污秽绝缘子串的放电特性及运行状态评估的研究
摘要
绝缘子的污秽闪络是对供电可靠性危害极大的区域性事故,被列为电力系统头号安全大敌,防止污闪事故的发生对保证电网安全运行极为重要。虽然污秽引起的绝缘闪络事故在电网总事故中占第二位,仪次于雷害事故,但污闪事故造成的损失却是雷害事故的10倍。
国内外虽对绝缘子交、直流污闪特性研究较多,但缺乏对实际输电线路染污绝缘子的耐压特性、闪络特性以及泄漏电流等参数的综合分析,缺乏对运行中的绝缘状态综合评估的研究。本文在总结国内外研究成果的基础上,在输配电装备及系统安全与新技术国家重点实验室(重庆大学)的人工气候室内对220kV输电线路普通型玻璃绝缘子串(FC-100/146)、瓷绝缘子串(XP-70)和复合绝缘子(FXBW—220/110—2150)进行了大量的耐受特性和闪络特性的试验研究,并对耐受和闪络过程中的泄漏电流进行分析。针对不同盐密(ESDD)、灰密(NSDD)和污秽分布不均匀度等对绝缘子串耐受特性和闪络特性的影响,通过试验研究及理论分析得到:绝缘子串的耐受电压和闪络电压随着盐密和灰密的增加下降;耐受和闪络电压随着污秽分布不均匀度的增加而上升,上下表面污秽分布均匀时最低,此时的高湿绝缘子串在运行电压下极易发生闪络;泄漏电流有效均值、最大有效值均随着盐密值的增大而增加,并与盐密值呈幂函数关系。灰密值对泄漏电流的影响规律与盐密一致,但二者对泄漏电流有效值的影响因素在本质上是不同的;根据污闪络电压以及泄漏电流与盐、灰密和不均匀度的关系,得到了满足耐受通过和泄漏电流有效均值不超过40mA这两个条件绝缘子运行发生污闪的威胁程度安全区域图。根据安全区域图和实测污秽度,能够指导确定对运行中绝缘子实施清扫的周期,向状态清扫过渡,提高输电线路运行可靠性。
The pollution flashover is the regional accident which has great harm to the power supply reliability and is regarded as the top archenemy to the power system. It is of paramount importance to prevent pollution flashover accidents and ensure the safe operation of the power grid. Insulation flashover, as a result of the pollution, is the second leading cause in contribution to power grid accident, only next to the lightning, but the loss brought by it is as ten times as that by the lightning.
There have been many researches on the characteristics of DC/AC pollution flashover of insulator at home and abroad, however the comprehensive analysis of the factors such as withstand voltage, flashover performance and leakage current, as well as the comprehensive evaluation of insulation status of the lines, are still scarce. Under the comprehensive summarization of former domestic and foreign researches, the withstand performance and flashover characteristics of glass insulators (FC-100/146), porcelain insulators (XP-70) and composite insulators (FXBW—220/110—2150) of 220kV lines are tested in the phytotron in The State Key Laboratory of Power Transmission Equipment & System Security and New Technology and the leakage current are analyzed. Based on different impacts of ESDD, NSDD and the uneven distribution of pollution on the withstand and flashover characteristics of insulators, it can be concluded from the testing result and theoretical analysis that: the withstand and flashover voltage of insulators decrease along with the increase of ESDD, NSDD; The withstand and flashover voltage of insulators rise along with the increase of unevenness of the distribution of the pollution and reach a minimum when the distribution is even, while it has a great possibility for the flashover taking place on the wet insulators; The relationship between the max virtual value and ESDD shows a exponential function; The same goes with the impact of NSDD but these two rules are essentially different. According to these relationship, the security region in which the mean virtual value of withstand and leakage currents are both less than 40mA. According to the security region and the practical status of pollution, the cleaning period of insulator and the transition to condition based cleaning can be decided to improve the reliability of transmission lines.
