Electric Drives: Complexes of Nonlinear Electromechanical Links Identified by Nonlinear Transfer Functions and Families of Frequency Characteristics

Round 1

Reviewer 1 Report

The paper “Electric drives: complexes of non-linear electromechanical links identified by non-linear transfer functions and families of frequency characteristics” is interesting for industry, and for science, because in my opinion it can contribute to developing of the many electric drives, as well as to increase its performances. In this regard, a method for taking into account the influences of nonlinearities on the electric drive characteristics, the method of nonlinear transfer functions and families of frequency characteristics, is proposed. In addition, the theoretical model of the theory of hyperstability is proposed, that it operates with boundary characteristics of nonlinear objects. The proposed method is aimed specifically at electric drives that use asynchronous electric motors, but may have a wider spectrum.

 

Following the review of the paper "Electric drives: complexes of non-linear electromechanical links identified by non-linear transfer functions and families of frequency characteristics", we can conclude that:

 

1. A correctly and also complete formulated nomenclature, which containing all the physical quantities and abbreviations involved in the paper along with the measurement units in the international system, is necessary to be introduced in the paper. Thus, the readers can more easily clarify physical quantities and abbreviations involved in the paper. This is because sometimes there is an inconsistency in the notations;

 

2. Regarding the Figure 1, the description of the figure does not contain all the notations and simbols involved. It is necessary to remedy these deficiencies of the paper by specifying all the notations and simbols involved in the Figure 1.

 

3. As regards the set of equations (1), it is found inconsistent in notations relative to the equation that characterizes the differential comparator, in the definition of the error Δ, as well as the incorrect definition of W_CU. It is necessary to remedy these deficiencies of the paper, because these notations must be correlated with those in Figure 1;

 

4. Regarding the Figure 3, should include sections (a) and (b). Then there should be a comment on section (b), in which we define the duty cycle factor and explain the symbol t. Also, it is necessary for the authors to improve the discussion regarding the the types of applications that are suitable for using pulses for control;

 

5. Regarding the relations (3), (4), (5) and Figure 4, it is necessary to present in the paper all the physical quantities involved;

 

6. Regarding the Figure 7, it would be desirable to reconsider the title of the figure. Also, Table 1 is invoked, which is not found at all in the paper;

 

7. In general, it is elegant that a paragraph does not end with a relation, i.e. (6), but with a comment. In this regard, is necessary to add a comment after relation (6). Also, regarding the relations (6), it is necessary to present in the paper all the physical quantities involved. It is also elegant that a paragraph does not end with a Figure, but with a comment. In this regard, is necessary to add a comment after Figure 12;

 

8. Regarding the Figure 8, please make legible the physical quantities corresponding to the abscissa in section (c);

 

9. As the authors themselves says, „The dynamic error ΔW will "work" in a much smaller frequency range, and its influence on the operation of the entire nonlinear system will be significantly weakened”. It is necessary for the authors to improve in the paper the discussion on this fundamental aspect;

 

11. Regarding the experimental results, the authors indicated in the paper only reference [14]. The paper remains at this level. It is necessary to present in the paper more experimental aspects. It is necessary for the authors to clarify this important aspect;

 

11. The conclusions of the paper must contain the possible implications of these study in future practical developments. What are the prospects for capitalizing on this research? It is necessary to add and these aspects to the conclusions.

 

Author Response

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Author Response File: Author Response.pdf

Reviewer 2 Report

1. The motivation and novelty of this work should be clearly highlighted;
2. Stability and robustness should be further justified;
3. An additional case studies for electric drives should be undertaken;
4. Future studies should be given.

Author Response

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Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Following the review of the paper “Electric drives: complexes of non-linear electromechanical links identified by non-linear transfer functions and families of frequency characteristics”, in this revised form we can conclude that:

The paper is interesting for industry, and for science, because in my opinion it can contribute to developing of the many electric drives, as well as to increase its performances. In this regard, a method for taking into account the influences of nonlinearities on the electric drive characteristics, the method of nonlinear transfer functions and families of frequency characteristics, is proposed. In addition, the theoretical model of the theory of hyperstability is proposed, that it operates with boundary characteristics of nonlinear objects. The proposed method is aimed specifically at electric drives that use asynchronous electric motors, but may have a wider spectrum.

I have looked carefully on the answers of the authors, regarding on all recommendations. In addition, I have looked carefully of the entire paper, in the present revised form. I think that the authors solved correctly and thoroughly the majority of the recommendations. However, some recommendations are necessary.

1. As regards the set of equations (1), due to an extra comma, an incorrect definition result for W_CU. Please remedy this deficiency;
2. It is necessary for the authors to improve the discussion regarding the types of applications that are suitable for using pulses for control;
3. Regarding the Figure 8, b, the equivalent circuit, it is necessary to indicate at the differential comparator level the "+" branch and the "-" branch;
4. Regarding the Figure 11, it is necessary to indicate at the differential comparators level the "+" branch and the "-" branch;
5. At line 356, please fill in the appropriate reference that is missing in the text of the paper.

 

 

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

acceptable

Author Response

Thank you for your review.