Arc Quality Index Based on Three-Phase Cassie–Mayr Electric Arc Model of Electric Arc Furnace

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

Please address these points:

1. Provide clear aims, methods, results and some conclusions in the abstract.

2. Explain how this article is original research and not just theory.

3. Explain what is the case/materials you tested empirically to gain results and explain the results.

4. Provide much more references in the discussion section.

5. Check your whole article again and provide a clear empirical case that you have studies starting from aims, materials and methods, results, broad discussion and conclusions based on your study.

Comments on the Quality of English Language

Some minor editing is needed.

Author Response

Please see the attached response to the reviewer and the tracked changes.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

The research carried out by the authors is interesting and has a perspective. The manuscript is well written. I have checked all the formulae and have found no mistakes (some remarks are at the end of the review). However, in my opinion, there are some points that you can address to improve the manuscript:

 1)     You should include basic EAF parameters, e.g., rated power. Taking into account the length of the cycle (1000 s), I assume that the EAF size is rather small.

2) I think the weak point of the AQI definition is that you must individually set parameters k and k0 to achieve AQI range between 0 and 100%.

 

Moreover:

a) Equation (13): remove ‘+’ at the beginning of the right side.

b) Line 416: ‘where the initial state is12(0) is defined as the real part of Im12(0)’ – Im12 is a phasor, so this notation is not correct from the mathematical point of view. It is enough to remove the argument ‘(0)’ or to introduce the associated function Im12(t) for the phasor Im12 using exp(j w t). Additionally, it should be multiplied by the square root of 2 if you use RMS voltage and current values (not peak) in equation (36).

c) Equation (37) is true only for real part (denominator) greater than zero – if it is less than zero, you must add Pi (for imaginary part greater than or equal to zero) or subtract Pi (for imaginary part less than zero).

d) Line 513-514: ‘We also assume that the ideal RMS value of the arc resistance RRMSopt is the minimum of the realizable resistance and have therefore set it to zero’. It is rather the lower limit of the assumed range and for sure not the minimum of the REALIZABLE resistance (resistance 0 is not realizable, it is an ideal case).

e) Fig. 5 and Fig 7: ‘line-to-ground voltage’ -> line-to-ground voltages.

Author Response

Please see the attached response to the reviewer and the tracked changes.

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

Title: Arc Quality Index based on Three-Phase Cassie-Mayr Electric Arc Model of Electric Arc Furnace

Abstract:  What is arc quality index (AQI)?   

Introduction:  ‘This research demonstrates the importance of understanding arc dynamics in EAFs’:  Please give details, not only arc length.       

Materials and Methods:    Section 2.1 is not needed. 

Results:  “It can be seen from the Figure 3 that the arc length exhibits greater variability during the initial melting stage than in the later refining stage.”:  Please explain.  What are the effects on the average arc length (Figure 3)?  Please expand on the link of the scatter in the arc length and the fitness function.  Please elaborate on the reasons for less discrepancy of the the measured and predicted line-to-ground voltages and line currents during refining than melting.  “A significant dip in AQI around 350s in the first and second lines, which is not reflected in the third line, shows the ability of the index to distinguish between different lines.”:  Is it the only outcome?   

Discussion:  ‘the optimization process highlights that these omissions are … through the introduced AQI.’:  Please enhance. 

Conclusions:  ‘..AQI is primarily intended to a decision-making aid for EAF operators.’:  Can be better.   

Author Response

Please see the attached response to the reviewer and the tracked changes.

Author Response File: Author Response.pdf