国内外虽对绝缘子交、直流污闪特性研究较多,但缺乏对实际输电线路染污绝缘子的耐压特性、闪络特性以及泄漏电流等参数的综合分析,缺乏对运行中的绝缘状态综合评估的研究。本文在总结国内外研究成果的基础上,在输配电装备及系统安全与新技术国家重点实验室(重庆大学)的人工气候室内对220kV输电线路普通型玻璃绝缘子串(FC-100/146)、瓷绝缘子串(XP-70)和复合绝缘子(FXBW—220/110—2150)进行了大量的耐受特性和闪络特性的试验研究,并对耐受和闪络过程中的泄漏电流进行分析。针对不同盐密(ESDD)、灰密(NSDD)和污秽分布不均匀度等对绝缘子串耐受特性和闪络特性的影响,通过试验研究及理论分析得到:绝缘子串的耐受电压和闪络电压随着盐密和灰密的增加下降;耐受和闪络电压随着污秽分布不均匀度的增加而上升,上下表面污秽分布均匀时最低,此时的高湿绝缘子串在运行电压下极易发生闪络;泄漏电流有效均值、最大有效值均随着盐密值的增大而增加,并与盐密值呈幂函数关系。灰密值对泄漏电流的影响规律与盐密一致,但二者对泄漏电流有效值的影响因素在本质上是不同的;根据污闪络电压以及泄漏电流与盐、灰密和不均匀度的关系,得到了满足耐受通过和泄漏电流有效均值不超过40mA这两个条件绝缘子运行发生污闪的威胁程度安全区域图。根据安全区域图和实测污秽度,能够指导确定对运行中绝缘子实施清扫的周期,向状态清扫过渡,提高输电线路运行可靠性。
The pollution flashover is the regional accident which has great harm to the power supply reliability and is regarded as the top archenemy to the power system. It is of paramount importance to prevent pollution flashover accidents and ensure the safe operation of the power grid. Insulation flashover, as a result of the pollution, is the second leading cause in contribution to power grid accident, only next to the lightning, but the loss brought by it is as ten times as that by the lightning.
There have been many researches on the characteristics of DC/AC pollution flashover of insulator at home and abroad, however the comprehensive analysis of the factors such as withstand voltage, flashover performance and leakage current, as well as the comprehensive evaluation of insulation status of the lines, are still scarce. Under the comprehensive summarization of former domestic and foreign researches, the withstand performance and flashover characteristics of glass insulators (FC-100/146), porcelain insulators (XP-70) and composite insulators (FXBW—220/110—2150) of 220kV lines are tested in the phytotron in The State Key Laboratory of Power Transmission Equipment & System Security and New Technology and the leakage current are analyzed. Based on different impacts of ESDD, NSDD and the uneven distribution of pollution on the withstand and flashover characteristics of insulators, it can be concluded from the testing result and theoretical analysis that: the withstand and flashover voltage of insulators decrease along with the increase of ESDD, NSDD; The withstand and flashover voltage of insulators rise along with the increase of unevenness of the distribution of the pollution and reach a minimum when the distribution is even, while it has a great possibility for the flashover taking place on the wet insulators; The relationship between the max virtual value and ESDD shows a exponential function; The same goes with the impact of NSDD but these two rules are essentially different. According to these relationship, the security region in which the mean virtual value of withstand and leakage currents are both less than 40mA. According to the security region and the practical status of pollution, the cleaning period of insulator and the transition to condition based cleaning can be decided to improve the reliability of transmission lines.
引文
[1]孙才新,司马文霞,舒立春,大气环境与电气外绝缘,北京,中国电力出版社,2002.
[2]蒋兴良,舒立春,张永记,张志劲,胡建林,人工污秽下盐/灰密对普通悬式绝缘子串交流闪络特性的影响,中国电机工程学报.
[3]蒋兴良,舒立春,张志劲,张永记,盐/灰密对不同型式绝缘子交流人工闪络特性的影响,中国电机工程学报.
[4]蔡炜,肖勇,吴光亚,±500kV直流线路绝缘子串自然积污规律,高电压技术,2003,7.
[5]顾乐观,孙才新,电力系统的污秽绝缘,重庆,重庆大学,1988.
[6]张仁豫,绝缘污秽放电,北京,清华大学,1993.
[7]宿志一,直流输电外绝缘配置方法,2007年全国架空输电线路技术交流研讨会交流文集
[8]宿志一,范建斌,周军,新污区划分标准的绘制说明及应用,2007年全国架空输电线路技术交流研讨会交流文集
[9]王靖勤,沈庆河,刘琨,500kV线路自然积污规律的试验研究,中国电力,1995,6.
[10]马振良,不带电绝缘子和带电绝缘子积污程度的对比实验,高电压技术,1993,12.
[11]王彪,陈焕金,陈伟,复合绝缘子的积污规律初探,河北电力技术,2003,5.
[12]岳乔,张开贤,郝旭东,绝缘子自然染污规律的研究,华北电力技术,1996,12.
[13]张开贤,悬式绝缘子串自然积污规律的探讨,电网技术,1997,3.
[14]张永耀,悬式绝缘子自然积污性能的研究,电网技术,1989,4.
[15]关志成,张福增,王新,王黎明,特高压直流输电线路外绝缘设计和绝缘子选型,高电压技术,2006,12.
