一种换流变压器绝缘老化监测方法，该方法通过调整换流变压器阀侧绕组三相中性点接线、测量老化前阀侧某一相绕组的差分绝缘漏电流、提取所述老化前的差分绝缘漏电流中的共模分量和差模分量并计算老化前的共模等效电容和差模等效电容：然后同样方法计算老化后的共模等效电容和差模等效电容；最后根据老化前、后的差模等效电容的差值和老化前、后的共模等效电容的差值，计算所述差模等效电容的差值和共模等效电容的差值的比值，所述比值表征阀侧绕组对地主绝缘老化的位置。本发明采用非入侵式、经济性高、实施便捷的测试方式，避免额外测试装置的接入，测试结果不受电网负荷波动影响的方法，对绝缘老化情况的监测具有鲁棒性。

A method for monitoring insulation aging of a converter transformer. The method comprises adjusting the three-phase neutral point connection of the valve side winding of the converter transformer, measuring the differential insulation leakage current of a certain phase winding on the valve side before aging, and extracting the differential insulation before aging. Calculate the common-mode and differential-mode components in the leakage current and calculate the common-mode equivalent capacitance and differential-mode equivalent capacitance before aging: then calculate the common-mode equivalent capacitance and differential-mode equivalent capacitance after aging in the same way; The difference between the differential mode equivalent capacitance before and after the aging and the difference between the common mode equivalent capacitance before and after aging are calculated, and the ratio of the difference between the differential mode equivalent capacitance and the difference between the common mode equivalent capacitance is calculated, The ratio represents the position of the insulation aging of the valve side winding to the ground. The invention adopts a non-invasive, highly economical and convenient testing method, avoids the connection of additional testing devices, and the testing results are not affected by the load fluctuation of the power grid, and the monitoring of the insulation aging condition is robust.