多终端灵活的直流电网断路器可以承受多个闪电分析
Yutao Tang1, Hongchun Shu1,2, Kai He2
1The State Key Laboratory of Collaborative Innovation Center for Smart Grid Fault Detection, Protection and Control Jointly, Kunming University of Science and Technology, Kunming, 650500, China.
Scientific reports
|January 24, 2025
概括
多重闪电袭击对混合直流断路器 (DCCB) 构成重大威胁. 虽然消耗能源的分支表现出耐受性,但在这些事件中MOV故障可能会导致严重的过电压,需要仔细设计DCCB.
科学领域:
- 电气工程 电气工程
- 电力系统 电力系统
- 高电压工程 高电压工程
背景情况:
- 雷击对电网构成重大威胁,多个雷击是特别危险的.
- 混合直流断路器 (DCCB) 对于电网保护至关重要,但它们的绝缘容易受到闪电冲击的影响.
- 现有的研究广泛研究多重闪电袭击,突出其对电力基础设施的严重影响.
研究的目的:
- 分析多次雷击对±500千伏张北高压直流电流项目DCCB的影响.
- 在多次闪电条件下,研究DCCB内部的金属氧化物变频器 (MOV) 的能量吸收.
- 在多个闪电袭击期间评估不同DCCB分支机构的过电压水平.
主要方法:
- 使用实时数字模拟器开发了一个DCCB的模拟模型.
- 该模型是基于±500千伏张北高压直流电流项目中DCCB的参数.
- 在模拟多个闪电冲击场景下,分析了闪电侵入波和MOV能量吸收.
主要成果:
- 消耗能源的DCCB分支表现出对多次闪电袭击的某种程度的耐受性.
- 在多个闪电袭击下,消耗能源的分支内部的MOV故障可能会导致关键的过电压问题.
- 在多个闪电袭击条件下,在各种DCCB分支机构的过电压水平被量化.
结论:
- DCCB的设计和选择必须考虑到多次闪电袭击带来的重大风险.
- 确保DCCB中的MOV的稳定性对于在严重的闪电事件中减轻过压风险至关重要.
- 为了提高电网可靠性,需要进一步研究DCCB对多次闪电打击的弹性.
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