Linear Programming Coordination for Overcurrent Relay in Electrical Distribution Systems with Distributed Generation

Round 1

Reviewer 1 Report

The reviewed article is a really good engineering job. The structure is correct, the literature review is quite extensive. The subject matter presented in the article is interesting and up-to-date. Unfortunately, I have a lot of comments about the editing and editorial side.

General comments:

• In my opinion, using abbreviations in the title of an article is not a good idea. Instead of DG, I would simply replace Distributed Generation
• Throughout the article, for references to two or more references, commas are missing between individual references, e.g. Line 43: „… devices have been discussed in different literature [4] [7].". This is consistently used throughout the article, except for a few obvious editorial errors, so it is acceptable, nevertheless I believe that the comma is the better solution.
• I find figures 2, 4, 5, 7 and 9 to be difficult to read. The content of the article (lines 136 and 137) shows that the original figures are in color. Maybe then they would actually be more legible. Especially the marking and description of the axle are illegible.
• Figures 10 and 11 are possibly damaged and this is the main reason why I believe the article needs to be revised.

Detailed comments:

• Line 34: „…  protection system is achieved [1]. [2]." - redundant dot after [1].
• Line 40: „… be less effective. [1] [5]." - redundant dot after "effective".
• Line 76: "2.1.- Loss of sensibility" - edundant dash before "Loss". The text of the article uses the term "sensitivity", in the title of the chapter "sensibility". Isn't it worth standardizing it?
• Line 86: "... RC the automatic recloser and FUS is a protection fuse for the branch line". – In the figure, the fuse is labeled F, not FUS..
• Lines 91, 92: For faults located upstream (between the substation, S, and the DG)" – In the figure, the station is labeled S.E., not S.
• Line 94: "In the operating characteristic curves of the time over current ..."– Shouldn't it be overcurrent?
• Line 95: "...the current detected by the relay (R, in the figure)..." – in the figure relay is labeled RELAY, not R.
• Line 96: "...regardless of the level of penetration level of the DG.."
• Line 102: "...the main relay, R, of the ES to decrease from..." – What is ES?
• Line 116: "Short Loss of sensitivity substation relay. Loss of sensitivity." - In my opinion, the repetition of "Loss of sensitivity" is unnecessary. - 
• Lines 136, 137: (red line), (green line) – I only see black lines. Perhaps they are colored in the original, which probably improves the legibility of the figures.
• Line 195, 196: Markings ti;min and ti;max other than in formula (3). Here's a semicolon after the ti, there's a comma in the formula.
• Line, 202 203: Inconsistent use of semicolon and colon.
• Line 203: The end of the dot is missing.
• Line 212: The colon is missing.
• Line 214: "For inverse characteristic curves it is usual α=0.02 and β=0.14 [47]. [46]." - redundant dot after [47].
• Line 216: Inconsistent use of semicolon and colon.
• Line 227: "The power demand of the electrical loads connected to the network is 12..."- 12 MW?
• Line 304: shown in Appendix Tables A1 and A2. and, Table A3, this one, shows – redundant dot after A2.

Author Response

Dear reviewer, please find enclosed the answers to your questions.

Author Response File: Author Response.pdf

Reviewer 2 Report

The submission presents the Research on Linear Programming Coordination for Overcurrent Relay in Electrical Distribution Systems with DG. However, there are certain issues that the authors should be clarified and improved upon:

1. Add the Nomenclatures and Abbreviations in order to improve the quality and readability of the manuscript.
2. Improve the English writing/editing of the manuscript. There are many grammatical mistakes throughout the manuscript. Moreover, improve the quality of the figures and discuss what they represent.
3. The introduction is vaguely written. My suggestion is to divide the introduction into three subsections: 1) motivation and incitement, 2) literature review and 3) contribution and paper organization. Moreover, the authors should compare their study in greater detail for differences that might explain their opposing findings by highlighting the goal and the novelty of the manuscript in the Introduction with 3-4 bullet points.
4. The abstract should briefly display the results of the research.
5. The conclusions should be supported by the research data so that it is a sharper one.
6. It is necessary that the authors should illustrate/present the modeling/design and data of the studied system, system constraints/data/parameters, etc. Moreover, state the system constraints, in other words, the upper and the lower boundaries of the system variables, etc.
7. Add more results to validate the proposed work and compared those with the existing analysis/work.
8. Present the details of the proposed work. The mathematical formulations are not clear and didn’t discuss properly.
9. The computational effort and accuracy of the proposed work should be compared with other existing techniques to justify its effectiveness.
10. A similar type of work has already been published in the previous literature. Then what is new in this work. The authors must clearly state the novelty of this research.
11.  

Author Response

Dear reviewer, please find enclosed our answers to your questions.
Kind regards

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

The article has been significantly improved. Especially the legibility of the figures is much better than in the original version. I have only one minor editorial note.

Line 50: "others recommend reconfiguring the network topology, [12,13], or the use". In my opinion, the comma after "topology" is redundant.

Reviewer 2 Report

The authors have done great work.