[16]林方新,高鑫,刘伟兴,800kV直流输电线路外绝缘设计探讨,广东输电与变电技术,2005,5.
[17]宿志一,超高压变电设备污秽外绝缘设计的重点,中国电力,2001,1.
[18]房柯夫,吴光亚,危鹏,1000kV交流输电线路污秽外绝缘设计方法的研究,电瓷避雷器,2007,3.
[19]吴光亚,蔡炜,卢燕龙,肖勇,王刚,黄伟中,交流输电线路绝缘子串片数的选择,高电压技术,2002,2.GB/T 16434-1996高压架空线路和发电厂、变电所环境污区分级及外绝缘选择标准.
[20]徐通训,贯彻输变电设备外绝缘等级新国家标准(GB/T16434-1996),东北电力技术,2000,9.
[21]Naito K et al,Improvement of the DC voltage insulation efficiency of suspension insulators under contaminated conditions,IEEE transaction on electrical insulation,1988,Vol.22,No.6:1025-1032.
[23]W.Lampe et al,Long-term tests of HVDC insulators under natural pollution conditions at the Big Eddy Test Center,IEEE trans on power delivery,1989,Vol.4,No.1:248-259
[24]Caixin Sun,Yuchun Tian,Xingliang Jiang,Lichun Shu,Wenxia Sima,Flashover performance and voltage correction of iced and polluted HV insulator string at high altitude of 4000m and above,Properties and Applications of Dielectric Materials,2003,Proceedings of the 7International Conference on,June,2003,Vo 1.1,No.5:141 - 145.
[25]Fong.F,Operational experience on HVDC and HVAC insulators at Sylmar Converter Station,Electrical Insulation,2002,Conference Record of the 2002 IEEE International Symposium on,7-10,April 22.
[26]Gorur,R.S and H.M.Schneider,Surface Resistance Measurements on Nonceramic Insulators,A Task Force Report of the IEEE Working Group on Insulator Contamination,IEEE Power Engineering Society,Paper PE-572(05 2001).
[27]田玉春,蒋兴良,舒立春等,高海拔地区10kV合成绝缘子覆冰交流闪络特性及电压校正,高电压技术,2002,28(6):13-15.
[28]孙才新,舒立春,蒋兴良等,高海拔、污秽、覆冰环境下超高压线路绝缘子交、直流放电特性及闪络电压校正研究,中国电机工程报,2002,22(11):115-120.
[29]舒立春,蒋兴良,田春等,海拔4000m以上地区4种合成绝缘子覆冰交流闪络特性及电压校正,中国电机工程学报,2004,24(1):97-101(in Chinese).
[30]蒋兴良,谢述教,舒立春等,低气压下三种直流绝缘子覆冰闪络特性及其比较,中国电机工程学报,2004,24(9):158-162
[31]李晓峰,污秽电介质表面电特性及新型绝缘子的研究,华中科技大学,2003.
[32]司马文霞,武利会,蒋兴良等,低气压下覆冰染污10kV直流合成绝缘子电气特性,中国电机工程学报,2004,24(7):122-126.
[33]江秀臣,安玲,韩振东等,等值盐密现场测量方法的研究,中国电机工程学报,2000,Vol.20,No.4:40-49.
[34]李永毅,王丹丹,架空输电线路绝缘子运行性能分析与建议,西北电力技术,N0.4,2004.
[35]张玲,刘如星,输电线路绝缘子污闪机理,电力学报,1999,14(2):87-90.
[36]GB/T 4585-2004交流系统用高压绝缘了的人工污秽试验,2004.
[37]张仁豫,绝缘污秽放电,北京:水利电力出版社,第一版,1994.
[38]孙才新,司马文霞,大气环境与电气外绝缘,第一版,北京:中国电力出版社,2002.
[2]蒋兴良,舒立春,张永记,张志劲,胡建林,人工污秽下盐/灰密对普通悬式绝缘子串交流闪络特性的影响,中国电机工程学报.
[3]蒋兴良,舒立春,张志劲,张永记,盐/灰密对不同型式绝缘子交流人工闪络特性的影响,中国电机工程学报.
[4]蔡炜,肖勇,吴光亚,±500kV直流线路绝缘子串自然积污规律,高电压技术,2003,7.
[5]顾乐观,孙才新,电力系统的污秽绝缘,重庆,重庆大学,1988.
[6]张仁豫,绝缘污秽放电,北京,清华大学,1993.
[7]宿志一,直流输电外绝缘配置方法,2007年全国架空输电线路技术交流研讨会交流文集
[8]宿志一,范建斌,周军,新污区划分标准的绘制说明及应用,2007年全国架空输电线路技术交流研讨会交流文集
[9]王靖勤,沈庆河,刘琨,500kV线路自然积污规律的试验研究,中国电力,1995,6.
