In recent years, the proportion of cogeneration units in coal-fired units has increased, and thermal power generation has gradually assumed the heavy responsibility of peak regulation, and the demand for flexibility has increased. Combined heat and power circulatingfluidized bed (CFB) units can use boiler steam-water side and heat network heat storage to improve the rapid variable load capacity of theunit, so a quantitative calculation method for steam-water side heat storage and heat network heat storage of supercritical cogenerationCFB units was proposed. Taking a 350 MW cogeneration CFB unit as an example, the working fluid flow on the steam-water side of theunit and the steam extraction and circulating water of the heat network were analyzed. The heat storage coefficient C and the heat networkheat storage coefficient C were calculated under different load conditions (35% ~90%) by combining the design parameters and historicaloperation data of the unit, and the load response characteristics of the unit and the sustainable time of heat storage utilization were furtheranalyzed. The results show that with the increase of the load of the unit, the heat storage coefficient C of the steam-water side increases,and the C of the steam-water working fluid changes greatly in the high load stage of the unit, while the heat storage coefficient C of theheat network is almost unchanged. The sustainable time of heat storage utilization of the unit is directly proportional to the load of the unitand inversely proportional to the variable load rate of the unit. The sustainable time of heat storage utilization of heat network is greaterthan that of steam and water side, and the heat storage capacity of heat network almost does not change with random group load changes.At the variable load rate of 4% / min, the heat storage utilization of the heat network can last for about 285 s, while the heat storage utilization on the steam side can last for 161.5-249.7 s. The above calculation results can provide theoretical guidance for the deep peak regulation and rapid variable load operation of supercritical cogeneration CFB units.

王唯铧(2000—),男,河北廊坊人,硕士研究生。E-mail:1244036933@qq.com

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WANG Weihua,GAO Mingming,WANG Yongquan,et al.Load response characteristics of 350 MW cogeneration CFB unit[J].Clean Coal Technology,2024,30(9):102-110.