瞬态电磁-温度场耦合计算中自适应时间步长研究  

Research on the Adaptive Time Step in Transient Calculation of Coupled Electromagnetic and Thermal Fields

作　　者：张宇娇[1] 汪振亮 徐彬昭 黄雄峰[1] 智李[1] Zhang Yujiao;Wang Zhenliang;Xu Binzhao;Huang Xiongfeng;Zhi Li(Hubei Key Laboratory of Cascaded Hydropower Stations Operation&Control China Three Gorges University Yichang 443002 China)

机构地区：[1]三峡大学梯级水电站运行与控制湖北省重点实验室,宜昌443002

出　　处：《电工技术学报》2018年第19期4468-4475,共8页Transactions of China Electrotechnical Society

基　　金：国家自然科学基金资助项目(51577106)

摘　　要：瞬态温度场响应时间比电磁场长,在采用有限元法求解瞬态电磁-温度场顺序耦合时,若采用统一计算时间步长会导致温度场求解次数过多而增加计算时间。该文提出自适应时间步长耦合方法,采用指数平滑法预测电磁-温度场耦合时间间隔,并在两个相邻的耦合时间节点间,根据响应特征值和预测-校正法计算电磁场、温度场最佳离散步长。与传统等步长耦合方法对比,电磁、温度场均使用最佳的离散步长,同时避免了温度场的过频计算,减少了计算时间。最后,以通电铜导环为例,采用自适应时间步长耦合计算铜导体在交流电流作用下的瞬态温升,与传统等步长耦合方法相比,计算相对误差在1%以内,总计算时间减少26.6%,证明了该方法的有效性。When using finite element method(FEM)to solve transient electromagnetic-thermal indirect coupling,the response time of temperature field is longer than the electromagnetic field.And if a unified computing time step was used in solving,extras solving number occur in thermal field calculations which increase the total computation time.To solve the electromagnetic-thermal coupling problem,an adaptive coupling time step method is proposed in this paper.First,the coupling time is predicted by exponential smoothing forecast.And then between the two coupling time nodes,the best discrete time steps of thermal and electromagnetic field are calculated by predictor-corrector method and the response eigenvalue method.Compared with the traditional unified time step coupling method,electromagnetic and thermal field are using the best discrete time steps.The extra calculation number of temperature field is avoided.Finally,the proposed method is employed to calculate a conducting copper ring’s temperature within 1%under an AC excitation as an example.The results show that the calculation time is 26.6%less.Thus,the effectiveness of the proposed method is verified.

关 键 词：有限元法 电磁-温度场耦合 自适应时间步长 指数平滑预测 响应特征值 

分 类 号：TM155[电气工程—电工理论与新技术]