油纸绝缘套管内部压强监测中温度的影响及消除措施研究

Study on Influence of Temperature on Internal Pressure Monitoring of Oil paper Insulated Bushing and Its Elimination Measures

摘要:

油纸绝缘套管内部发生放电或过热性故障时，内部的绝缘油和绝缘纸会分解产生特征气体，随气体的增加内部压强相应增加，从而通过监测套管内部压强可实现缺陷的监测与预警。但是环境温度和负荷电流的变化会导致套管内部温度的变化，从而引起内部压强的变化，为采用压强监测进行预警带来了干扰。为消除温度对压强预警带来的干扰，文中研究了温度对内部压强的影响规律，提出了共模抑制的方法来消除温度的影响。结果表明，该方法可以有效消除套管压强监测时的温度影响。

Abstract:

When discharge or overheating fault occurs in oil paper insulated bushing, the internal insulation oil and insulation paper will be decomposed to produce characteristic gas, and the internal pressure will increase correspondingly with the increase of gas, so that the monitoring and warning of defects can be realized by monitoring the internal pressure of bushing. However, the changes in ambient temperature and load current will lead to the changes of temperature inside the bushing, which will lead to the changes in internal pressure, thus bringing disturbance to the early warning using pressure monitoring. In order to eliminate the disturbance of temperature on pressure warning, the law of the influence of temperature on internal pressure is studied, and the method of common mode suppression to eliminate the influence of temperature is proposed. The results show that the proposed method can effectively eliminate the influence of temperature on pressure monitoring of bushing.