Title :
Digital impedance bridge based on a two-phase generator
Author_Institution :
Tech. Univ. Wroclaw, Poland
fDate :
4/1/1997 12:00:00 AM
Abstract :
A digital impedance bridge composed of two digital sine-wave generators and inductive voltage dividers (IVD´s) designed for precision comparison of different impedance standards is described. To increase the reliability of measurement and its accuracy, an unknown is compared to many reference standards and a special method of estimation is applied. The bridge enables one to measure impedance from 10 Ω up to 100 kΩ in the frequency range between 100 Hz and 1 kHz with a relative uncertainty smaller than 50 μΩ/Ω which is mainly due to short term instability of the digital source and uncertainty of reference standards
Keywords :
bridge instruments; digital instrumentation; electric impedance measurement; least squares approximations; measurement errors; measurement standards; voltage dividers; waveform generators; 10 ohm to 100 kohm; 100 Hz to 1 kHz; digital impedance bridge; digital source; impedance standards; inductive voltage dividers; reference standards; relative uncertainty; sine-wave generators; two-phase generator; Bridge circuits; Counting circuits; Detectors; Frequency measurement; Impedance measurement; Least squares methods; Measurement standards; Sampling methods; Switches; Voltage;
Journal_Title :
Instrumentation and Measurement, IEEE Transactions on
