基于谐波分析的牵引变压器绕组短路电抗监测方法

为在线监测牵引变压器绕组变形,利用牵引供电系统中奇次谐波丰富的特点,按照用某时刻变压器的谐波电压和谐波电流表达绕组短路电抗的设计思想,提出基于谐波分析的牵引变压器绕组短路电抗在线监测新方法。建立基于谐波电压和谐波电流计算变压器绕组短路电抗的数学模型,以单相变压器为例进行绕组短路电抗仿真计算,并根据成都铁路局西昌变电所1号主变压器实测谐波数据计算绕组短路电抗。结果表明:仿真结果与设定值的误差小于0.3%;与Maxwell电桥测量法、常用短路电抗在线监测方法相比,基于谐波分析的牵引变压器绕组短路电抗在线监测方法的测量误差小于2.5%,从而验证了新方法理论上可行,监测精度高。

Monitoring Method for Winding Short-Circuit Reactance of Traction Transformer Based on Harmonic Analysis

In order to on-line monitor winding deformations of traction transformer,a new method based on the idea of expressing short-circuit reactance with harmonic voltages and currents is proposed,according to the character of rich harmonics in traction power system.The mathematical model for calculating the short-circuit reactance of traction transformer is proposed,in which expression harmonic voltages and currents involved.The new method is validated by simulating on a single-phase transformer,then it is used for No.1 main transformer in Xichang Substation of Chengdu Railway Administration.Simulation results errors are below 0.3%,and the practice test errors are less than 2.5% comparing to the data from Maxwell Bridge measuring.All the results show that the new method is theoretically feasible and highly precise.