Abstract
This paper presents a transient and non-unit-based protection scheme for consideration in DC grids of the future. The technique utilises the rate-of-change (R-o-C) of the associated travelling wave components following the occurrence of a fault to determine whether the fault is internal or external. For an internal fault, the product of the magnitude of the R-o-C of the fault induced voltage and current travelling wave following fault inception must exceed a predetermined setting, otherwise the fault is external. The DC inductor located at the cable ends provides attenuation for the high frequency contents of the fault generated components resulting from an external fault. The ratio between the forward voltage travelling wave and the backward voltage travelling wave provides directional discrimination. This ratio is less than unity for a forward directional fault and greater than unity for reverse directional faults. The protection algorithm has been validated using PSCAD/EMTDC simulations based on full scale modular multilevel converter (MMC)-based HVDC grid. The simulation results presented, including the performances indices compared to existing and proposed methods available in literature utilising the derivative of the fault induced components show the suitability and reliability of the proposed technique in distinguishing between internal and external faults. Key advantages of the proposed technique is that it simple, easily implemented, and does not rely on complex signal processing technique; and therefore it can easily be implemented to provide autonomous tripping for all relays located on the DC grid.
| Original language | English |
|---|---|
| Article number | 100195 |
| Number of pages | 25 |
| Journal | Sustainable Energy, Grids and Networks |
| Volume | 17 |
| Early online date | 14 Feb 2019 |
| DOIs | |
| Publication status | Published - 1 Mar 2019 |
Bibliographical note
NOTICE: this is the author’s version of a work that was accepted for publication in Sustainable Energy, Grids and Networks . Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Sustainable Energy, Grids and Networks, [17], (2019) DOI: 10.1016/j.segan.2019.100195© 2019, Elsevier. Licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International http://creativecommons.org/licenses/by-nc-nd/4.0/
Keywords
- DC grid protection
- Fault induced travelling wave
- Internal and external fault
- Rate-of-change (R-o-C) of travelling wave
- Transient based protection
ASJC Scopus subject areas
- Control and Systems Engineering
- Renewable Energy, Sustainability and the Environment
- Energy Engineering and Power Technology
- Electrical and Electronic Engineering