Open AccessTransient‐based protection technique for future DC grids utilising travelling wave power
Author(s) -
Ikhide Monday,
Tennakoon Sarath,
Griffiths Alison,
Ha Hengxu,
Subramanian Sankara,
Adamczyk Andrzej
Publication year - 2018
Publication title -
the journal of engineering
Language(s) - English
Resource type - Journals
ISSN - 2051-3305
DOI - 10.1049/joe.2018.0186
Subject(s) - transient (computer programming) , fault (geology) , power (physics) , time domain , computer science , electronic engineering , traveling wave , electric power system , electrical engineering , engineering , physics , mathematics , geology , mathematical analysis , quantum mechanics , seismology , computer vision , operating system
This study presents a novel time‐domain protection technique for application to DC grids. The technique utilises the power developed by the forward and backward travelling waves produced by a fault to distinguish between internal and external faults. For an internal fault, the calculated travelling wave power must exceed a predetermined setting; otherwise the fault is external. The ratio between the forward travelling wave power and the backward travelling wave power provides a directional comparison. For a forward directional fault, this ratio is less than unity, whereas the ratio is greater than unity for reverse directional faults. To improve the sensitivity of the protection scheme for long‐distance remote internal fault, a second element utilising the concavity of the forward travelling wave power is proposed. The proposed technique is time domain based and does not require complex mathematical burden; moreover, as such can be easily implemented since it will require fewer hardware resources. Simulations were carried out in power systems computer‐aided design/electromagnetic transient simulations, and the results presented considering wider cases of fault scenarios including 500 Ω remote internal fault shows the suitability of the proposed scheme as all fault scenarios indicated were identified within 500 µs following the application of the fault.