Abstract
This article describes a design of Current Transformer Comprehensive Character Tester for power test by using advanced chip technology(32-bit ARM microprocessor, 16-bit 6-channel AD converter sampling at the same time)and software skills( synchronous sampling, digital calibration).The instrument can perform volt-ampere characteristic experiment , transformation ratio and polarity experiment , secondary impedance test and 10% error curve drawing for protective current transformer. The traditional testing method for current transformer, especially when drawing the volt-ampere characteristic curve, is not only complex and laborious but also makes greater errors by manual boosting and reading. Thus, it is very necessary to develop a fully automatic Current Transformer Comprehensive Character Tester. To achieve automatic detection, the power frequency booster used for excitation in the test device detaches from manual operation, driven by servo motor, and what’s more, it has function of variable rate driving to adapt to various conditions. The test device can measure the testing voltage and excitation current accurately even if in the case of serious waveform distortion.It also can display, print and save test data as well as curves. This automatic tester greatly enhances the accuracy and efficiency of the characteristic testing for protective current transformer, reducing the labor intensity of the test personnel.
