含新能源电力系统的风险调度策略比对与影响分析

Comparison and impact analysis of risk dispatch strategies of new power system

中文关键词: 风险调度  备用  两阶段随机规划模型  机会约束模型  置信度

英文关键词: risk dispatch  reserve  two-stage stochastic optimization modelling  chance-constrained approach  confidence

中文摘要:

      针对含新能源电力系统的不同风险调度策略的原理及其影响展开分析,有助于调度人员获得更为详细的运行参考信息,从而推动风险调度策略的实践应用。首先,本文利用Copula理论构建某预测值条件下的误差概率分布,经过蒙特卡洛采样得到众多新能源预测出力场景,作为风险调度策略分析的边界。然后,在计划编制环节兼顾新能源出力的不确定性,构建了基于两阶段随机规划模型、机会约束模型、确定性模型3种调度策略,并根据拉格朗日乘子方法推导出各节点边际成本的构成分量,完成不同风险调度策略的比对分析。最后,基于某省级电网的算例测试结果表明：通过调整机会约束的置信度可以涵盖另外两种方法得到的结果。其中两阶段方法得到的结果最为激进；而确定性方法结果较为保守。此外,新能源出力占比较高时,在负荷低谷时段为保证留出足够的负备用,风险调度结果极易发生弃电现象。

英文摘要:

      Comparison and impact analysis of different risk dispatch strategies of new power system can help dispatchers get more detailed operation information, so as to promote their practical skills when making decisions about risk dispatch strategies. First, Copula theory is used to build the probabilistic distribution of forecast error given a specified forecast value, and multiple scenarios can be obtained by Monte-Carlo sampling. Second, three different risk dispatch strategies are built and compared, which are two-stage stochastic optimization modelling, chance-constrained approach and deterministic models, and then derives and analyses day-ahead electricity prices based on Lagrange multiplier method. Last, the example analysis shows that the results of other two models can be covered by setting different confidence levels in chance-constrained approach. The two-stage stochastic optimization model is rather conservative, while the deterministic model is rather aggressive. It also shows that it is prone to curtail new energy power during low-load periods in a high proportion new energy power system.