Investigation On The Large DC Current Measurement Technology

The paper mainly studied several principles and methods of direct current (DC) measurement, particularized several kinds of DC current sensors according to diverter, Hall-effect, The giant magnetoresistance effect, Core type current transformer, DC comparator, Ke Fu Pinsky (Rogowski) coi principle, also DC current sensor mixed combined high-voltage DC transformer, and expounds their appearance, characteristics and their operating characteristics. Secondly, the article engaged in research of Single core magnetic modulator separately, analyzed the magnetic hysteresis loop of ferromagnetic substance, and the wave-shape of Modulator core’s magnetizing current under effect of sine wave current and effect of excitation voltage source comparatively, then verified every part of the methodology by experiments. Base on the resolution, the article raised a new departure——Single-core magnetic modulator measurement on peak differential, and to proposed open loop and closed loop two mode. It manifest them in ways schematic circuit diagram that made up of Hardware and microcontroller.