基于机会约束的主动配电网动态经济调度方法

Chance-Constrained Dynamic Economic Dispatch Method for Active Distribution Networks

分布式电源在主动配电网中大规模接入后,需要对主动配电网进行动态经济调度,以降低主动配电网整体运行成本。由于可再生能源出力具有随机性和不确定性,主动配电网的动态经济调度面临广泛随机性,这对调度策略的可靠性提出挑战。为此,提出一种基于机会约束的主动配电网动态经济调度模型,该模型考虑了分布式电源出力及负荷预测的不确定性。由于该模型无法被直接求解,文章利用凸松弛原理,将原机会约束模型转化为确定性混合二阶锥规划模型。基于IEEE-33节点系统的算例表明,该模型可有效求解出主动配电网的最优经济调度策略,且电压越限率和线路容量越限率被严格控制在给定的机会约束概率以内。此外,算例结果表明所提出基于机会约束的经济调度方法优于传统确定性经济调度和鲁棒经济调度模型。

The integration of large-scale distributed generation requires dynamic economic dispatch to reduce the total operational cost of active distribution networks. With the wide penetration of renewable energy in distribution network, great challenges have been addressed on the accuracy of economic dispatch with the concern of uncertainty. This paper proposes a stochastic dynamic economic dispatch model of active distribution network, in which the uncertainties of distributed generation output and load forecasting are incorporated. This model becomes a chance-constrained optimization problem and cannot be directly solved. In this paper, authors describe a relaxation algorithm to relax it as a deterministic mixed second order cone programming model. Numerical tests on IEEE 33-node distribution network shows that the model can be effectively solved with predefined constraint-violating-rate, and this method outperforms the traditional robust optimization model.