[10]马振良,不带电绝缘子和带电绝缘子积污程度的对比实验,高电压技术,1993,12.
[11]王彪,陈焕金,陈伟,复合绝缘子的积污规律初探,河北电力技术,2003,5.
[12]岳乔,张开贤,郝旭东,绝缘子自然染污规律的研究,华北电力技术,1996,12.
[13]张开贤,悬式绝缘子串自然积污规律的探讨,电网技术,1997,3.
[14]张永耀,悬式绝缘子自然积污性能的研究,电网技术,1989,4.
[15]关志成,张福增,王新,王黎明,特高压直流输电线路外绝缘设计和绝缘子选型,高电压技术,2006,12.
[16]林方新,高鑫,刘伟兴,800kV直流输电线路外绝缘设计探讨,广东输电与变电技术,2005,5.
[17]宿志一,超高压变电设备污秽外绝缘设计的重点,中国电力,2001,1.
[18]房柯夫,吴光亚,危鹏,1000kV交流输电线路污秽外绝缘设计方法的研究,电瓷避雷器,2007,3.
[19]吴光亚,蔡炜,卢燕龙,肖勇,王刚,黄伟中,交流输电线路绝缘子串片数的选择,高电压技术,2002,2.GB/T 16434-1996高压架空线路和发电厂、变电所环境污区分级及外绝缘选择标准.
[20]徐通训,贯彻输变电设备外绝缘等级新国家标准(GB/T16434-1996),东北电力技术,2000,9.
[21]Naito K et al,Improvement of the DC voltage insulation efficiency of suspension insulators under contaminated conditions,IEEE transaction on electrical insulation,1988,Vol.22,No.6:1025-1032.
[23]W.Lampe et al,Long-term tests of HVDC insulators under natural pollution conditions at the Big Eddy Test Center,IEEE trans on power delivery,1989,Vol.4,No.1:248-259
[24]Caixin Sun,Yuchun Tian,Xingliang Jiang,Lichun Shu,Wenxia Sima,Flashover performance and voltage correction of iced and polluted HV insulator string at high altitude of 4000m and above,Properties and Applications of Dielectric Materials,2003,Proceedings of the 7International Conference on,June,2003,Vo 1.1,No.5:141 - 145.
[25]Fong.F,Operational experience on HVDC and HVAC insulators at Sylmar Converter Station,Electrical Insulation,2002,Conference Record of the 2002 IEEE International Symposium on,7-10,April 22.
[26]Gorur,R.S and H.M.Schneider,Surface Resistance Measurements on Nonceramic Insulators,A Task Force Report of the IEEE Working Group on Insulator Contamination,IEEE Power Engineering Society,Paper PE-572(05 2001).
[27]田玉春,蒋兴良,舒立春等,高海拔地区10kV合成绝缘子覆冰交流闪络特性及电压校正,高电压技术,2002,28(6):13-15.
[28]孙才新,舒立春,蒋兴良等,高海拔、污秽、覆冰环境下超高压线路绝缘子交、直流放电特性及闪络电压校正研究,中国电机工程报,2002,22(11):115-120.
[29]舒立春,蒋兴良,田春等,海拔4000m以上地区4种合成绝缘子覆冰交流闪络特性及电压校正,中国电机工程学报,2004,24(1):97-101(in Chinese).
[30]蒋兴良,谢述教,舒立春等,低气压下三种直流绝缘子覆冰闪络特性及其比较,中国电机工程学报,2004,24(9):158-162
[31]李晓峰,污秽电介质表面电特性及新型绝缘子的研究,华中科技大学,2003.
[32]司马文霞,武利会,蒋兴良等,低气压下覆冰染污10kV直流合成绝缘子电气特性,中国电机工程学报,2004,24(7):122-126.
[33]江秀臣,安玲,韩振东等,等值盐密现场测量方法的研究,中国电机工程学报,2000,Vol.20,No.4:40-49.
[34]李永毅,王丹丹,架空输电线路绝缘子运行性能分析与建议,西北电力技术,N0.4,2004.
[35]张玲,刘如星,输电线路绝缘子污闪机理,电力学报,1999,14(2):87-90.
[36]GB/T 4585-2004交流系统用高压绝缘了的人工污秽试验,2004.
[37]张仁豫,绝缘污秽放电,北京:水利电力出版社,第一版,1994.
[38]孙才新,司马文霞,大气环境与电气外绝缘,第一版,北京:中国电力出版社,2002.