摘要
针对当前油浸式电力变压器绕组瞬态温升仿真中,采用固定时间步长效率低的问题,提出一种混合变步长方法。首先,采用初始解优化算法,有效减少计算过程中方程的迭代次数;其次,结合本征正交分解算法(properorthogonal decomposition,POD),改善大规模有限元方程组存在的阶数过高、条件数过大的问题,提高了方程的求解效率和数值稳定性;第三,提出自适应(adaptivetimestepping,ATS)-启发式(heuristic time stepping,HTS)混合变步长算法,通过对时间步长的自适应与启发式调整,有效解决瞬态计算中计算效率与计算精度的对立问题;最后,建立油浸式电力变压器绕组二维单分区分匝的流热耦合仿真模型,以验证所提算法的正确性与高效性。数值计算结果表明:在流场中,与固定步长的计算结果相比,混合变步长算法的误差小于0.46%,计算效率提升了18.45倍;在温度场中,与固定步长的计算结果相比,所提算法的误差小于0.04%,计算效率提升了6倍。同时,通过与传统变步长算法的计算结果对比,说明所提混合变步长算法在计算精度、计算效率及变步长效果方面均具有一定优势。此外,还探讨混合变步长计算中,不同的参数设置对瞬态计算结果及状态变化过程的影响,为其工程应用奠定了一定基础。
This paper proposes a hybrid variable step method to address the low efficiency of using fixed time steps in the current transient temperature rise simulation of oil immersed power transformer windings.First,an initial solution optimization algorithm is adopted to effectively reduce the number of iterations of the equation during the calculation process.Secondly,combined with the proper orthogonal decomposition(POD)method,the problems of high order and condition number of large-scale finite element equations are improved,and the solving efficiency and numerical stability of equations are also improved.Thirdly,an adaptive time stepping(ATS)-heuristic time stepping(HTS)hybrid variable step size mehod is proposed,which effectively solves the contradiction between computational efficiency and accuracy in transient calculations through adaptive and heuristic adjustments to the time step size.Finally,this article establishes a two-dimensional single zone and turn separation of oil immersed power transformer windings to verify the correctness and efficiency of the proposed mehod.The numerical calculation results show that in the flow field,compared with the fixed step size calculation results,the error of the hybrid variable step size method is less than 0.46%,and the computational efficiency is improved by 18.45 times.In the temperature field,compared with the calculation results with a fixed step size,the error of the method proposed in this paper is less than 0.04%,and the computational efficiency is improved by 6 times.Meanwhile,by comparing the calculation results with traditional variable step size method,it is demonstrated that the proposed hybrid variable step size method has certain advantages in terms of calculation accuracy,efficiency,and variable step size effect.This article also explores the impact of different parameter settings on the transient calculation results and state change process in hybrid variable step calculation,laying a certain foundation for its engineering application.
作者
刘刚
郝世缘
胡万君
李琳
LIU Gang;HAO Shiyuan;HU Wanjun;LI Lin(Hebei Provincial Key Laboratory of Power Transmission Equipment Security Defense(North China Electric Power University),Baoding 071003,Hebei Province,China;State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources(North China Electric Power University),Changping District,Beijing 102206,China)
出处
《中国电机工程学报》
EI
CSCD
北大核心
2023年第24期9772-9784,共13页
Proceedings of the CSEE
基金
国家重点研发计划项目(2021YFB2401703)。
关键词
初始解优化
本征正交分解
混合变步长
二维瞬态
流热耦合问题
initial solution optimization
proper orthogonal decomposition(POD)
mixed variable time step
two dimensional transient
flow thermal coupling problem
