Single-Step Response and Determination of Power Components Mean Values of PES Using p-q Method during Transients

Round 1

Reviewer 1 Report (New Reviewer)

Dear author

The authors present single step response and determination of power components mean values of pes using p-q method during transients with low novelty. References and citations are not appropriate, there seems to be much work here, but I am afraid that the paper is very hard to follow. Add literatures on THD limit in non-harmonic supply and linear R-L load, so author can follow latest related references such as, (related to power quality enhancement): dynamic performance evaluation of grid-connected hybrid renewable energy-based power generation for stability and power quality enhancement in smart grid, (related to frequency regulations) an integral tilt derivative control strategy for frequency control in multi microgrid system, intelligent fuzzy TIDF-II controller for load frequency control in hybrid energy system, and enhancement of frequency control for stand-alone multi-microgrids. In page 22, The reference currents ?????(?) and ?????(?) currents for compensating by power active filter (PAF compensator) are calculated using Eq. (28). Before this, they should be back-transformed into ?, ?, ?-phase system. kindly re verify. In 104–105-line, author mentioned the “chapters” change to the “sections”, update the figure 13.b. Keywords: power component mean value, 5-, 3-, and 2- 29 phase connection, power electronic system (PES), need to be update.

Thank you

Author Response

Thanks for your comments.

Author Response File: Author Response.pdf

Reviewer 2 Report (New Reviewer)

This paper explained how to determine the mean value of power components with single step response using the p-q method with the examples of three-, five- and two phases systems. The possible combination of supply and load with linear/non-linear behavior are 4 combinations as shown in Section 3. The manuscript focused on how to calculate the mean values of each power components in steady- and transient states of PES, not the implementation. The comments are as follows.

1) The "generalized theory of the instantaneous reactive power in three-phase circuits", proposed by Akagi et al., and also known as the p-q theory, is a well-known tool to analyze three-phase power system in order to detect problems related to harmonics, reactive power and unbalance. The authors used this method to obtain the instantaneous value and use the moving average- and moving rms methods to determine the power component's mean values. This can be applied with other ways such as digital-filtering, which the authors've already mentioned. The examples of five- and two phases systems are the only unseen example in this manuscript where these 2 systems are rarely used. Thus, this is only the contribution in this manuscript.  

2) The modelling and simulation in Section 3 is very long (page8-33). The 4 possible combinations are explained in details; however, this is not the required contribution. This detailed data are redundant.

3) The discussion about PAF is mentioned in Section 4. The transient behavior of the electrical system are common where PAF will applied both feedback and feedforword control to compensate for the transient response. This discussion section probably show no contribution at all.

Author Response

Thanks for your comments.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report (New Reviewer)

Dear author, In Table 15, THD is 0%, what be the fluctuation in practical scenario. Reference [27] is not appropriate, use some novel literature instead of [27]. Also, follow the references that has been suggested in previous revision, need to be go though again. In 459, 456, and 540  line, heading number is missing. Explain working operation of Figure 13 in detail.

 

Author Response

The answer to your comments are explained in attached document. 

Author Response File: Author Response.pdf

Reviewer 2 Report (New Reviewer)

This revised paper has some modifications such as English correction and total harmonic distortion explanation. However; the contribution of this paper, which as the calculation of average power components by p-q method, is not sufficient. The reviewer would like to ask the authors to rethink about the main contribution such as "the power calculation with other new method" or "Is there any gaps using the moving average- and moving rms methods to determine the average power?". Using the examples of five- and two phases systems are unnecessary. This also applies to 4 possible combinations in the modeling and simulation in Section 3 as well. The reviewer would like to encourage the authors to explore more in order to find the stronger contribution. Implementation with the experiment is strongly recommended.

Author Response

The answers to your comments are explained in an attached document. 

Author Response File: Author Response.pdf

This manuscript is a resubmission of an earlier submission. The following is a list of the peer review reports and author responses from that submission.

Round 1

Reviewer 1 Report

This paper investigates the instantaneous power components, especially the distortion component, under various grid and load conditions. The comparison of simulation results is reasonable and the conclusion is clear. However, the purpose of the study is not quite clear.

There are some problems:

1. Pac,rms in Eqn (18b) should be Qac,rms.

2. The multiplication in Eqn (28a,b) does not make sense because the dimensions of the matrix are not compatible.

Reviewer 2 Report

The authors have tried to discuss about a reference signal extraction method. However, the novelty and contribution of this manuscript is vague. It is written with low-quality presentation. There are main issues that make it to be not acceptable to be published. Some additional comments are:

 

1- The novelty of the paper is not clear. Not mentioned in the abstract, introduction, or even in the conclusion part.

2- "This part I of the paper contains a theoretical base...", How many parts the manuscript contain?

3-  In some parts "5-, 3-, and 2- phases of" and the other part is written "five, three and single two-phase"!!

4- In line 25, "Keywords: el. power in AC network; apparent-, active-, blind-, and...".

5- blind power is not popular in power systems, it should be replaced by reactive power.

6- Avoid lumped references.

7- The motivation part in the introduction is so weak.

8- about 90% of references are old.!!!!

9- There is no related reference to this work!!

10- Line:107-115, the explanation about the structure of the paper is not right.

11- Some of the nomenclatures are mentioned inside the manuscript!! line: 152-156.!!!

12- Figure 4ab?  this is not right. All the figure's names must be revised based on the template.

13- equation 13ab???!!!! (line 216)

14-The quantitative parameters ( lines: 280-295, 312-320 and etc. ( must be mentioned as a table.

15- Inside the conclusion part, it is not good to have a figure!!!

 

 

Reviewer 3 Report

It is hard to say what problem do the authors want to solve? The paper presents some review of selected papers related to reactive (and similar) power theories by classical authors that published them long time ago. The question is still open but is it really an important problem? The authors didn't show any convincing proof that their "approach" solves any real life engineering problem. There are many calculations and examples, all of them extremely basic that doesn't show any significant result. The paper is simply unnecessary, not practical and brings more questions than answers. Therefore I consider it of little value.