Transmission Line Voltage Calibration-Free Measurement Method
Round 1
Reviewer 1 Report (Previous Reviewer 1)
Main limitations of the proposed method, described in my previous reviews, are not answered.
Author Response
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Reviewer 2 Report (Previous Reviewer 2)
I previously review this paper (as electronics-1968590). All my comments were applied. I still keep my previous decision to accept this paper.
Best regards,
Author Response
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Reviewer 3 Report (New Reviewer)
Yang et al. submitted the paper titled, “Transmission line voltage calibration-free measurement method” in Electronics. this paper proposes a calibration-free transmission line voltage measurement method. This method has the advantages of high precision and calibration-free in the ungrounded sensor probe through equipotential and differential input structure, which can effectively solve the problem of insulation and installation scene limitation. I recommend the authors address the following comments for improvement. It requires a major revision.
· Please provide some quantifiable data in the abstract and conclusion sections. The conclusion section can be further improved. In the abstract, there is redundant information that is not required. It should be concise focusing on the data proposed in the current study.
· Sections 2.2 and 2.3 both are “principle of floating ground sensor.” Please clarify.
· Can the authors provide further details about the capacitor?
· Please explain the selection criteria for using different types of conductors and how these are influencing the voltage.
· In Table 1, please add an extra column for the references.
· There are no Figures 1a and 1b. Please rectify the errors in the text. Please also define all the components used in the circuit equivalence diagram.
· Please check the captions of all the figures and tables. It should be consistent (e.g., superscript, subscript, bold, font size, etc.)
· The language of the paper requires the utmost attention. There are several typos, mistakes, and consistency flaws.
Author Response
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Author Response File: Author Response.pdf
Round 2
Reviewer 3 Report (New Reviewer)
I am satisfied with the answers. It can be accepted now.
This manuscript is a resubmission of an earlier submission. The following is a list of the peer review reports and author responses from that submission.
Round 1
Reviewer 1 Report
Floating ground measurement is of great importance for the industry. The development of new methods that are more accurate and more convent to be installed on the measurement sport are on huge demand. The submitted article by Yang et al. presents one approach that is based on the reduction of the five capacitance model. The presented paper is interesting but in humble opinion of this reviewer it has some critical issues that must be addressed:
1. English language is very poor and complete text must be carefully rewritten. A few examples:
- the line before Eq. (4): “When the capacitance is Q:” but there is Gauss law for dielectrics
- the first line after eq. (8): “The formula is the dielectric constant of the insulating medium”, which is totally unclear and unrelated to the text
- the line after fig. 7: “the entire sensor is equal to the charged wire”, how sensor can be equal to the charged line?
-subsection 3.1: “the outer plate of the sensing probe is not directly grounded, but through its own electric field coupling with the earth to form a spatial coupling capacitance grounding, which can effectively solve the above problem of limited installation position.”
- page 11, subsection 4.3: “Build the experimental platform as shown in the following figure to test it”
2. Introduction should be rewritten. I suggested to authors to create a table in which they will summarize key limitations of the state of the art and clearly indicate research gap that this paper will answer.
3. Paragraph above Fig. 1: “Therefore, both IVT and CVT have the practical problems of large volume, limited installation position, effective grounding and measurement of signals with the help of low-voltage instruments.” This must be elaborated in more details with confirmation from references.
4. Paragraph after Fig. 1: references should be placed at the end of the sentence.
5. do not mix terms earth and ground.
6. Page 5: “In the simulation, the voltage ratio error is quantified by changing the eccentric distance of the probe, the insulation thickness of the live wire and the wire diameter. In this paper, only the influence of the variation range of the capacitance on the voltage ratio is studied.” Why and what are the consequences if only the influence of the variation range of the capacitance on the voltage ratio is studied?
7. Among most important comments: Sentence before section 3: “Therefore, we often reverse the voltage division ratio by online calibration, which will lead to the installation and measurement of the voltage sensor always in a fixed position.” Why this is a problem when authors suggested in the first paragraph in description of their method (subsection 3.1): “Firstly, the inner plate of the sensing probe is in direct contact with the wire to be tested, so that the inner plate and the wire to be tested form an equal potential.”
8. What are requirements for the used oscilloscope in terms of sampling rate, etc.?
9. Figure 13 is not referenced in the text.
10. Fig. 14 has label oscillograph instead of oscilloscope.
11. Critical: measurements were performed without comparison against reference measurement device, therefore there is no accuracy discussion.
12. Critical: measurement resolution is not defined
13. Authors must clearly indicate the novelty of this work.
Author Response
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Author Response File: Author Response.pdf
Reviewer 2 Report
Paper presents a detailed theoretical and simulation analysis of the three factors affecting measurement accuracy and designs a middle-limit device for the factors of eccentric distance. Additionally, in paper, a new measurement voltage scheme is proposed, which simplifies the thefive-capacitance equivalent model in the non-intrusive measurement system, and the constructed two-capacitance model possesses a constant voltage division ratio. It's important to notice that the results are validate by the experiment. So the range of the research presented in paper is interesting. This topic is actual. Electronics journal is correct selection for this type of research.
My recommendations to improve paper;
-> at least 9 positions should be added to the literature review. Please use only the 2020-2022 year to reach 30 positions in total.
-> between 2. Principle of non-intrusive voltage sensor and 2.1. Five capacitance model principle please add a general introduction to section 2. The same recommendation for 3. Principle of New Voltage Measurement System and 3.1. Establish equipotential model as well as 4 Experimental analysis and 4.1 Back-end circuit design
-> please do not include the very easy and well know equations such like eqs 4-7. It's review paper not a book for students.
-> in conclusion also please add a future research direction in this field.
Author Response
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Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
I feel that the authors were rushing on solving reviewers' questions. In my opinion, this manuscript is not well-prepared and well-organized. I still do not think the quality of the answers and the paper in overall are decent enough to be published in MDPI Electronics. From the current state of the work, it is apparent that the work is still in its early stages of development. Perhaps, the authors can submit the manuscript to a conference to disseminate this work and may consider submitting it to journal with impact factor when the work is at a more refined stage.
Reviewer 2 Report
Paper has been correctly revised.
