Article Open Access http://dx.doi.org/10.26855/jepes.2025.06.003
The Prediction Method of Prior Time for Precise Synchronization in the Case of Varying Slip Frequency
Kwi Song An*, Kyong Il Pak
Faculty of Electrical Engineering, Kim Chaek University of Technology, Pyongyang 999093, Democratic People's Republic of Korea.
*Corresponding author: Kwi Song An
Published: October 10,2025
Abstract
The paper describes a synchronization method to reduce the closing time and prevent the impact on the generator in case of varying slip frequency. The most important problem in synchronization is to close the circuit breaker at the moment voltage, frequency, phase of the generator, and the power system are in coincidence. The accuracy of sync-check according to phase angle is an important factor for precise synchronization. Also, considering the input time of the circuit breaker, it is necessary to generate the output signal of the circuit breaker at a time prior to when the difference of phase angle becomes zero. But in the case of varying slip frequency, the calculated prior angle has a large error. This paper suggested a precise prediction method of prior time in case of slip frequency changes linearly and nonlinearly. Then, by using MATLAB/Simulink simulation, it was proved that the novel prediction method of prior angle reduces the synchronization time and the impact induced on the generator.
Keywords
Synchronization; Sync-check; Slip frequency; Prior angle
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How to cite this paper
The Prediction Method of Prior Time for Precise Synchronization in the Case of Varying Slip Frequency
How to cite this paper: Kwi Song An, Kyong Il Pak. (2025) The Prediction Method of Prior Time for Precise Synchronization in the Case of Varying Slip Frequency. Journal of Electrical Power & Energy Systems, 9(1), 18-27.
DOI: http://dx.doi.org/10.26855/jepes.2025.06.003