一种考虑权重不确定性的机组综合评价模型

Comprehensive Performance Evaluation Model for Power Units Considering Weight Uncertainty

针对大型燃煤机组深层次节能降耗阶段的综合性能评价问题,以机组与周围环境组成的广义能量系统为对象,考虑机组可靠性、经济性及环保性等因素,综合运用蒙特卡罗方法、熵权法及层次分析法(AHP)得到评价指标线性组合权重,并采用灰色关联方法建立了燃煤机组性能综合评价模型。对6台600 MW燃煤机组应用模型进行了实例分析,以AHP权重为基础进行正态分布随机抽样,进而得到组合权重,分别取各机组指标最优值组成机组理想方案,对各机组方案与理想方案的灰色关联度进行了统计分析。结果不仅可以给出常规综合评价方法下的机组性能优劣排序,而且能够给出各机组对指标权重同时变化时的敏感性信息。当抽样标准差σ由0.015增大到0.045时,4号、3号和1号机组灰色关联度变化范围增大明显,且1号机组与6号及2号机组关联度取值区间有交集。结果表明,该评价模型具有较好的不确定因素处理能力,评价结果同时综合了专家知识与客观信息,符合客观实际,具有较好的适用性。

For comprehensive performance evaluation of large coal-fired units in the deep energy saving phase, a com- prehensive evaluation model based on Monte Carlo method was established, which took the unit and its surrounding en- vironment as object, considering the unit energy consumption, water consumption and pollution emissions factors, using gray relational method and combined weighs method. The linear combined weight was obtained by the Entropy Method and Analytic Hierarchy Process （AHP） method. A case study of six 600 MW coal-fired units was performed. A normal random sampling was carried out based on the AHP weights, and then a group of new index weight was got combined with the entropy weights. Gray relational degree of each unit was analyzed with the ideal solution, which set as the opti- mal value of each evaluation indices. The results can be given not only the merits of unit performance sorting which can be got under regular comprehensive evaluation method, but also the sensitive information of the index weight at the same time. And when the sample standard deviation increases from 0. 015 to 0. 045, the gray relational degree range of unit 4, 3 and 1 is increased significantly, and the value of unit 1 intersect with the unit 2 and 6. The results show that this evaluation model has good ability of uncertainty processing, and also integrating in the expert knowledge and the objective information, thus it is applicable for the coal-fired unit comprehensive evaluation.