Efficient fault identification scheme of compensated transmission grid based
on correlated reactive power measurements and discrete wavelet transform

Mohamed I. Zaki – Ragab A. El-Sehiemy – Ghada M. Amer

   The early fault identification in high-voltage power systems is a substantial aspect not only to minimize equipment failure but also to increase both the reliability and stability in power system. Subsequently, the aim of this paper is to propose the adaptive fault-identification scheme based on multi-resolution analysis technique. The proposed method is dependent on monitoring both voltages and currents from single-ended measuring system. The correlation among the reactive power computation and discrete wavelet transform is used to generate the significant criteria which are used to discriminate between short-circuit currents and energizing heavy loads behaviour. Different transmission network configurations are investigated to assess the dependability, security, and reliability of fault identification relay as well. The correlative protection scheme attains the accurate results under healthy disturbances, and therefore it is superior to other conventional approaches. In addition, a selective study is applied to different mother wavelets to find the best one. The response of the proposed scheme to the compensated transmission line is also verified at a wide range of compensation levels with faults before and after compensated bank. Simulation tests have been handled via ATP-EMTP to investigate the proper practicability and adaptability of the fault-identification relay.

Keywords: compensated transmission lines, DWT, fault identification

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