二次设备内部卡件与测量回路接地异常检测

Detection of the Grounding Abnormity of the Internal Card Part and Measuring Circuit of Secondary Equipment

二次设备内部卡件与测量回路的接地一旦出现异常,很可能导致一次故障时严重的信号干扰,保护设备不能正确动作,因此对于这些设备接地状况的检测就显得尤为重要。提出了针对二次设备内部卡件与测量回路接地异常的检测方法,可在变电站等电磁环境复杂的区域稳定准确地检测毫伏级的模拟信号,在低电压情况下实现精密弱电设备的检测,力求用安全的方法有效地发现此类缺陷。

Once there is abnormal grounding between the internal card parts of the secondary equipment and the measuring circuit, it is likely to lead to serious signal interference during the primary fault, and incorrect action of the protection equipment. Therefore, it is particularly necessary to detect the grounding condition of these equipment. This paper presents a detection method for the ground abnormity of the internal card parts and measuring loop of the secondary equipment, which can detect the analog signal of millivolt level stably and accurately in the area of complex electromagnetic environment such as substation, and realize the detection of the precise weak current equipment under the condition of low voltage, so as to effectively find such defects in a safe way.