Measurement of Ac Voltages with Digital Voltmeters
نویسندگان
چکیده
A principle of using high-resolution digital voltmeters (DVs) HewlettPackard 3458A for the measurement of AC voltages in DCV range is described. The method of approximate synchronous sampling is used, having only one sample per cycle of a working frequency close to 16 Hz, when the mean value of one-third cycle is measured. The beginning of integration is shifted for the same interval for every subsequent period of the measured voltage. From the samples, the RMS value of the “derived” sine is determined using subsequent numeric synchronisation. The phase angle of the first sample of the “derived” sine is calculated as regression line coefficient. To ensure accurate phase difference measurement between two voltages, a synchronised triggering is used. A method for the determination of the difference between the sampling frequency of two DVs and the main frequency is presented. For the voltage ratio and phase difference measurements, the uncertainties of 0,1 ppm and 0,1 μrad respectively were achieved.
منابع مشابه
A 1Oppm ACCURATE DIGITAL AC MEASUREMENT ALGORITHM
Agilent Technologies as a company independent from Hewlett-Packard and describes products or services now available through Agilent. It may also refer to products/services no longer supported by Agilent. We regret any inconvenience caused by obsolete information. For the latest information on Agilent's test and measurement products go to: ABSTRACT Digital sampling has been used for a number of ...
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