变压器短路阻抗在线监测的场路耦合法仿真及试验

Simulation and Experiment on Field-circuit Coupling Method for Online Monitoring for Transformer Short-circuit Impedance

目前变压器短路阻抗在线监测的研究主要基于电路等效的理论推导,所采用电路模型仿真无法模拟变压器发生绕组变形时磁场的变化。为了给变压器短路阻抗在线监测装置的开发提供更加精细的仿真与实际运行数据支持,设计了绕组可轴向活动的单相双绕组油浸式变压器。根据变压器的实际参数对其进行"磁场-电路"耦合法仿真,研究计算变压器正常运行与绕组发生轴向位移情况下短路阻抗的大小,并开展相应的试验对仿真结果进行验证。得到的试验结果与仿真结果一致,表明该仿真方法能够正确仿真变压器在线运行情况;并且结果显示,当绕组发生轴向位移时短路阻抗增加。

Current major research on online monitoring for transformer short-circuit impedance is based on theoretical derivation of equivalent circuit and the circuit model used can＇t simulate change of magnetic field caused by winding deformation of the transformer. In order to provide more detailed simulating and actual operating data supports for development of the online monitoring device, this paper discusses design of a single-phase double-winding oil-immersed transformer with axial active winding. According to actual parameters of the transformer, it makes magnetic field and circuit coupling simulation and studies short-circuit impedance under conditions of normal operation of the transformer and axial displacement of winding. Meanwhile, it develops corresponding experiments to verify simulating results. The experimental results are in agreement with simulating results, which indicates that this method can correctly simulate online operation condition of the transformer and short-circuit impedance increases as axial displacement of winding occurs.