基于EBSILON的热电厂热电负荷分配优化研究

Optimization Study on Thermal and Electric Load Distribution of Thermal Power Plant based on EBSILON

为优化热电厂热电负荷分配,提高热电厂运行热经济性,利用EBSILON软件建立某热电厂350和330 MW热电联产机组热力系统仿真模型和热经济性模型,根据抽汽点的蒸汽焓值进行热负荷计算,采用(火用)分析方法对热电联产机组进行能耗特性分析,得到两台机组在安全运行区间内的(火用)效率分布规律。通过遗传算法,研究不同热电负荷分配方式对热电厂热经济性的影响,进一步对热电厂典型日的热电负荷进行分配优化。结果表明:当机组供热流量达到最大值且电负荷为该供热流量下的最大值时,机组的(火用)效率达到最大值,对电负荷和热负荷进行分配优化的节能收益大于对单一因素优化;采用遗传算法优化热电负荷后,典型工况下全厂标准煤耗量降低1.75 t/h、发电标准煤耗率降低3.65 g/(kW·h)、(火用)效率提高0.49%;典型日全厂标准煤耗量降低35 t/d、发电标准煤耗率降低3.16 g/(kW·h)、(火用)效率提高0.41%。

In order to optimize the heat and electric load distribution of thermal power plant and improve the thermal economy of thermal power plant operation, the thermal system simulation model and thermal economy model of 350 MW and 330 MW cogeneration units of a thermal power plant were established by using EBSILON software. The heat load was calculated according to the steam enthalpy at the extraction point. The energy consumption characteristics of cogeneration units were analyzed by the exergy analysis method, and the distribution law of exergy efficiency of the two units in the safe operation section was obtained. Through genetic algorithm, the influence of different heat and electric load distribution methods on the thermal economy of thermal power plant was studied, and the typical daily heat and electric load distribution of thermal power plant was further optimized. The results show that when the heating flow of the unit reaches the maximum value and the power generation reaches the maximum value under the heating flow, the exergy efficiency of the unit reaches the maximum value, and the energy saving benefit of optimizing the distribution of electric load and heat load is greater than that of optimizing a single factor.After using genetic algorithm to optimize the cogeneration load, under typical working conditions, the standard coal consumption of the whole plant is reduced by 1.75 t/h, the standard coal consumption rate of power generation is reduced by 3.65 g/(kW·h),and the exergy efficiency is increased by 0.49%;in a typical day, the standard coal consumption of the whole plant is reduced by 35 t/d, the standard coal consumption rate of power generation is reduced by 3.16 g/(kW·h),and the exergy efficiency is increased by 0.41%.