A Modified 2-DOF Control Framework and GA Based Intelligent Tuning of PID Controllers

Round 1

Reviewer 1 Report

In this paper, the author develops a tuning method for a 2DOF control framework involving conventional PID controllers based on genetic algorithms. The paper is moderately interesting, but must be improved before considering it for publication according to the following comments:

1. The author deals with the conventional PID control approach. As such the literature review is based on somewhat dated research papers, some of which date back to 1990s. It is suggested to revise the literature review to present more recent results thus obtaining a coherent state of the art.
2. The previous comment can be extended with the observation that the author completely ignores the topic of fractional-order PID control. So, in the state of the art, some relevant results pertaining to FOPID 2DOF control should be mentioned. A good overview of recent results can be seen in, e.g., [10.24425/acs.2018.125487]. The author is encouraged to study the reference and further study the references therein updating the present manuscript and its state of the art as needed.
3. The use of GA is, in general, not motivated well enough in the manuscript. There are other global optimization (GO) methods available, why should we use GA specifically? Please provide a firm motivation for your choice of GO algorithm.
4. The reviewer does not agree with the statement found in conclusions, namely: “The proposed method was applied to control the four virtual processes and its performance and robustness were compared with those of JIN-NPID, TK-IAE, and SG-IAE. The simulation results showed that the performance and robustness by the proposed method were much better than those of the other methods.” --- first of all, please define “much better”. Second, the performance due to the JIN-NPID tuning method seems to be quite close to the results stemming from the method proposed in the manuscript, and the former provides closed-form expressions for the tuning rules (so it is least computationally expensive). Please provide comments regarding this matter and provide a better motivation for the use of the method you propose.
5. The use of language is rather good, but still some proofreading ought to be done on the manuscript.

If the items above, especially 1 through 4 are considered, the revised paper may be accepted for publication.

Author Response

First of all, thank you for your careful review.

I tried to make every effort to make corrections during a short period of time.

I fully understand the points you made.

Revised details are described in the revised paper.

Respectfully yours.

Author Response File: Author Response.pdf

Reviewer 2 Report

Please, refer to the attached file.

Comments for author File: Comments.pdf

Author Response

First of all, thank you for your careful review.

I tried to make every effort to make corrections during a short period of time.

I fully understand the points you made.

The revised details are described in the revised paper.

Respectfully yours.

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

The Author have provided detailed explanations for the remarks raised in the Review process. I am suggesting accepting the manuscript for publication.