燃煤发电机组检修间隔优化研究

Research on optimization of maintenance intervals for coal-fired generating units

煤炭价格波动、发电负荷降低及电力市场改革给燃煤发电企业的经济效益带来了越来越大的影响。为降低燃煤火电机组的检修费用,建立了考虑机组上网电量、检修投入、非计划停运及机组能耗变化等因素的检修优化模型,并以某2×300 MW机组电厂为例进行了计算。结果表明,随检修投入增加,机组检修优化后的收益变大:在机组检修费用为1000万元/次、检修时间为500 h时,每优化减少1次检修所获得的收益可以超过1500万元。但另一方面,机组检修优化的收益还受非计划停运事件次数、非计划停运设备维修费用及机组能耗变化的影响,因此机组检修间隔的延长也需要有一定的范围。研究表明,所建模型可以用于机组检修间隔优化的定量分析,能够为电厂合理安排检修次数提供技术参考。

To reduce the overhaul cost of coal-fired thermal power units,this paper establishes an overhaul optimization model,which takes into account factors such as on-grid power consumption,overhaul investment,unplanned outage,and energy consumption change of units.The overhaul investment is directly reduced due to the reduction of overhaul times.The increase of online time of the unit enhances the online power and thus increases the online income.However,with the enlargement of unit maintenance interval,the probability of unplanned outage events increases.Besides,the coal consumption level of the unit also increases due to the increase in the air leakage rate of the air preheater and the increase of ash in the heated area.Taking a 2×300 MW unit power plant as an example,the calculation results show that with the increase of maintenance investment,the benefits of unit maintenance optimization improved.When the maintenance cost of the unit is 10 million yuan each time and the maintenance time is 500 h,the benefits obtained from every reduction of maintenance can exceed 15 million yuan.Nevertheless,the benefit of unit maintenance optimization is also affected by the number of unplanned outage events,the maintenance cost of unplanned outage equipment,and the change of unit energy consumption.Therefore,the extension of the unit maintenance interval also needs a certain range.The calculation results of this model show that the model established in this paper can be used for quantitative analysis of unit maintenance interval optimization,and it can provide technical reference for power plants to arrange maintenance times reasonably.