Ensuring the Accuracy of the Synchrophasor Measurement in the P Class Phasor Measurement Unit

In distributed relay protection and automation systems of power systems, the widespread use of P class phasor measurement unit is assumed. The accuracy of phasor measurements is affected by frequency variation of power system signals, the presence of multiple harmonics and the features of the electromechanical transient process. The necessary accuracy of phasor measurement in these conditions is provided by appropriate digital processing of electrical quantities. In this paper, theoretical and practical issues of digital signal processing based on the classical Fourier filter in a P class phasor measurement unit are considered. The purpose of the work is to obtain an algorithm for processing the input signal in a P class phasor measurement unit based on the classical Fourier filter that provides the necessary measurement accuracy. Materials and methods. When performing the work, the authors were guided by the regulatory documents. The methods of simulation modeling and mathematical simulation were used. Results of the work. The main result of the study is an algorithm for processing the input signal for a P class phasor measurement unit based on the classical Fourier filter, which ensures the correct measurement of the synchrophasor in static and dynamic conditions. The obtained algorithm for processing the input signal based on the classical Fourier filter can be used to create a P class phasor measurement unit. The algorithm obtained for processing the input signal in a P-class phasor measurement unit can also be applied to create M class unit by increasing the filtering properties. Conclusions. The algorithm for measurement phasor values based on the classical Fourier filter is presented. The operation of the method has been tested in static and dynamic conditions using simulation modeling and mathematical simulation, and the compliance of the method with the accuracy of measurement requirements of the phasor measurement unit of the P class was shown. The proposed algorithm can also be applied to M class phasor measurement unit by increasing the filtering properties.