高压电机定子线棒端部沿面电位梯度分布的非接触式测量方法
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摘要
基于高压电机用碳化硅防晕层材料场致(或电致)发光特性设计了一种线棒端部沿面电位梯度(或切向电场)分布的非接触式测量装置。首先在高压交流电压下应用光电倍增管测量了校正线棒的电致发光特性,得到了典型碳化硅防晕层的电致发光强度与施加电压梯度的拟合关系曲线。然后应用该测量方法获得了试验线棒端部电致发光分布特性,进一步分析得到试验线棒端部沿面的电位梯度分布规律。同时,研究了试验中线棒表面温升与电致发光强度的关系。结果表明:电压梯度最大值分布在线棒端部中低阻叠加部分之后的中阻区域,而高阻区域的电位梯度很小,电致发光强度弱而测量相对困难。试验测量中线棒表面温升高的部位,电致发光强度也大。
A non-contact device for measuring the surface potential gradient of the ends of stator bar was designed based on the electroluminescence characteristics of silicon carbide(SiC) anti-corona coating material for high-voltage motors. Firstly, the electroluminescence characteristics of the correcting stator bar were measured by photomultiplier tube under AC high voltage, and the fitting curve between the electroluminescence intensity and the applied voltage gradient of the typical SiC anti-corona coating was obtained.Secondly, the electroluminescence distribution characteristics of the ends of test bar were obtained by the measurement method, and the distribution law of the surface potential gradient of the ends of test stator bar was obtained. At the same time, the relationship between the temperature rise of the bar surface and the electroluminescence intensity was studied. The results show that the maximum voltage gradient is in the middle-resistance region of the ends of stator bar, while the potential gradient in the high-resistance region is small and the electroluminescence intensity is so weak that it is difficult to measure. The position with high temperature rise on the stator bar surface also has high electroluminescence intensity.
A non-contact device for measuring the surface potential gradient of the ends of stator bar was designed based on the electroluminescence characteristics of silicon carbide(SiC) anti-corona coating material for high-voltage motors. Firstly, the electroluminescence characteristics of the correcting stator bar were measured by photomultiplier tube under AC high voltage, and the fitting curve between the electroluminescence intensity and the applied voltage gradient of the typical SiC anti-corona coating was obtained.Secondly, the electroluminescence distribution characteristics of the ends of test bar were obtained by the measurement method, and the distribution law of the surface potential gradient of the ends of test stator bar was obtained. At the same time, the relationship between the temperature rise of the bar surface and the electroluminescence intensity was studied. The results show that the maximum voltage gradient is in the middle-resistance region of the ends of stator bar, while the potential gradient in the high-resistance region is small and the electroluminescence intensity is so weak that it is difficult to measure. The position with high temperature rise on the stator bar surface also has high electroluminescence intensity.
引文
[1]吴晓蕾. 27kV级发电机定子线圈绝缘研制[J].上海电力,2005,25(4):363-368.
[2]李振海,赵慧春,李景玉.三峡水轮发电机定子线棒防晕材料及防晕结构的研究[J].绝缘材料,2002,35(6):8-12.
[3]梁智明,漆临生,皮如贵.三峡发电机定子线棒防晕结构和工艺的优化[J].东方电气评论,2005,19(9):142-148.
[4]宁叔帆,于昕哲,徐阳,等.利用SiC电致发光特性在线测量防晕层表面电场分布[J].西安交通大学学报,2006,40(10):1120-1124.
[5] OMRANIPOUR R, HAQ S U. Evaluation of grading system of large motors AC stator windings[C]//Conference Record of the 2008 IEEE International Symposium on Electrical Insulation. Chicago,USA:IEEE,2008:158-161.
[6]吕文娥,江秀臣,韩振东.大型发电机定子绕组端部电位分布[J].高压电器,2003,39(2):34-35.
[7]郭磊,宁叔帆,于开坤,等.碳化硅非线性导电特性的研究进展[J].绝缘材料,2005,38(3):60-64.
[8] El-Kishky H. Experience with development and evaluation of corona-suppression systems for HV rotating machines[J].IEEE Transactions on Dielectrics and Electrical Insulation,2002,9(4):569-576.
[2]李振海,赵慧春,李景玉.三峡水轮发电机定子线棒防晕材料及防晕结构的研究[J].绝缘材料,2002,35(6):8-12.
[3]梁智明,漆临生,皮如贵.三峡发电机定子线棒防晕结构和工艺的优化[J].东方电气评论,2005,19(9):142-148.
[4]宁叔帆,于昕哲,徐阳,等.利用SiC电致发光特性在线测量防晕层表面电场分布[J].西安交通大学学报,2006,40(10):1120-1124.
[5] OMRANIPOUR R, HAQ S U. Evaluation of grading system of large motors AC stator windings[C]//Conference Record of the 2008 IEEE International Symposium on Electrical Insulation. Chicago,USA:IEEE,2008:158-161.
[6]吕文娥,江秀臣,韩振东.大型发电机定子绕组端部电位分布[J].高压电器,2003,39(2):34-35.
[7]郭磊,宁叔帆,于开坤,等.碳化硅非线性导电特性的研究进展[J].绝缘材料,2005,38(3):60-64.
[8] El-Kishky H. Experience with development and evaluation of corona-suppression systems for HV rotating machines[J].IEEE Transactions on Dielectrics and Electrical Insulation,2002,9(4):569-576.