Load Frequency Model Predictive Control of a Large-Scale Multi-Source Power System

Round 1

Reviewer 1 Report

Overall impression: The paper shows weaknesses in scientific presentation and also with regard to formal criteria: The English is weak in terms of grammar, often articles are missing. Some errors like wrong capitalization, word repetitions, missing punctuation marks, missing verbs etc. suggest a hasty completion without sufficient proof-reading.
For example, both section 3 and 4 have the same title!
The numbering of the equations with three dots and brackets looks unprofessional and can be solved better.
A little more care would be desirable here - also out of respect for the reviewers.


Some ideas of the paper are quite interesting, as the state space representation (control engineering) is mixed with MPC (optimization methods) procedures. However, the scientific presentation needs much improvement.

First of all, the literature section contains numerous sources, which mainly refer to modeling techniques, without a clear reference to the case study at hand.

The case study at hand was described very inadequately, i.e. the connection between the theoretical part and the case study is very poorly presented and not comprehensible. Although the intro mentions clean coal plant and dual fuel gas turbines as major part of the case study, the description of how these are then modeled is very insufficient.

Illustrations are not sufficiently discussed and explained in the text.
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A few more specific comments on individual passages:

Figure 1. This is not discussed in detail in the text.  A source should be cited, even if it is a standard description. And the content should be described briefly, otherwise the picture can be completely omitted.

Equation 14 and 15: Why change from k to i?

Equation 19: What is now C_j?

Equation 25: Bracket protrudes into text

line 326: what is the difference between control horizon and prediction horizon?

Author Response

Please see the attachment.

Author Response File: Author Response.docx

Reviewer 2 Report

This paper presents a verified load-frequency Model Predictive Control (MPC), which aims to satisfy the load demand using three real generation technologies, which are wind energy, clean coal supercritical (SC) power plant, and dual-fuel Gas Turbine (GT). 

1. A general schema of your hybrid energy system should be presented clearly. Your figure 1 is directly a control schema (with simplified transfer function models), it is not a general schema to describe your studied system. Therefore, at the begning, it is better to use a general schema for the studied system, inculding energy storage, energy generation, and energy conversion., etc. 

 

2. From page 3 to Page 5, you just listed some research works in this domain. It lacks the integrity of your literature review. Yous should rewrite this part. 

 

3. Section 2 has presented some basic characteristics of state-space models. Also, you have presented the controllability and observability. These are in fact very basic points in the control engineering. You should present more examples of state-space modeling and its observability and controllability related to energy systems, such as the recent discussion about observability for the nonlinear state-space model of a kind of energy systems:  Lithium-Ion Battery Monitoring and Observability Analysis with Extended Equivalent Circuit Model," pp. 764-769, doi: 10.1109/MED48518.2020.9183112.

 

4. The presentation of MPC is similar to the section 2. The presentation is just some basic points about MPC. You can improve this part based on the direct application of your energy system. Namely, you present your studied energy system with state space modeling process firstly, then you introduce the MPC design process based on your studied model. 

 

5. MPC is a full-state feedback control technique, in your model (or studied system) should you estimate some system's states ? It seems that the application of MPC is simple for your system. 

 

6. Based on question 5, what's your main contribution in this paper ? Which contribution differs your research work from others ? 

 

Author Response

Please see the attachment.

Author Response File: Author Response.docx

Reviewer 3 Report

The author tried to solve the Load-Frequency Model Predictive Control of a Large-Scale  Multi-Source Power System.

The following points need to be clarified to improve the quality of the paper.

1.       How has the proposed method contributed to affordable energy resources, a cleaner environment, and sustainability ?? Justify

2.       How does the author claim that the state space models are simplified? justify

3.       How to overcome the frequency of excursions in case of higher penetration of wind power plants?

4.       The reviewer did not see the novel work in the paper as per your abstract

5.       The contribution stated in lines 176 to 193 seems to be vague.

6.       The expansion of the mathematical model is not properly explained.

 

7.       Validation of results is missing. 

Author Response

Please see the attachment.

Author Response File: Author Response.docx

Round 2

Reviewer 2 Report

The questions have been answered. 

Reviewer 3 Report

The author incorporated all the queries raised by the reviewer. The paper can be accepted in current form.