With the introduction of high voltage direct current (HVDC)-system, especially the voltage source converter (VSC)-based implementation, new degrees of freedom have been made accessible for system operation and for ensuring system security where they can be utilized either in the form of preventive or curative actions. This work presents an optimization model meant to determine a set of preventive and curative relief measures. Thereby, both methods are not calculated in a successive approach, but the optimization of the curative actions is nested into the preventive optimization. By doing so, a feedback can be given in cases the preventive optimization is evolving in regions where no feasible curative actions can be provided. A numerical case study is conducted, where the calculation of the curative set-points is performed with a linearized power flow model. Thereby, an effect is shown, where preventive insecure contingencies appear as curative feasible as the linearized model does not show any violated constraints.

中文翻译：

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网状双极 HVDC-Overlay-Systems 的预防和治疗措施

随着高压直流 (HVDC) 系统的引入，尤其是基于电压源换流器 (VSC) 的实施，系统操作和确保系统安全性获得了新的自由度，它们可以用于预防或治疗措施的形式。这项工作提出了一个优化模型，旨在确定一组预防性和治疗性缓解措施。因此，两种方法都不是以连续方法计算的，而是将治疗措施的优化嵌套在预防优化中。通过这样做，如果在无法提供可行的治疗措施的区域中进行预防性优化，则可以给出反馈。进行了数值案例研究，其中治疗设定点的计算是用线性化潮流模型进行的。因此，显示了一种效果，其中预防性不安全的意外事件似乎具有治疗可行性，因为线性化模型没有显示任何违反约束。