Abstract:Problems about stability, efficiency and accuracy in the computation of transformer, which are based on the transient magnetic-electric coupled method, have been concerned. Dynamic inductance is calculated according to the energy perturbation. Combining with the high-order convergence of the fourth Runge-Kutta, the absolutely stable region is determined to judge the convergence of computation. And the variation function of dynamic inductances is established to evaluate the magnetic changing. Then an actual single-phase transformer is modeled and simulated. Computation and case study about normal operation and DC-biasing are given to work out the transient magnetic and equivalent circuit parameters. The varying regularity of coupling parameters in different saturated excitations is learned, and the relation between state matrix and time step is studied. Result shows that the dynamic inductances are feasible to reflect the time-varying magnetic saturation. Compared with the traditional and improved Euler method, the fourth Runge-Kutta takes advantages in stability and accuracy. Meanwhile, the absolutely stable region is valid. On the basis of stability analysis, proper solving frequency of magnetic field can optimize the computational accuracy and efficiency. Tests are carried out to prove the transient magnetic-circuit method and stability analysis, which will be a new way for practical DC-biased transformers.
潘超, 王泽忠, 杨敬瑀, 刘连光. 变压器直流偏磁瞬态场路耦合计算的稳定性分析[J]. 电工技术学报, 2012, 27(12): 226-232.
Pan Chao, Wang Zezhong, Yang Jingyu, Liu Lianguang. Stability Analysis Based on Transient Magnetic-Circuit Coupled Method for DC-Biased Transformer. Transactions of China Electrotechnical Society, 2012, 27(12): 226-232.
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