复合绝缘管的油相容性及热老化性能研究

Study on Oil Compatibility and Thermal Aging Performance of Composite Insulation Tube

采用复合绝缘外套的油浸式设备中,需要使用玻璃纤维增强环氧树脂绝缘管作为主绝缘容器,复合绝缘管与绝缘油长期接触,并且经受各种运行工况的考验。为研究绝缘管与油的相容性和长期运行稳定性,对三种不同配方绝缘管材料进行油浸热老化处理,针对不同老化时间后的绝缘油进行相容性相关的频域介电谱、气相色谱分析;针对不同老化时间的绝缘管材料进行击穿电压试验、局部放电特性试验、表面微观形貌、频域介电频谱等抗热油老化性能研究。根据试验结果,分析了不同老化时间绝缘管材料的抗热油老化能力,对比了不同配方绝缘管材料的抗热油老化能力及抗老化性能。结果表明,较高的浅陷阱密度有利于电荷消散,减少局放的发生,提高耐电特性。此外,老化过程中较低的环氧树脂分解和玻璃纤维断裂程度最终表现为良好的油相容性。该结果可为提高采用复合绝缘外套油浸式设备的运行寿命和可靠性提供优选配方及理论依据。

In the oil-immersed equipment with composite insulation jacket,glass fiber reinforced epoxy resin insulation tube should be used as the main insulation container.The composite insulation tube has long-term contact with the insulating oil,and has been tested under various operating conditions.In order to study the compatibility and long-term stability of insulating pipe and oil,three kinds of insulating pipe materials with different formulations are treated by oil immersion heat aging,and the frequency domain dielectric spectroscopy and gas chromatography related to the compatibility of insulating oil after different aging time are analyzed.The breakdown voltage test,partial discharge characteristic test,surface morphology,frequency domain dielectric spectrum and other anti-thermal oil aging properties of insulating tube materials with different aging time are studied.According to the test results,the thermal oil aging resistance of insulating pipe materials with different aging time is analyzed,and the thermal oil aging resistance and aging resistance of insulating pipe materials with different formulations are compared.The results show that higher shallow trap density is beneficial to charge dissipation,reduce the occurrence of partial discharge and improve the electrical resistance.In addition,the lower degree of epoxy resin decomposition and glass fiber fracture during aging eventually showed good oil compatibility.The results can provide optimal formula and theoretical basis for improving the operation life and reliability of oil immersion equipment with composite insulation jacket.