Stochastic Approach for Increasing the PV Hosting Capacity of a Low-Voltage Distribution Network^†

Round 1

Reviewer 1 Report

The manuscript uses a stochastic approach to calculate PV hosting capacity in a specific rural network situated in the Slovak Republic and focuses on the possibilities of increasing PVHC using low-cost and largely available tools for DSO. Although the manuscript provides some guidance for practical applications, there are some concerns regarding the details of the presented method as well as the organization of paper.

1） Although the main focus of this manuscript is the application of stochastic PVHC evaluation in real rural network, the contribution of this manuscript is quite limited.

2）Please revise abstract by including more details of potential challenges, motivations for your work, and key finding of submitted paper. It can cover following aspects: main idea of paper, key contribution and methodology, assumptions, and results.

3) Introduction can be improved by streamlining the length, retaining the literature review most relevant to the proposed method, organizing the logic to highlight the gap in current research, and clarifying the contribution of this paper.

4) The methods comparison and validation are lacked. To validate its superiority, the proposed method should be compared with similar approaches.

Author Response

Thank you for allowing a resubmission of our manuscript, with an opportunity to address the reviewers’ comments. We are uploading (a) our response to your comments and suggestions in following PDF file.

Author Response File: Author Response.pdf

Reviewer 2 Report

1) In Section 3.5, the values of overvoltage violation probability, undervoltage violation probability and voltage unbalance violation probability are given in the case. What are these values based on? How about the stability and security of the distribution network under these values of probabilities? Please elaborate on the reasons why using more conservative probabilistic limits can reflects more realistic needs of DSO？

2) In Figure 13b, 16 and 18 shows the voltage overlimit possibility curve is a smooth curve. But in the case of this study, the value of DPI is a discrete value ranging from 0 to 0.5 with an interval of 0.1. If it is fitted, what is the fitting method? Whether the fitting results are accurate?

3)In Figure 13d, only 5 experimental data are shown under 6 DPI values and the corresponding relationship with DPI values is not clear.

4) In 4.1, the results of scenario V0 show the voltage overlimit, power loss, power backflow and voltage imbalance of the distribution network. However, the limitations of PV carrying capacity mentioned in 1.2.1 above include voltage violations, voltage unbalance and harmonics, supraharmonics. Is it reasonable to conclude that the biggest problem in this particular network is overvoltage without analyzing harmonics, supraharmonics？

5) Is the stochastic PVHC modeling of PV and load parameters the innovation point of this study? If so, it is recommended to supplement the comparison of simulation effects and advantages and disadvantages with other models.

6) The innovation point is not prominent, the random method to calculate PVHC has been studied by others. The advantages of the method combining probability and deterministic input parameters in this paper are not proved by comparison. The methods of using PV power factors, DETC and BESS to improve PVHC have been studied for a long time. Please specify the innovation points.  

7) In 1.2.2, the study mainly introduces nine ways to increasing PV hosting capacity, but only three ways are analyzed in the case study. Could the content can be simplified in 1.2.2 or supplemented in the case study?

8) This study uses Monte Carlo method for random calculation. The more samples the Monte Carlo method takes, the more it approximates the optimal solution. However, in this paper, a grid consisting of 163 overhead power lines only used 100 samples. Does this guarantee the validity of the results? The reviewer would also suggest the authors supplement the computational efficiency analysis of this method. Can this method be applied to larger distribution networks with more sophisticated control methods by using the present limited computational power?

Author Response

Thank you for allowing a resubmission of our manuscript, with an opportunity to address the reviewers’ comments. We are uploading (a) our response to your comments and suggestions in following PDF file.

Author Response File: Author Response.pdf

Reviewer 3 Report

The writing of the paper is very poor. It must be improved

Author Response

Thank you for allowing a resubmission of our manuscript, with an opportunity to address the reviewers’ comments. We are uploading (a) our response to your comments and suggestions in following PDF file.

