The Single-Phase Voltage and Power Control Algorithm of a 4-Leg Type CVCF Inverter for an Off-Grid Micro-Grid System

Round 1

Reviewer 1 Report

Although the manuscript promises further contribution, some serious lacks are appeared as follows:

1) Reporting results based on a calculated study, even if a computer code is used, must include a discussion on the calculated accuracy. Benchmark solutions are important tools for analysis to assess the accuracy of the calculated method that used, and to validate with the practical implementation. The capability of the numerical solution should be examined in a clear way, including boundary conditions and initial conditions in each numerical condition. The accuracy of implementation of boundary and initial conditions should be fully examined. Formal order of accuracy should be given  by assessing the convergence, also the code independence test, and the capability of capturing the solution. Without this sequence step, the present result becomes questionable.

2) More comprehensive description between Figures 10-12 to proof the calculated results. Elaboration using the relevant published works is required (see Refs. 4, 13-17). Elaborate please why this is happening. Authors need to discuss in detail more studies that focus on the objective of the research through comparison and evaluation the determinants of those studies and their results, which gives the reader a clear visual of the gap that those studies have not address and covered by this present work (based on the present result).

3) Point (2) of the Conclusion (Line 277) needs a more equitability discussion based on the results.

4) Language expression must be improved imperatively throughout the manuscript. Many sentences should be rewritten due to the lack of coherence and too many confused sentences in meaning. 

5) No need further discussion in the conclusion section, however, a more comprehensive discussion is required (see points 2-3).

Author Response

Thank you for your review.

Please see the attachment.

Author Response File: Author Response.docx

Reviewer 2 Report

As the existing control algorithms are not enough to operate the 4-leg CVCF inverter in stable manner, in this paper, the authors proposed a single-phase voltage and power control algorithm of 3-phase 4-leg CVCF inverter based on dq control in order to improve the unbalanced voltage problems caused by severe unbalanced load. Here are the detailed comments,

1. As there are numerous previous research on this field of research, the novelty of this study should be further emphasized. What are the main innovation points in this work?
2. Only these conditions are considered. Are they representative?
3. Can the control algorithm be used for other conditions?
4. Some figures are difficult to be understood, and it should be revised to become clearer.
5. Language editing should be made carefully.

Author Response

Thank you for your review.

Please see the attachment.

Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

I have no further queries.

Author Response

Thank you very much for reviewing this paper.

Reviewer 2 Report

The authors have replied my comments properly. And I suggest acceptance of this paper.

Author Response

Thank you very much for reviewing this paper.