针对现阶段热电联产机组供热期调峰能力不足的问题，以某350 MW超临界燃煤机组为案例，介绍了其高低压旁路供热改造方案，并以改造后机组的实际运行数据为基础，对改造前后机组的运行特性和调峰能力进行了详细的对比分析。结果表明：案例机组进行高低压旁路供热改造后，在保证机组供热期热负荷和热段再热蒸汽流速不超限的情况下，机组电负荷调峰下限可由原来的230.9 MW降至161.4 MW，降低30.1%；当案例机组两个中压调节汽门关至42%时，机组电负荷调峰下限可进一步降至140.8 MW；旁路供热蒸汽量占比可由原来的56.3%提高至61.9%，提高5.6%，机组的调峰能力得到进一步提高

In view of the problem of insufficient peak shaving capacity during the heating period of the cogeneration unit at current stage, the reformation scheme of HPLP bypass system combining with heating in a 350 MW supercritical coalfired unit was introduced. Based on the actual operation data of the unit after the reformation, a detailed comparative analysis of the operating characteristics and peak shaving capabilities of the unit before and after the reformation was carried out. The results show that after the HPLP bypass heat supply reformation, the lower limit of the unit′s electrical load peak regulation can be reduced from 230.9 MW to 161.4 MW with a reduction of 30.1%, by ensuring the heat load of the unit during the heating period is satisfied and the flow rate of reheated steam in hot section do not exceed the limit; when the two middle pressure regulating valves of the case unit are closed to 42%, the lower limit of the unit′s electrical load peak regulation can be further reduced to 140.8 MW; the proportion of bypass heating steam increases from 56.3% to 61.9% with an increase of 5.6%. The peak shaving capacity of the unit has been further improved.

TK262

华北电力科学研究院青年创新项目（KJZ2022004）