Author Response File: Author Response.pdf

Reviewer 4 Report

The paper entitled "STOCHASTIC APPROACH FOR INCREASING PV HOSTING CAPACITY OF The paper entitled "STOCHASTIC APPROACH FOR INCREASING PV HOSTING CAPACITY OF LOW VOLTAGE DISTRIBUTION NETWORK" describes a stochastic methodology for photovoltaic hosting capacity (PVHC) estimation and uses it to analyze a typical LV rural network in the Slovak Republic.

The references are adequate.

The authors presented a thorough investigation of the state-of-the-art and justified their methodology and scope.  

 

The manuscript needs proofreading. It is difficult for the reader to follow, in some cases, the text. I understand there is much information, but the sentences must be clearer. Logical and grammatical errors must be corrected.

Author Response

Thank you for allowing a resubmission of our manuscript, with an opportunity to address the reviewers’ comments. We are uploading (a) our response to comments and suggestions and (b) the updated manuscript.

The manuscript has been through extensive english editing.

Author Response File: Author Response.docx

Reviewer 5 Report

1. The topic of the research is important. The analysis is reasonably carried out.

2. Some points can be improved:

- The wind power plants are wide-spreaded RES and must be added to the list of DER in the Introduction (lines 17 -19),

- There are no references to the Figures 1 - 4 in the text. It must be added,

-  There is no sense to give the values of PVHC in percentage terms without to define  the variables used in the ratio (lines 94 - 102). It could be better to swap this paragraph with the next one ( (lines 103 - 115), 

- In the current edition of EN 50160 (EN 50160:2010+ Cor.:2010 + A1:2015 + A2:2019 + A3:2019)  harmonics up to 40th are considered for the calculation of THD in LV networks (lines 150 - 152),

- The time step  chosen for the simulations has no influence on the total duration of the 5% quantile in the time distribution. Only the requirements of the utility are decisive for the setting of 1% permissible violation  probability (lines 506 - 512),

- Figures should be referred in the text before they appear in the paper.  Please correct it.  

Author Response

Thank you for allowing a resubmission of our manuscript, with an opportunity to address the reviewers’ comments. We are uploading (a) our response to your comments and suggestions in following PDF file.

Author Response File: Author Response.pdf

Reviewer 6 Report

This is an interesting article in the field of low-voltage distribution networks. Also, the article is appropriate for the Processes journal. Although the manuscript is presented well, some minor revisions should be modified before publishing. The reviewer's comments are as follows:

1. The optimal data should be added between 2-3 lines at the end of the introduction section.

2.  I recommend adding at least 4-5 articles from the Processes journal to better show the relevance of the article to the scope of the journal. 

3.  The authors should be presented with a validation process and compare the results of previous work with their theoretical modeling. 

4. Please check again the English level of the manuscript to avoid any typos and grammar mistakes.

5. Please rewrite the Conclusion section and use the findings of this review article. In addition, it would be positive to get some future research suggestions on this topic.

 According to the above comments, the article needs some minor revisions. The article could be accepted if the authors addressed the above comments correctly.

Author Response

Thank you for allowing a resubmission of our manuscript, with an opportunity to address the reviewers’ comments. We are uploading (a) our response to comments and suggestions and (b) the updated manuscript.

The manuscript has been through extensive English editing.

Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

We thank the authors for the relevant notes and revisions. However,  the manuscript still has the following critical issues:

(1) The manuscript has poor novelty. The methods proposed and the conclusions obtained are not innovative in comparison with existing studies, which makes this paper insufficient to be published.

(2) The length of the manuscript continues to be lengthy. We recommend the authors to further reduce the length of the manuscript and retain only key information, especially in the introduction.

Author Response

Thank you for allowing a resubmission of our manuscript, with an opportunity to address the reviewers’ comments. We are uploading (a) our response to comments and suggestions and (b) the updated manuscript.

The manuscript has been through extensive english editing.

Author Response File: Author Response.docx

Reviewer 2 Report

Originality is  low.

Author Response

Thank you for allowing a resubmission of our manuscript, with an opportunity to address the reviewers’ comments. We are uploading (a) our response to comments and suggestions and (b) the updated manuscript.

The manuscript has been through extensive english editing.

Author Response File: Author Response.docx