Novel Magnetic Field Modeling Method for a Low-Speed, High-Torque External-Rotor Permanent-Magnet Synchronous Motor
Round 1
Reviewer 1 Report
Comments and Suggestions for AuthorsOverall, this is a well-considered study on the design results of permanent magnet motors used for low-speed, high-torque operation.
1. Analysis was performed and considered to compare the three shapes of the pole arc. It would be nice to have an additional explanation of each size selection process. It is persuasive if you explain a clear reason for determining the dimensions of each of the three shapes.
2. What is the output (W) of this model? It appears to be a motor of several kW, and if you compare the rated efficiency, you can easily compare the energy saving effect.
3. What is the material and grade of permanent magnet used in this study? I wonder if the demagnetization characteristic has been taken into consideration and has no effect.
4. Isn’t the stator core in Figure 12 a rotor core?
Author Response
Thank you very much for your comment. Please see the attachment.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
Comments and Suggestions for AuthorsVery interesting paper and proposed approach. The experimental results are also impressive.
1) Abbreviations in abstract should be avoided by moving them into the text of the article.
2) Some formatting problems in the manuscript should be corrected, such as the superscript of some characters and the lack of space between numbers and units.
3) It is recommended to indicate the units for the variables presented in the equations.
4) In Section 3 did you assume the quasi-statics conditions for the magnetic field and negleting the saturation effect?
5) When using the method of separating variables it is possible to get analytial solutions for simple geometries and boundary conditions. Please indicate in which cases the use of numerical methods can be more effective for the magnetic field predition model?
6) Conclusions should be structured, highlighting the main obtained scientific and practical results, supporting them with quantitative information.
Comments on the Quality of English LanguageMinor editing is required.
Author Response
Thank you very much for your comment. Please see the attachment.
Author Response File: Author Response.pdf
Reviewer 3 Report
Comments and Suggestions for AuthorsDear Authors,
It was a pleasure to review your paper. Find below some observations regarding it:
1. The scope of the paper is not clear and its content seemly is not in line with the title. Most of it concentrates on comparing results obtained by using different analytical models with those obtained by FEA. Very few differences among them can be observed and there are no conclusions upon these results.
2. The state-of-the-art survey from the introduction should be improved. The cited references should be more deeply included within the paper text and compared more in detail. For example, you mention "Many optimization methods for PMs have been developed" but you are taking into discussion only two of these.
3. You should more detail the description of the (program used, mesh density, etc.),
4. Fig 6: in the center, you should replace the zoomed figure both for the quality increase and for including also here the color mad of the flux density (to see the saturated areas inside the motor)
5. The three cutting methods considered are displaying very close results. An advanced optimization method surely could much improve the characteristics of the electrical machine taken into study.
6. From the conclusion section you should delete those parts merely summarizing the content of the paper and to more focus on the general understanding obtained after conducting this research and providing the primary knowledge for extending it.
7. The revolution per minute should be abbreviated everywhere in the paper as r/min (upon SI standards) and not rpm.
Author Response
Thank you very much for your comment. Please see the attachment.
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
Comments and Suggestions for AuthorsThe overall content of the paper has been improved.
Author Response
Thank you very much for your comments and suggestions on our paper. We are grateful for your affirmation!
Reviewer 3 Report
Comments and Suggestions for AuthorsPractically, the pdf file with all the reviews is unreadable.
Till not understanding clearly the scope of the paper: to develop a new analytical method (why when FEA is so precise, fast, and easy-to -be used?) or to optimize a topology?
Till not knowing which software product you used for FEA.
Author Response
Dear reviewer,
Thank you very much for your comment and suggestion. Those comment are all valuable and very helpful for revising and improving our paper, as well as the important guiding significance to our research. The main corrections in the paper and the responses to the reviewers' comments are as follows:
Point 1: Practically, the pdf file with all the reviews is unreadable.
Response 1：
Thank you for your suggestion. We have uploaded a PDF version that accepts all revised content, and only those related to the reviewer's comments are highlighted in yellow.
Point 2 and Point 3: Till not understanding clearly the scope of the paper: to develop a new analytical method (why when FEA is so precise, fast, and easy-to -be used?) or to optimize a topology? Till not knowing which software product you used for FEA.
Response 2：
The authors are grateful to the reviewer for this comment. We will reply in two parts. We will explain the second part of Point 2 and the Point 3 together.
(1) The article proposes a novel modeling method that considers the edge cutting of PM. Therefore, in the revised version, we have modified the title again to better fit the content of the paper.
The new paper title is ‘A Novel Magnetic Field Modeling Method for Low-Speed and High-Torque External-Rotor Permanent Magnet Synchronous Motor Considering Permanent Magnet Edge Design’.
(2) We use the software 'ANSYS Electronics Desktop' to model and perform finite element analysis on the prototype. Due to the fact that the FEM can model completely based on the actual shape of the prototype. The results obtained are relatively close to the actual situation, so it can be said that the calculation results are accurate. During the modeling process, parameterized modeling methods can be used to adjust parameters using the system's built-in functions to achieve fast modeling, making it easy to use. However, the process of FEM is time-consuming, which mainly related to the size of the model and the grid density. The prototype studied in this article has a larger size, and in order to obtain accurate calculation results, a denser grid density is set, resulting in a longer simulation time.
Round 3
Reviewer 3 Report
Comments and Suggestions for AuthorsOK now!
Author Response
Thank you very much for your comments on our paper. We are very grateful for your affirmation!
