Nonlinear Modelling and Control of a Power Smoothing System for a Novel Wave Energy Converter Prototype

Round 1

Reviewer 1 Report

Overall, this manuscript presents a supercapacitor bank and a unidirectional DC/DC converter based fluctuating power smoothing scheme. The idea is practical and interesting, and a series of theoretical analysis, simulations are conducted. The reviewer has the following comments and questions.

1, The contribution and the novelty of this work are better to be highlighted in the title.

2, How to get the results in Fig. 8?

3, What is the maximum power fluctuation that can be suppressed?

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

This research paper suggests the control of the electrical system of a Wave Energy Converter (WEC) prototype developed by SINN Power. To improve the paper, the authors may consider the following comments:

1.       Adding nomenclature will help the readers quickly understand the terms and symbols used.

2.       The introduction is not well articulated. The literature survey is not sufficient for proving the objective of this work.

3.       State the novelty of this work at the end of the introduction. After reading the full article, the reviewer felt that the authors' contribution is less.

4.       How can the DC-link voltage be controlled with the current through the DC/DC converter?

5.       Why is a unidirectional DC/DC converter used instead of a bidirectional DC/DC converter? As we know, a bidirectional DC/DC converter is better for controlling the generator units and reduces transmission losses.

6.       How do we encounter the change in DC-link voltage according to the fluctuating power?

7.       Please flowchart diagram must be introduced to understand the working electrical system of a WEC prototype.

8.       How is the battery current kept constant to increase the battery's lifetime?

9.       Why is the nominal voltage of 350 V chosen in this case?

10.    Please elaborate on the term p_esr mentioned in equation no. 10.

11.    The comparison is not enough for possible publication. The comparisons of the proposed control of the electrical system of a WEC prototype must be made with recently proposed WEC prototypes.

12.    Kindly include the experimental results for this research work. 

13.    In practice, the conditions of the sea are very versatile. Has the author tested the WEC prototype with other versatile conditions?

14.    Please check the grammatical mistakes carefully.

15.    Recent references must be included in the reference section.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

The authors have addressed all the concerns of the reviewer. Hence, I accept the article for publication in its present form.