METHOD OF DETERMINATION OF PARAMETERS OF HARMONIC SIGNALS BY THEIR INSTANTANEOUS VALUES, MEASURED ONCE DURING THE PERIOD

Melent'ev Vladimir Sergeevich, doctor of technical sciences, professor, head of sub-department of information and measuring equipment, Samara State Technical University (244 Molodogvardeyskaya street, Samara, Russia), vs_mel@mail.ru
Pozdeeva Elena Vladislavovna, postgraduate student, Samara State Technical University (244 Molodogvardeyskaya street, Samara, Russia), yaelenkapavlenko@yandex.ru
Peskova Anastasiya Sergeevna, postgraduate student, Samara State Technical University (244 Molodogvardeyskaya street, Samara, Russia), yaelenkapavlenko@yandex.ru
Nefed'ev Dmitriy Ivanovich, doctor of technical sciences, associate professor, head of sub-department of information and measuring equipment and metrology, Penza State University (40 Krasnaya street, Penza, Russia), iit@pnzgu.ru

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Background. The subject of research is the method of measuring, based on the formation of two additional voltages and additional current, shifted relative to the input phase. The purpose of work is development and investigation of a new method determine the parameters of harmonic signals, the implementation of which includes simultaneous measurement of the instantaneous values of the input and additional signals once per period, that reduces the time of measurement.
Materials and methods. The approach to the determination of the parameters on the basis of the formation of additional voltage and current, shifted by an arbitrary angle relative to the input signals, and measuring the instantaneous values of the signals once per period is offered. In the analysis of error due to deviation of the real signal from the harmonic model, used a known method based on the estimation of uncertainty of measurement parameter, as a function, the arguments of which are assigned approximately with an error describing the deviation of the model from the real signal at appropriate points.
Results. A new approach to the determination of parameters of harmonic signals allowed us to develop a method that, unlike most known methods based on the formation of additional signals, eliminates frequency error of the phase-shifting units engaged in the generation of additional signals. The evaluation of the degree of deviation of the real signal from a harmonic model on the resulting error of the determined parameters are given.
Conclusions. Developed method of determining the informative parameters reduces the measurement time at the expense of single and simultaneous measurement of the instantaneous values of the signals. Obtained results allow to choose optimal parameters of the phase-shifting units engaged in the generation of additional signals, in accordance with the requirements in measurement accuracy.

parameters, harmonic signal, the instantaneous values, additional signals, the phase-shifting block, measuring time, error.