Study of the State Primary Measurement Standard of the Unit of Phase Shift Angle Between Two Voltages

Abstract

Phase measurements are necessary for determining main parameters of the oscillatory process in complex electrical networks. Most often, it is precisely the phase shift angle (PSA) between two oscillatory processes of the same frequency that is measured. An essential indicator of the quality of electrical energy is the coefficient of asymmetry in a three-phase electrical network, which depends on the load of consumers in this network. This indicator is affected by a short circuit between two phase voltages. Phase measurement standards, phase meters, and phase converters are included in the measuring equipment for phase measurements. They are widely used in such fields as radiolocation, radio navigation, non-destructive testing, radio engineering, telecommunications, acoustics, metallurgy, machine and aircraft industry, space industry, as well as in scientific research and defence. The State Measurement Standard of Ukraine of the PSA unit between two voltages in the frequency range from 0.01 Hz to 10 MHz is maintained at the State Enterprise “UKRMETRTESTSTANDARD”, Kyiv. It provides metrological traceability of phases measured in the country. The main components of the standard were calibrated at the PTB, the National Metrology Institute of Germany. In Ukraine, numerous measurement standards and measurement instruments for phase measurements (more than 500.000 units) are used, in particular, phase calibrators, phase meters, phase shifters, synchronoscopes etc. Regular study of metrological characteristics of the DETU 09-07-11 measurement standard is conducted both in the main (from 5 Hz to 200 kHz) and in the extended (from 0.01 Hz to 10 MHz) frequency range. The PSA values obtained as a result of the research in the main frequency range do not exceed 0.001° (which is maximum according to measurements at all calibration points 0.00015°), and in the extended frequency range – 0.01° (which is maximum according to measurements at all calibration points 0.0053°). To eliminate the systematic measurement uncertainty component of the phase measurement standard, a special calibration is regularly performed using a set of resistive and capacitive phase bridges.