Abstract Loss Of Offsite Power (LOOP) accident is one of the most important Design Basis Accidents (DBAs) that originate due to loss of the house-load demands which make serious concerns for each NPP. Moreover, in the case of loss of all diesel generators (due to earthquake, etc.), the accident forwards to the Station Black-Out(SBO). Following and learning the Fukushima accident, the cares have been focused on using internal and/or external water resources for the passive management of the SBO accident. In the current study, passive strategies in the VVER-1000/V446 NPP are proposed using a tank in the secondary loop (called Deaerator) for the SBO management. After RELAP5 modeling benchmarking in the steady-state as well as standard SBO management (which are mentioned in the NPP FSAR), two operational SBO management are proposed herein including “Feeds and Bleeds” (in the primary and secondary loops) and also including a Deaerator tank in the secondary side. The results show that using the Deaerator-water tank of the secondary side as well as feed and bleed, the time available for operators before the core heat-up (i.e. fuel cladding temperature of 1200 °C); extends to 35000 s. Obviously; it gives a good opportunity for plant operators to access further time for using other facilities/methods to avoid core damage.

中文翻译：

---

VVER1000/V446核电厂全站停电事故被动管理创新及应急运行程序开发

摘要 场外电力损失 (LOOP) 事故是最重要的设计基准事故 (DBA) 之一，其起源于房屋负荷需求的损失，这引起了每个核电厂的严重关注。此外，在所有柴油发电机丢失的情况下（由于地震等），事故将转移到车站停电（SBO）。在福岛事故发生后，学习了福岛事故后，关注的重点是利用内部和/或外部水资源对 SBO 事故进行被动管理。在当前的研究中，VVER-1000/V446 核电厂中的被动战略被提议使用二级回路中的油箱（称为除氧器）进行 SBO 管理。在稳态中的 RELAP5 建模基准测试以及标准 SBO 管理（在 NPP FSAR 中提到）之后，这里提出了两种操作 SBO 管理，包括“进料和放气”（在初级和次级回路中），还包括次级侧的除气罐。结果表明，使用二次侧除氧器-水箱以及进料和放气，操作人员在堆芯加热前可用的时间（即燃料包壳温度为1200℃）；延长至 35000 秒。明显地; 它为工厂操作员提供了一个很好的机会，可以有更多的时间使用其他设施/方法来避免堆芯损坏。延长至 35000 秒。明显地; 它为工厂操作员提供了一个很好的机会，可以有更多的时间使用其他设施/方法来避免堆芯损坏。延长至 35000 秒。明显地; 它为工厂操作员提供了一个很好的机会，可以有更多的时间使用其他设施/方法来避免堆芯损坏。