Research on Electronic Voltage Transducer Based on Spiral Air-core Coil

Presently,most of electronic voltage transformer applies theory of voltage dividing to supply secondary voltage signals and there is not enough electric isolation between the primary and secondary circuit.For this reason,a new type of electronic voltage transformer based on spiral air-core coil current sensor is proposed.In series with the capacitor,the current sensor can detect the current in it to reflect the primary high voltage.As current sensor,the spiral air-core coil has good linearity,big bandwidth without magnetic saturation problem.To meet different requirements of measurement accuracy ratings,two signal processing circuits are provided to supply with related voltage signals.Power amplifiers are adopted in the signal processing circuit to guarantee against losing capability of sustaining secondary load.The experiment data indicate that the electronic voltage transformer has fast dynamic response,a big bandwidth and high linearity.