Abstract:Power transformer tank bulging,rupture,even explosion occurs from time to time when suffering internal short-circuit faults.The resulting disasters such as oil spray and fire greatly jeopardize the safety of nearby staffs,apparatus and public environment.In order to reveal the mechanism of abrupt oil pressure increase and successive tank deformation and rupture inside the transformer,this work describes this complex process with two separate stages,i.e. fault pressure and tank stress.The model and corresponding solution of each stage is provided respectively.Firstly,the transformer fault pressure model,tank transient mechanical model and pressure-mechanical field coupling model are introduced.Based on the law of energy conservation,the relationship among the fault energy,oil pressure and stress is interpreted.Secondly,a 3D finite element model is built for a 360 MV·A/220 kV power transformer.In addition,the stress-strain relationship of the tank wall is described by employing a multi-linear isotropic hardening model.Thirdly,the distribution and variation of the internal fault pressure and stress in the transformer tank wall are simulated and analyzed for a variety of fault locations and severities.The simulation results show that some positive correlations exist among the fault energy,oil pressure amplitude and tank stress.It is also found that countermeasures,such as rapid fault clearance and reinforcements for the stress concentration area,are helpful to improve tank’s capability of overpressure endurance and to reduce the risk of oil spray,fire,tank explosion and other secondary disasters.
闫晨光,郝治国,张保会,郑涛. 电力变压器油箱形变破裂建模及仿真[J]. 电工技术学报, 2016, 31(3): 180-187.
Yan Chenguang ,Hao Zhiguo, Zhang Baohui, Zheng Tao. Modeling and Simulation of Power Transformer Tank Deformation and Rupture. Transactions of China Electrotechnical Society, 2016, 31(3): 180-187.
[1] Abi-Samra N,Arteaga J,Darovny B,et al.Power transformer tank rupture and mitigation:a summary of current state of practice and knowledge by the task force of IEEE power transformer subcommittee[J].IEEE Transactions on Power Delivery,2009,24(4):1959-1967. [2] Mahieu W R.Prevention of high fault ruptures of pole-type distribution transformers[J].IEEE Transactions on Power Apparatus Systems,1975,94(5):1698-1707. [3] Foata M,Iordanescu M,Hardy C.Computational methods for the analysis of explosions in oil-insulated electrical equipment[J].IEEE Transactions on Power Systems,1988,3(1):186-293. [4] Hamel A,Dastous J B,Foata M.Estimating overpressures in pole-type distribution transformers,part Ⅰ:tank withstand evaluation[J].IEEE Transactions on Power Delivery,2003,18(1):113-119. [5] Dastous J B,Foata M,Hamel A.Estimating overpressures in pole-type distribution transformers,part Ⅱ:prediction tools[J].IEEE Transactions on Power Delivery,2003,18(1):120-127. [6] Muller S,Brady R.Prevention of transformer tank explosion,part 1:experimental tests on large transformers[C]//2008 ASME Pressure Vessels and Piping Division Conference,Chicago,USA,2008:357-365. [7] Brady R,Muller S.Prevention of transformer tank explosion,Part 2:development and application of a numerical simulation tool[C]//2008 ASME Pressure Vessels and Piping Division Conference,Chicago,USA,2008:49-58. [8] Perigaud G,Muller S,De Bressy G,et al.Contribution to the study of transformer tank rupture due to internal arcing development of a computer simulation tool[C]//IEEE Power and Energy Society General Meeting-Conversion and Delivery of Electrical Energy in the 21st Century,Pittsburgh,USA,2008:1-8. [9] Dastous J B,Lanteigne J,Foata M.Numerical method for the investigation of fault containment and tank rupture of power transformers[J].IEEE Transactions on Power Delivery,2010,25(3):1657-1665. [10]闫晨光,张保会,郝治国,等.电力变压器油箱内部故障压力特征建模及仿真[J].中国电机工程学报,2014,34(1):179-185. Yan Chenguang,Zhang Baohui,Hao Zhiguo,et al.Modeling and simulation of pressure characteristics of power transformer tanks’ internal faults[J].Proceedings of the CSEE,2014,34(1):179-185. [11]Foata M,Dastous J B.Power transformer tank rupture prevention[C]//CIGRé 2010,Paris,France,2010:1-11. [12]王维俭,王祥珩,王赞基.大型发电机变压器内部故障分析与继电保护[M].北京:中国电力出版社,2006. [13]Dastous J B,Foata M.Analysis of faults in distribution transformers with MSC/PISCES-2DELK[C]//MSC World Users’ Conference,Los Angeles,USA,1991:1-13. [14]Patrick Bastard,Pierre Bertrand,Michel Meunier.A transformer model for winding fault studies[J].IEEE Transactions on Power Delivery,1994,9(2):690-699. [15]Mladen Kezunovic,Yong Guo.Modeling and simulation of the power transformer faults and related protective relay behavior[J].IEEE Transactions on Power Delivery,2000,15(1):44-50. [16]王赞基,刘秀成,陈香辉.用于内部故障分析的变压器电感参数计算模型[J].电力系统自动化,2000,24(24):21-25. Wang Zanji,Liu Xiucheng,Chen Xianghui.An inductance calculation model of power transformer for internal fault analysis[J].Automation of Electric Power Systems,2000,24(24):21-25. [17]王雪,王增平.变压器内部故障仿真模型的设计[J].电网技术,2004,28(12):50-52. Wang Xue,Wang Zengping.Study of simulation of transformer with internal faults[J].Power System Technology,2004,28(12):50-52. [18]杨理才,孙杰中,刘蔚,等.变压器匝间短路建模及其实际应用[J].电力系统保护与控制,2014,42(8):140-145. Yang Licai,Sun Jiezhong,Liu Wei,et al.Transformer inter-turn short circuit modeling and its application[J].Power System Protection and Control,2014,42(8):140-145. [19]王雪,王增平.基于有限元法的变压器电感参数计算方法的研究[J].电力系统保护与控制,2009,37(24):11-14. Wang Xue,Wang Zengping.An investigation on transformer inductance calculation based on finite element method[J].Power System Protection and Control,2009,37(24):11-14. [20]Temkin S.Elements of acoustics[M].New York:Acoustical Society of America,2001:189-193. [21]Ringot E.Polycopie de mecanique des milieux continus elasticite lineaire[M].Toulouse:Université Paul Sabatier Toulouse Ⅲ,2010. [22]Courant R,Friedrichs K O,Lewy H.On the partial differential equations of mathematical physics[J].IBM Journal of Research and Development,1967,11(2):215-234. [23]Hackl A,Hamberger P.Predict the rupture of transformer tanks with static FEM analysis[C]//Electrical Machines 2012 20th International Conference,Sapporo,Japan,2012:2358-2361.