基于离散积分法的电磁式互感器比差检定方法OA

The traditional method for calibrating the ratio difference of transformers relies on comparison with high-precision standard transformers.Once the accuracy of the standard transformer was abnormal,the calibration results wouldl be significantly affected.In order to overcome this limitation,a new method for calibrating the ratio difference of electromagnetic current transformers was proposed,which did not rely on high-precision standards.Firstly,the factors affecting the ratio difference of electromagnetic current transformers were analyzed,and the relationship between the ratio difference,working current,and external load was derived.Then,based on the ratio difference characteristics of the transformer under different loads,a ratio difference verification test was designed based on two different loads.A method for estimating the discrete derivative of the ratio difference curve based on the load increment coefficient was proposed,and finally,the ratio difference curve was obtained through discrete integration.Simulation experiments showed that compared to traditional methods,this method estimates a ratio difference that is closer to the true value,with a maximum relative error of no more than 5%,and the results are not affected by the accuracy of standard transformers.