during load increase, the need to replenish the boiler’s stored energy leads to an instantaneous coal consumption rate that generally exceeds the steady-state value. At a load increase rate of 1% per minute, when the load rises to approximately 52.1%, the instantaneous coal consumption is about 11.0% higher than the steady-state value. A higher load change rate results in more pronounced variations in instantaneous coal consumption. During load reduction, the minimum instantaneous coal consumption is 288 g/（kW·h） at a rate of 1% per minute, and 256 g/（kW·h） at a rate of 2.5% per minute. During load increase, the maximum instantaneous coal consumption is 344 g/（kW·h） at a rate of 1% per minute, and 386 g/（kW·h） at a rate of 2.5% per minute.[Conclusion]Under static operating conditions, a lower unit load results in a higher coal consumption rate for power generation. Transient coal consumption decreases during load reduction and increases during load increase, with the magnitude of these variations growing as the rate of load change increases. The findings provide a reference for the economic operation of similar units in a power system with high renewable energy penetration.更多还原