Wind Energy Harnessing in a Railway Infrastructure: Converter Topology and Control Proposal

Round 1

Reviewer 1 Report

This paper presents a power electronics approach aimed to harness the wind potential in a railway infrastructure. The topic is interesting. However, there are still many problems:

(1) There is too little elaboration on the research dynamics at home and abroad, so it can not explain the necessity and significance of this article.

(2) The explanation of the simulation results is too little and not deep enough.

(3) The research conclusions cannot well summarize the main research content and innovation of this article, and need to be revised.

Author Response

More research has been done showing the research gap in the application point of view.

Simulations have been improved and wider explanations have been added.

Conclusions have been explained deeper.

Reviewer 2 Report

The study shows his interest throughout the manuscript. Perhaps the authors, should make an effort to underline the impact of the paper, its usefulness for other communities or countries, etc. This aspect could be shown in the summary, in the conclusions or discussion.

The research has practical interest. However, I consider that there are important issues that should be improved, as explained below.

1. Abstract has inappropriate structure. I suggest to answer the following aspects: - general context - novelty of the work - methodology used - main results 

2. Introduction presents interesting information, but it is extremely poor with respect to other sections. I would suggest the authors to add other parts where the role of renewables and the related transition towards sustainability is discussed. This also looking at the most effective policy actions and private initiatives able to address energy and emission issue. See among the other:

https://www.sciencedirect.com/science/article/pii/S0301421517307012?via%3Dihub

https://link.springer.com/article/10.1007%2Fs10460-016-9737-9

Moreover, it would be interesting to have a focus on the role of stakeholders. See 

https://www.aimspress.com/article/10.3934/energy.2018.4.645

3. Methodology is unclear. Initially a short resume can be proposed to explain several steps

4. Results should be better linked to the methodology. Please define the relationship and relate your finding with the relevant literature.

5. Conclusion to be readapted after paper review.

Author Response

The abstract has been changed trying to answer those aspects.

The introduction has been widen, adding some research from the point of view of renewable energy sources and policies among emissions.

A resume has been added to explain the methodology.

Conclusions have been changed.

Reviewer 3 Report

Dear Authors,
interesting article, but it is to be completed. The idea is not new on the use of wind energy moved by a train, there are several patents and ideas.
What is missing is to be improved in the following paper:
1) Boost control MPPT: it is fine to table all the control algorithms, but in (Figure 3) and in the simulation it is not clear which one is used.
It is also unclear because you have used a "three-phase diode bridge rectifies", instead of a much more efficient "Fully-controlled 3-phase Bridge Rectifier".
with the possibility to regulate the DC bus.
2) The description of the control implemented for "Isolated DAB" is missing.
3) Figure 2: insert the capacitances on the DC lines (it serves to make it clear that the voltages are leveled)
4) Figure 3 and Figure 5: For (Vin, Iin, etc.) use subscripts when writing the voltages and currents, to make the paper more readable.
5) Paragraph "Model and simulation results": before the simulation insert a table summarizing all the input and configuration data used.
Also, describe all the model blocks before simulation, then you can show the results.
6) Figure 8: In the current graph, such a high ripple can "destroy" the DC-link capacities. Make the appropriate checks in the "control" system
Best regards

Author Response

The MPPT technique used is the HCS, which is now clearly pointed out. The use of the diode bridge and boost converter is due to add robustness and simplicity to the control, which are essential features in small wind turbines.

The SPS technique is pointed out and explained in figure and text.

Added capacitances in buses to show voltage stability.

Changed to subscripts some parameters in figures.

A parameter table of the whole model has been added.

The current ripples have been reduced as shown in the new figure.

Reviewer 4 Report

- what is the novelty of this paper?
- present in the Introduction other researchers work related to the subject;
- what are the components of the model?
- what are the data for the model and the simulation?
- what software was used for the simulation?
- how is the control implemented in the model?

Author Response

All the question have been addressed in the new version.

Round 2

Reviewer 2 Report

All comments have been properly addressed.

Author Response

Introduction has slightly changed.

Reviewer 3 Report

Dear Authors, the paper is now much better.

Read carefully and review the position of the Figures in the corresponding paragraph before conclusions.

Best Regards

Author Response

Introduction has slightly changed and figures are ordered.

Reviewer 4 Report

- present in the Introduction section the novelty of this paper;
- Figures 9, 10, 11 and 12 should be placed before the Conclusion section.

Author Response

Introduction has slightly changed and figures are ordered.