基于仿真与实验的变压器负荷侧直流偏磁特性研究

Simulation and experiment study on DC bias characteristics of transformer load side model

直流偏磁问题对输变电设备及电力系统的正常运行造成干扰。针对直流偏磁的负荷侧情形,基于UMEC变压器模型的PSCAD平台仿真与相同电气模型下的实验研究反映出交直流磁通叠加使励磁电流发生畸变,磁滞特性作用明显。在偏磁电流计算上,提出考虑漏磁、直流磁通的Φ-I回线对应法,最后以实验验证了该方法的准确性。

The normal operation of the power transmission equipments and power system are disturbed by the DC bias problem often. The simulation based on UMEC model of PSCAD and the experiment using the same electrical type are used to study DC bias characteristics of transformer load side model, and reflects the distortion of excitation bias current and hysteresis obviously. To calculate bias current, the method of Ф-I corresponding in hysteresis loop is pro- posed with magnetic leakage and DC flux taken into account. Finally, the experimental results prove the validity of the proposed method.