110kV电力系统变压器中性点保护用触发控制间隙

摘要

针对110 kV电力系统中变压器中性点过电压保护间隙存在的“拒动”和“误动”问题,提出了一种利用被保护点过电压进行触发控制的球-球电极保护间隙.对新型保护间隙的基本工作原理进行了详细阐述,通过实验研究了新型保护间隙保护功能实现的可行性,并对新型保护间隙主要部分的选择与设计进行了说明.通过新型保护间隙样机的相应试验对其保护作用的实际效果进行了验证.结果表明:新型保护间隙不仅可以与现有的中性点保护避雷器进行理想的配合,实现对变压器中性点的完备保护,新型保护间隙的无源性为其在电力系统的推广应用提供方便.%Being directed against the problem of ' refuse operation' and ' unwanted operation' in the currently used overvoltage protection scheme for neutral point of power transformers in 110 kV power system, the paper put forward a new kind of protective gap which has a pair of ball-shaped electrodes and the breakdown of the gap is triggered and controlled by the overvoltage at the protected point, and can be used to realize an ideal cooperation with arrester.The basic work principle of the new type of protective gap has been elaborated in detail.Some tests are performed to study the feasibility of realizing function of the new type of protective gap.The method of selection and design for the major part of new type of protective gap is explained.The actual protective effect of the new protective gap has been verified finally through some corresponding experiments performed on the prototype of the new protective gap.Research result shows; The new protective gap may not only be used, with existing arrester using for neutral point protective of power transformer, to carry out an ideal protection for the neutral point of power transformers , but also the passive characteristic of the new protective gap offers a convenience for its application in power system.