Evaluation of the synchronous generation and synchronous sampling technique for the determination of low frequency AC quantities

The synchronous synthesis and synchronous measurement of sinusoidal signals using a single internal clock frequency of a high-resolution digitizer as proposed by Ramm et al (IEEE Trans. Instrum. Meas. vol. 48, no. 2, pp. 422-426, 1999) allow the determination of electrical alternating current (AC) quantities (root mean square or RMS values, ratios and power) with unprecedented low uncertainties of the order of /spl mu/V/V and /spl mu/W/W. Extensive theoretical modeling of a system using this technique was done (W.G. Kurten Ihlenfeld, PTB Report E-75, 2001, and PTB Report E-76, 2001). Comparisons to validate the models are shown.