The object of research: processes of reproducing the parameters of a three-phase network of industrial frequency and their normative values in extended frequency ranges, alternating currents, voltages and phase angles with a given accuracy. The purpose of research: methods of theoretical electrical engineering and mathematics, methods of physical, mathematical modeling, mathematical apparatus of the Taylor and Fourier series, matrix calculus and numerical simulation on electronic computers. Methods of research: methods of theoretical electrical engineering and mathematics, methods of physical, mathematical modeling, mathematical apparatus of the Taylor and Fourier series, matrix calculus and numerical simulation on electronic computers. Theoretical and practical results and innovations: the components of the error in reproducing active and reactive powers and the asymmetry of a three-phase electric network are formalized, due to the imperfection of the metrological characteristics of the measuring power amplifiers (MPA), which made it possible to formulate the requirements for the limit levels of the individual components of the errors of the MPA and made it possible to obtain an increase in the accuracy requirements for reproducing the quality parameters of three-phase electrical networks; improved method for eliminating distortion of the alternating voltage of the output amplifier from non-linear load, which allowed to reduce the coefficients of non-sinusoidality of alternating voltages caused by non-linear circuits of measuring instruments; a new principle is proposed for constructing current and voltage sources on the basis of DACs, which differ in that they allow reproducing high current and high voltage with digital amplification by converting the input digital signal to the output signal by direct synthesis, which made it possible to use them in accurate, highly stable and automated means metrological support for measuring power and quality parameters of electric energy (EE); for the first time, a mathematical model of the MPA based on a high-voltage DAC (HVDAC) was created, with the help of which the advantage of the principles of its construction was proved and an amplifier was designed with a given accuracy of reproducing the amplitude of the alternating signal with the expected level of nonlinear distortion; a computer model of the MPA based on the HVDAC was developed, with the help of which a study of the metrological characteristics of the HVDAC was conducted, which confirmed the accuracy of reproducing the amplitudes of the variable signals and the coefficient of their nonlinear distortions obtained by mathematical modeling. A subject degree of introduction: measuring instruments using the technical solutions proposed in the thesis are introduced into serial production in the joint Ukrainian-Lithuanian enterprise "Elvin" in the form of a DNST-3k generator, a DNST-3 source, UAP-3, UAP-3M units and are used in organizations SС "Ukrmetrteststandart" and NEC "Ukrenergo". Effectiveness of implantation: a significant technical and economic effect has been obtained that consists in increasing the accuracy of reproducing the values of EE power and its quality indicators, the efficiency of calibration of measuring instruments and metering EE. Sphere of use: power industry, in metrological equipment for reproducing normalized values of EE power and its quality indicators and other industries.
