电力变压器频域介电谱特性仿真模型的对比研究  

Comparison Study on Simulation Models of Frequency Domain Dielectric Spectroscopy of Power Transformer

作　　者：王丽[1] 董明[1] 王健一[2] 李金忠[2] 林鹏 WANG Li;DONG Ming;WANG Jianyi;LI Jinzhong;LIN Peng(State Key Laboratory of Electrical Insulation and Power Equipment,Xi＇an Jiaotong University,Xi＇an 710049,China;China Electric Power Research Institute,Beijing 100192,China;China XD Group Co.,Ltd.,Xi＇an 710075,China)

机构地区：[1]西安交通大学电力设备电气绝缘国家重点实验室,陕西西安710049 [2]中国电力科学研究院,北京100192 [3]中国西电集团有限公司,陕西西安710075

出　　处：《绝缘材料》2018年第9期76-81,共6页Insulating Materials

基　　金：国家自然科学基金资助项目(50907051);国家电网公司科技项目(GY71-15-052)

摘　　要：基于50 k V单相双绕组实际变压器的结构和尺寸,构建了用于变压器频域介电谱(FDS)仿真的改进型有限元模型和集总参数电路模型,并将两者的仿真结果与传统有限元模型仿真结果进行对比,分析了变压器绕组及高压绕组与变压器壁间结构对变压器FDS结果的影响。结果表明:传统的变压器仿真模型仅考虑了高低压绕组间的油纸绝缘结构,以此法评估变压器的绝缘状态会产生较大误差。变压器高压绕组与变压器壁间结构使变压器复介电常数实部在全频段内稍有降低;虚部在低频段内稍微增大,在中高频段内呈现降低趋势。这可由绝缘油与油浸纸板的FDS特性差异来解释。由于绕组自身存在电阻和电感,且相邻两饼绕组间存在电导和电容,考虑绕组影响后变压器的复介电常数实部和虚部均呈现降低趋势。最后通过试验初步验证了所得结论的正确性。Based on the structure and size of 50 k V single phase two-winding transformer, the modified finite element model（FEM） and lumped element circuit（LEC） model for simulating the frequency domain dielectric spectroscopy of transformer were constructed, and their simulation results were compared with that of traditional finite element model. The effects of transformer winding and the structure between high voltage winding and transformer wall on the FDS results of transformer were analyzed.The results show that the traditional transformer simulation model considers the oil-paper insulation structure between high and low voltage windings only, if we use this method to evaluate the insulation condition of transformer, there would be large errors. The structure between high voltage winding and transformer wall makes the real part of complex permittivity of transformer decrease slightly in the whole frequency range, and the imaginary part increases slightly in low frequency range and decreases in middle and high frequency ranges, this can be explained by the difference of FDS characteristics between insulating oil and oil-immersed paper. Due to the existence of resistance and inductance in windings and the existence of conductivity and capacitance between adjacent windings, both the real part and the imaginary part of complex permittivity of transformer decrease when the influence of windings is considered. Finally,the correctness of the obtained conclusion was verified by experiments.

关 键 词：电力变压器 频域介电谱 传统有限元模型 改进型有限元模型 集总参数电路模型 

分 类 号：TM855[电气工程—高电压与绝缘技术]