Application of Parallel and Equal Ampere Turns Method on Field Error Calibration GTA

This article presents a new measuring method of errors of current transformer at the entrance in the large generator(GTA) : parallel and equal ampere turns method.using theoretical calculations and magnetic field simulation,the article analyzed the characteristics of parallel method which different from the traditional serial method.By field checking errors of the No.1 generating Unit current transformer in Ling Ao nuclear power plant,we verify that the parallel and equal ampere turns method has higher accuracy than the traditional serial method.In addition,by simulation,this article analyzes the influent of the stray flux of the scene on the measuring accuracy of second test circuit.