提升风电消纳水平的电力系统灵活性措施经济性评估方法研究

Economic Evaluation of Power System Flexibility Means for Improvement of Wind Power Integration

近年来,中国风电并网容量不断增大,出现了严重的弃风现象,随着各类技术可行的灵活性措施提出,亟需研究经济合理的措施组合以降低弃风量。为此,提出一种提升风电消纳能力的电力系统灵活性措施的经济性评估方法。首先,构建基于成本效益的经济性评价指标,即减少风电弃风量的单位成本,以量化各类灵活性措施对提高电网风电消纳能力的效果;然后,采用时序生产模拟模型量化分析系统的年度弃风总量,生产模拟模型考虑常规电源、风电及负荷,以小时为仿真粒度进行机组组合和经济调度;最后,构建了灵活性措施的年化成本模型。提出的指标及其评估方法具有较好的普适性,能够量化评估各类系统灵活性措施针对缓解弃风的经济性,并获得成本最低的组合方案,对能源主管部门制定针对性的政策措施具有指导意义和应用价值。

In recent years, because of lack of overall power system flexibility for both generation and transmission, wind energy curtailment remains huge amount along with the increase of wind power penetration. A method of economic evaluation for power system flexibility means to promote the accommodation of wind power is proposed in this paper. Firstly, economic indices are defined to quantitatively evaluate the cost-benefit effect of the improvement of wind power integration for power system flexibility means. The index that reflects the unit cost for reducing wind power curtailment and the means with lowest unit cost will be the optimal solution. Secondly, a chronological production cost simulation model is established, which considers the conventional generator, the wind generation, and the electric load. Simulation performs security constrained day ahead unit commitment and real time economic dispatch. Finally, cost models for power systems flexibility means are built. In the case study, systems with the flexibility means are simulated for a period of one year using proposed chronological production cost model to calculate the total amount of wind curtailment for the corresponding means. The unit costs of wind integration improvement for different flexibility means are obtained. In the end, the lowest cost flexibility means is achieved through the quantitative comparison of cost benefit analysis. The proposed method in this paper can quantitatively evaluate the economy of various flexibility means for promoting the accommodation capability of wind generation. Therefore, it is valuable for system planners and decision-makers to effectively and economically determine the means to improve wind generation integration capability.