Power systems
Iman Mousaviyan; Seyyed Ghodratollah Seifossadat; Mohsen Saniei
Abstract
This study introduces a single-ended method to detect the protection zone and distinguish faults occurring in the back of the relay in the transmission lines and then provides an algorithm to classify different types of faults, including a lightning strike on phases and shield wire. Accordingly, using ...
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This study introduces a single-ended method to detect the protection zone and distinguish faults occurring in the back of the relay in the transmission lines and then provides an algorithm to classify different types of faults, including a lightning strike on phases and shield wire. Accordingly, using the Wavelet Transform (WT), the first class of Traveling Wave (TW) current is separated at the beginning of all bus-connected lines. The faulty line and the protection zone are selected based on the relations governing the radiation and reflection. Then, given the features and relations extracted from these waves, the faults caused by lightning strikes on the transmission line and conventional faults are classified, with considering the mutual induction between TWs on the transmission line phases. This action is essential and helpful for transmission line with single phase tripping and auto-reclosing mechanisms. Over 1100 faults with varying conditions and locations are implemented on a 100-km line with a voltage level of 230 kV in the PSCAD software to evaluate and test the proposed method. The results of this heavy simulation confirmed the validity, speed, and accuracy of the proposed method.
Power systems
Mohammadreza Noori; Seyed Ghodratollah Seifossadat; Alireza Safarian
Abstract
In this paper, a novel selective DC fault detector approach based on the adaptive cumulative sum method (ACUSUM) is suggested for the protection of high voltage direct current (HVDC) transmission lines. Using a communication channel, the proposed method detects DC fault occurrence as well as determining ...
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In this paper, a novel selective DC fault detector approach based on the adaptive cumulative sum method (ACUSUM) is suggested for the protection of high voltage direct current (HVDC) transmission lines. Using a communication channel, the proposed method detects DC fault occurrence as well as determining faulty line at a multi-terminal HVDC (MT-HVDC) transmission system; the whole in less than 2ms. The suggested approach works in the time domain and employs the ACUSUM method as a mathematical tool for detecting abrupt variation at the magnitude of lines current for fault detection. Simulation results confirm the selectivity of the proposed algorithm at different DC fault situations which enhances the reliability of the power system. Besides the low sampling rate, the ACUSUM calculation burden is very low and its implementation needs no special or complicated hardware. Rather than appropriate speed, adaptivity, independence from system parameters, robustness against fault resistance, fault distance and noise are significant advantages of the proposed algorithm in comparison with other methods. adaptivity, independency from system parameters, robustness against fault resistance, fault distance and noise are significant advantages of the proposed algorithm in comparison with other methods.
