Aggregation of demand-side flexibility plays a crucial role in helping improve the system-wide performance of power grids. However, little considered is the potential negative impact of self-interested flexibility aggregators, who are being strategic for their own benefit at the cost of other market participants or even system-wide performance. This article aims to theoretically analyze this negative impact, as well as propose a corresponding mitigation method. Specifically, we consider a strategic aggregator that derives the optimal bidding strategy of the flexibility bounds (for cumulative energy and instantaneous power consumption) and trades electricity in a pool. A multi-period bi-level program with a DC network setup is considered. The upper-level problem represents the aggregator’s cost minimization, and the lower-level problem represents the market clearing process. Based on this bi-level formulation, our theoretical analysis shows that the potential negative impact of the strategic behavior on the system generation cost, the payment of the fixed loads, and the payment of the non-strategic aggregators depends on the bus locations of both the strategic and non-strategic aggregators. We propose to additionally charge the strategic aggregator for the newly introduced congestion so as to avoid system performance degradation. The analytical results are validated via simulations.

中文翻译：

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电力市场需求侧灵活性的聚集：负面影响分析和缓解方法

需求方灵活性的聚集在帮助改善电网的全系统性能方面起着至关重要的作用。但是，很少有人考虑利己的灵活性聚合器的潜在负面影响，这些聚合器正在为自己的利益而进行战略制定，而付出的代价是其他市场参与者甚至整个系统的绩效。本文旨在从理论上分析这种负面影响，并提出相应的缓解方法。具体来说，我们考虑一个战略聚合器，该聚合器可得出灵活性范围的最佳出价策略（针对累积能量和瞬时功耗），并在池中进行交易。考虑具有DC网络设置的多周期双层程序。较高层的问题代表了聚合器的成本最小化，下层问题代表了市场清算过程。基于这种双层公式，我们的理论分析表明，战略行为对系统生成成本，固定负载的支付以及非策略聚合器的支付的潜在负面影响取决于两者的总线位置战略和非战略聚合者。我们建议为新引入的拥塞额外收取战略聚合器费用，以避免系统性能下降。分析结果通过仿真验证。非战略性聚合器的付款取决于战略性和非战略性聚合器的总线位置。我们建议为新引入的拥塞额外收取战略聚合器费用，以避免系统性能下降。分析结果通过仿真验证。非战略性聚合器的付款取决于战略性和非战略性聚合器的总线位置。我们建议为新引入的拥塞额外收取战略聚合器费用，以避免系统性能下降。分析结果通过仿真验证。