基于支路电压扰动的接地网腐蚀缺陷诊断研究

Study on Corrosion Defects Diagnosis of Grounding Grid Based on Branch Voltage Disturbance

对接地网进行准确的腐蚀诊断是电力工程中十分关注的问题。为了解决接地网腐蚀诊断过程中计算方程组欠定所导致的诊断精度不高,效果不理想的问题,文中提出一种基于支路电压扰动的接地网腐蚀诊断方法,该方法通过接地网腐蚀前后支路电压的扰动实现腐蚀缺陷支路的定位和腐蚀程度的判断。文中首先理论分析接地网支路电压对支路电阻的灵敏度;其次,利用支路电压扰动特性,建立接地网腐蚀诊断模型,得出支路电压扰动峰值位置、大小与接地网腐蚀支路位置和腐蚀程度的映射规律;最后,实验验证了该方法能够对接地网的支路腐蚀进行有效的诊断。

The accurate corrosion diagnosis of grounding grid is a very concerned problem in the electric power engineering.In order to solve the problem of low diagnosis accuracy and undesired effect due to the undetermined equation of calculation in the process of corrosion diagnosis of grounding grid,a kind of corrosion diagnosis method of grounding grid based on branch voltage disturbance is proposed in this paper,which can achieve the location of the corrosion defect branch and the judgment of corrosion degree through the branch voltage disturbance before and after corrosion of the grounding grid.Firstly,the sensitivity of branch voltage to the branch resistance of grounding grid is theoretically analyzed in this paper.Secondly,the corrosion diagnostic model of the grounding grid is set up by the use of the branch voltage disturbance characteristics so to obtain the mapping rule between the position and magnitude of the peak of branch voltage disturbance voltage and the corrosion branch position corrosion degree of the grounding grid.Finally,it is verified by experiment that the method can perform effective diagnosis of the branch corrosion of the grounding grid.