Summary
International Symposium on Electromagnetic Compatibility
2009
Session Number:21R2
Session:
Number:21R2-3
Method of Estimating Calibration Accuracy for Capacitive Voltage Probe
T. Masuda, N. Kuwabara, R. Kobayashi,
pp.117-120
Publication Date:2009/7/20
Online ISSN:2188-5079
Summary:
Capacitive voltage probe (CVP) can measure the common mode disturbance voltages without contact to cables. A common-mode voltage needs to be measured using the calibration unit when a calibration of CVP is carried out. Therefore, the accuracy of calibration should be evaluated, because it is important for an EMC conformity test to confirm validity of a result obtained by CVP. This paper proposes the evaluation method for correction factor of calibration unit using S-parameters. The calibration accuracy was evaluated by the coefficient, αasm that was obtained from S-parameters of the calibration unit. The coefficient was calculated using FDTD method and was measured from 0.1 MHz to 100 MHz to evaluate the proposed method. The results indicated that the deviation between the calculated and measured value is within 0.6 dB from 0.1 to 30MHz. This means that the coefficient, αasm, is effective to evaluate the accuracy. The coefficient, αasm, was also measured using the calibration unit and CVP when a wire radius and a kind of cable were changed. The results indicated that the αasm was within 1 dB from 0.1 MHz to 30 MHz.