Research on Characteristics of Copper Foil Three-Electrode Planar Spark Gap High Voltage Switch Integrated with EFI

Round 1

Reviewer 1 Report

Comments:

The topic looks interesting. “Experimental study on characteristics of three-electrode planar spark gap high voltage switch based on copper foil” a three-electrode planar spark gap high-voltage switch based on copper foil was designed. In the present form, there are some issues that need clarity. For improving the quality of the paper, the authors can address the following comments:

1. In the abstract, the reviewer would like to see the method and significant of the findings.
2. In the introduction, Can the authors include a paragraph about the paper organization?
3. There are not enough literature review studies. Can author provide table and summaries at less 10 latest studies on the topic?
4. However, paper title talks about an experimental study. In section 2 the author resent a simulation work.  In section 3, the fabrication and test are presented. The question why you include the simulation work?
5. Figures inset need to be clear and same text font.
6. References are less
7. The paper can be improved. The review study in the introduction can be more. Then reviewer suggest having a discussion section to understand more about the study.
8. Figure during testing can be included in the paper
9. The test voltage can be stated in abstract and conclusion
10. Discuss what is the highest voltage you can use in your test?

Comments for author File: Comments.docx

Author Response

Thank you very much for your valuable comments and suggestions, According to your suggestions and comments, this paper has been greatly revised, please review the revised manuscript again, thank you!

 

Author Response File: Author Response.docx

Reviewer 2 Report

1. The industry significance of the topic of the study is not clear.
2. The introduction cites 18 references but failed to present the state of the art, novelty of the present work.
3. Authors need to bring the introduction section to a standard that is acceptable in the technical publications.
4.  Figure 1 is too fundamental and all the measurement/geometry details may be included. This will improve the technical view of the figure.
5. Authors: "The radius of positive 72 and negative main electrodes is 2.5 mm. the distance b is 2.0 mm and the width of trigger 73 electrode a is 1.2 mm", How did the authors arrive at these conditions. 
6. Can the authors present the quantitative analysis of the Figure 2 and 3.
7. A strange red font in line 121.
8. Eq. 1 is very very fundamental.
9.   A common methodology section for the simulation and experimental studies will avoid confusing readers. 
10. From Table 1: seeing b/mm and error, what conclusions one may draw. the same is the case with a/mm
11. The present paper is in the form of a technical report, this need a good organisation of the contents for an appropriate representation in the scientific publication. 

Author Response

Thank you very much for your valuable comments and suggestions. According to your suggestions and comments, this paper has been greatly revised. Please re-review the revised manuscript, thank you very much!

Author Response File: Author Response.docx

Reviewer 3 Report

The Authors present the design of a planar, three-electrode switch based on copper. The behaviour of such a new sputtered switch has been tested, showing a wide operational voltage strength. Nonetheless, the manuscript in its present form lacks in several,major, aspects:

The overall description of the results is merely qualitative, although some data have been exposed in tables, there is a number of words (such as increase, decrease) that only provide a rough and not comparable idea of the improvements provided by the switch. Conclusions have been written accordingly. 

The overall reading of the manuscript is awkward, with a significant number of repeated words, repeated concepts and misses of revision and care on details (see also below). The first paragraph of page 6 "As shown in Fig. 7..." it was impossible for me to be red. The same for paragraph 3.3.3, where part of a sentence is likely missing.

Getting into scientific details, the units of the breakdown strength air are not common: it is generally expressed in KV/cm and non in KV/mm. In any case, the reported data are wrong, since such value is roughly 30 KV/cm and not 30 KV/mm as written (cf. Hogg et al., 2013 19th IEEE Pulse Power Conference) and also your work: in figure 2 and 3 the measured data are in the order of 10^6 V/m, which results in 10^1 KV/cm. Moreover, it looks weird to me the following data provided in km/mm. Please, read the manuscript before submitting it.

Data coming from figures 5 and 6 are simulated, I guess? Please, add that in both legends.

Why the errors provided in Table 1 do not have a monotonic trend as a function of the increasing voltage?

Some other minor, although important, typos can be found in the overall manuscript, such as USB (page 8)

 

Author Response

Thank you very much for your valuable comments and suggestions. According to your suggestions and comments, this paper has been greatly revised. Please re-review the revised manuscript, thank you very much!

Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

1. The author did not highlight the changes in the paper due to reviewer comments, but the improvement are clear to the reviewer.
2. The abstract and conclusion are too long. The authors can summaries some sentence.
3. The paper presentation is well prepared in this Version.
4. Please check the references style 

Author Response

I am very grateful to the reviewers for their affirmation of this paper and for their valuable comments and suggestions. According to the comments and suggestions put forward by the reviewers, the paper was re-revised. In response to the comments and suggestions put forward by the reviewer, the revised content is as follows.

1. The format of the references has been revised as required by the journal;
2. In order to make it easier for readers to understand the background, purpose and significance of the research, the development of high-voltage switches for EFI is reviewed in detail in the introduction part, and I am very grateful to the reviewers for their valuable comments!

Author Response File: Author Response.docx

Reviewer 3 Report

Although the improvements on both introduction and 1st part, where data have been more extensively included in the discussion of the results, some major flaws still persist in the present version. In particular, I must insist on the discussion of the Figure 14 (previously Figure 2), in which units are still non-coherent and even the sentences "...the value of 2.29 kV/mm, which is 30 kV/cm lower than the breakdown strength of air. Considering that the air in the test environment is not ideal, the breakdown strength of air will be lower than the ideal value of 30 kV/cm..." do not make sense at all: if the value that the Authors reported is 30KV/cm lower than the actual breakdown strength of air, which is 30KV/cm, the difference would be equal to zero.

Author Response

I am very grateful to the reviewers for their affirmation of this paper and for their valuable comments and suggestions. According to the comments and suggestions put forward by the reviewers, the paper was re-revised. In response to the comments and suggestions put forward by the reviewer, the revised content is as follows.

 

Figure 14. Electric field distribution before triggering.   

Figure 15. Electric field distribution after triggering.

As shown in Figure 14, when a high voltage of 1.3kV is provided between the two main electrodes of the switch, the electric field is evenly distributed between the two main electrodes, and the field strength near the edge of the trigger electrode is the largest at 22.9kV/cm. At this time, the maximum field strength is lower than the breakdown strength of air by 30kV/cm, so the switch cannot self-breakdown. Considering that the air in the test environment is a non-ideal environment, the breakdown strength of the air will be lower than the ideal 30kV/cm due to factors such as humidity and temperature. In order to improve the safety of the switch, it is necessary to reserve a certain distance to ensure the insulation effect and avoid false triggering. As shown in Figure 15, the trigger electrode was applied with a voltage of 1.5kV, and the maximum electric field strength between the trigger electrode and the cathode reached 52.5kV/cm, which was 30kV/cm higher than the breakdown strength of air. At this time, the gas between the trigger electrode and the cathode will be ionized, and electrical breakdown will occur, so that the main electrodes will be broken down, and the conduction loop will discharge. In order to improve the working reliability of the switch, when the trigger voltage is loaded, the minimum electric field strength between the two main electrodes and the trigger electrode must be higher than the breakdown strength of air by 30kV/cm.

 

Author Response File: Author Response.pdf