The massive growth in the integration of variable renewable energy sources is producing several challenges in the operation of power systems and its associated markets. In this context, flexibility has become a critical attribute to allow the system to react to changes in generation or demand levels. Thus, it is critical for market signals at both short and long term scales to include flexibility features, to align agents' incentives with systemic flexibility requirements. In this paper, different pricing schemes for short-term markets are studied, based on various relaxations of the unit commitment problem, including convex-hull approximations, with the aim of representing operational flexibility requirements in a more explicit way. Extensive simulations illustrate the performance of the proposed schemes, as compared to conventional ones, in terms of the capability of the system to properly incentivize flexibility attributes, resulting in better agents' cost recovery and more variable renewable energy utilization. The results show that short-term pricing schemes considered improve the long-term signals for flexible investments but additional changes to market design are still required. Thus, there is a need to revisit historical practices for pricing rules by incorporating additional flexibility-related attributes into them. Several alternatives are discussed and policy recommendations based on these considerations are provided.

可变可再生能源整合的大规模增长给电力系统及其相关市场的运营带来了若干挑战。在这种情况下，灵活性已成为允许系统对发电量或需求水平变化做出反应的关键属性。因此，对于短期和长期规模的市场信号来说，至关重要的是要包括灵活性功能，以使代理商的激励措施与系统灵活性要求保持一致。本文基于单位承诺问题（包括凸包壳近似）的各种松弛，研究了针对短期市场的不同定价方案，目的是更明确地表示运营灵活性要求。广泛的仿真说明了与传统方案相比，所提出方案的性能，在系统适当激励灵活性属性的能力方面，可以提高代理商的成本回收率，并提高可再生能源的利用率。结果表明，考虑的短期定价方案改善了灵活投资的长期信号，但仍需要对市场设计进行其他更改。因此，需要通过将其他与灵活性相关的属性纳入定价规则来重新审视定价规则的历史惯例。讨论了几种选择，并提供了基于这些考虑的政策建议。结果表明，考虑的短期定价方案改善了灵活投资的长期信号，但仍需要对市场设计进行其他更改。因此，需要通过将其他与灵活性相关的属性纳入定价规则来重新审视定价规则的历史惯例。讨论了几种选择，并提供了基于这些考虑的政策建议。结果表明，考虑的短期定价方案改善了灵活投资的长期信号，但仍需要对市场设计进行其他更改。因此，需要通过将其他与灵活性相关的属性纳入定价规则来重新审视定价规则的历史惯例。讨论了几种选择，并提供了基于这些考虑的政策建议。