Pollution flashover behavior of hydrophobic polymeric insulating interfaces at insulators under DC voltage stress and combined DC and AC voltage stress

直流电压应力和交直流联合电压应力下绝缘子疏水性聚合物绝缘界面的污闪行为

• 批准号: 518862170
• 负责人: Professor Dr. Stefan Kornhuber
• 金额: --
• 依托单位: Fakultät Elektrotechnik- und Informatik
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/518862170?language=en
• 关键词: Pollution; flashover; behavior; hydrophobic; polymeric

The demand of electrical energy is increasing to achieve the goals to limit the global warming process and to replace natural gas and oil due to the actual war, because the electrical energy is a key resource in all sectors. To transfer the electrical energy from the generation plants to the users an increasing capability of transmission lines are necessary. Additionally, the time period (gradient) of the significant increase in the electrical energy demand is short, on the other side the erection of new transmission power lines will take certain (usually a longer) time period from the planning till the commissioning due to different reasons. Back to the early 1970s, the transmission of electrical energy by using a mixed AC and DC voltage with the motivation of increasing the maximum transferable electrical power have been discussed. Based on the maximum transferable load can be upgraded by approx. 85 % at existing transmission lines by using a mixed of AC and DC transfer. The insulators need to provide the necessary insulation for the mixed AC and DC voltage in combination with the polluted surrounding. For the immediate usage of the mixed AC and DC voltage no change at the transmission line insulators and towers needs to be done. The design of porcelain, glass and composite insulates is understood and standardized by long-term practical experience for AC and DC. For the behavior and design of mixed insulators for combined AC and DC limited experience and investigations are available. Especially, the behavior of dry band discharges but also the pollution flashover characteristic may be different related to the missing zero crossing of the current (the pre-arcs will not distinguish). This different behavior will have effects to the behavior of polluted insulators with hydrophilic behavior (glass and porcelain insulators) as well also the hydrophobic behavior (composite insulators). The main goal of this research project is to investigate the differences between pure AC, DC and mixed AC and DC stress in the pollution flash over characteristic and the tracking erosion behavior, extract the processes and based on the result to adapt the available models. With these investigations, the fundamental data for the design and usage of transmission lines with a mixed AC and DC voltage are provided.

由于实际战争的影响，为了实现限制全球变暖进程和取代天然气和石油的目标，电能的需求正在增加，因为电能是所有部门的关键资源。为了将电能从发电厂输送到用户手中，需要增加输电线路的容量。此外，电能需求大幅增长的时间段(梯度)较短，另一方面，由于各种原因，新输电线路的架设从规划到投产需要一定(通常较长)的时间段。早在20世纪70年代初，人们就讨论了利用交直流混合电压传输电能，以增加最大可转移电能的动机。基于最大可转移载荷，可升级约为。85%的现有输电线路采用交流和直流混合传输。绝缘子需要为交直流混合电压提供必要的绝缘，并结合污染的环境。为了立即使用交流和直流混合电压，不需要在输电线路绝缘子和铁塔上做任何改变。通过长期的交、直流实践经验，对瓷器、玻璃和复合绝缘子的设计有了深入的了解和规范。对于交、直流混合绝缘子的性能和设计，只有有限的经验和调查可用。特别是，干带放电的行为以及污染闪络特性可能与电流的遗漏过零点有关(预弧将无法区分)。这种不同的行为将对受污染的亲水绝缘子(玻璃和瓷绝缘子)以及疏水行为(复合绝缘子)的行为产生影响。本研究的主要目的是研究纯交流、直流和交直流混合应力在污染闪络特性和跟踪腐蚀行为上的差异，提取过程，并根据结果对现有模型进行修正。通过这些研究，为交直流混合电压输电线路的设计和使用提供了基础数据。