JPS6447963A - Tester - Google Patents

Abstract

PURPOSE:To enable freely variable setting of magnetization characteristic of a current transformer, by generating a simulation signal of a magnetic flux corresponding to a fault current containing a DC component as flowing into the primary side of the current transformer with a first circuit while the current is made to correspond to the magnetization characteristic with a second circuit. CONSTITUTION:A tester 1 is made up of a setting section 10, a simulation circuit 20 for magnetic flux, a secondary current waveform simulation circuit 30. Here, the circuit 20 comprises an AC component fault current generating section 201, a DC component fault current generating section 202, an addition circuit 203 and an integration circuit 204 and the circuit 203 adds up an AC component fault current and a DC component fault current having attenuation characteristic to generate a fault current waveform, which is integrated with the circuit 204 to obtain a simulation signal of a magnetic flux which is induced in the core of a current transformer when there is no magnetic saturation. The circuit 30 simulates non-linearity of magnetization characteristic with a non-linearity simulation circuit 301 and differentiates it with a differentiation circuit 302 to take out a secondary current waveform. This enables freely variable setting of the magnetization characteristic of the current transformer.