Round 1

Reviewer 1 Report

The paper is well written and interesting to read.

·        -Please refer eqs that are not yours.

·        -Minor grammar and syntax issues need correction

·        -more simulation results and formal comparison of results are needed

Minor editing of English language required

Author Response

Response to Reviewer 1 Comments Comments and Suggestions for Authors First of all, we thank the reviewer for taking the time to assess our manuscript The paper is well written and interesting to read. · -Please refer eqs that are not yours. Thank you very much for your valuable comments and suggestions. According to your comments, the equations that are not ours will be referenced · -Minor grammar and syntax issues need correction Thank you very much for your valuable comments and suggestions on our work. According to your comments, we have carefully revised our manuscript. · -more simulation results and formal comparison of results are needed Thank you very much for your valuable comments and suggestions. According to reviewer comments, more simulation results and formal comparison of results will be added. The details are shown as follow: Figure 19. Power factor using AST and SMC control Figure 20. Variation of DC link voltage using SMC and AST control The SMC and AST methods are used to control the generator, respectively to demonstrate reference tracking performance and controller resilience. As shown respectively in Figures (8, 9), the mechanical speed deviations follows its references its affected by both turbine design and wind speed, the mechanical power shape is comparable to that of the wind . Figures (10, 12) shows active and reactive power. Figure 10 show the active power, shaped like the wind profile, with negative values since the machine is in generator mode. The reactive power amount shown in Figure 12 is kept at a highly acceptable level in comparison to the immense power of the employed generator. The relatively small reactive power figure indicates the installation has a unity power factor. Oscillations are visible in the shape of the active and reactive power control. Unexpected departures that are rapidly directed toward zero are observed (Figure 12 and 13). These transitions occur when the wind turbine switches between partial and full load regions, also because the disturbance terms and their variations over time are higher than the maximum level at which the controls have been configured. The Figure 11 shows a response time of around 0.025 s using the SMC control and 0.023 s with the AST control which provide a faster response of AST control. The three-phase injected currents ig-abc are illustrated in Figures (14, 16), Under AST as compared to SMC, where some undesirable distortion arises in their morphologies (Figure 15) with SMC method, the injected current waveform acquires a more optimal sinusoidal shape (Figure 17) using AST control which guarantee that the currents injected into the grid are of high quality and that they are in phase with the grid voltages. However, a harmonic analysis of the grid current was carried out to examine the impact of these two controls on the quality of the signal delivered to the grid, as shown in Figure 18. We notice that compared with the result produced by the total harmonic distortion (THD) of the SMC (THD = 3.01%; Figure 16 right), the THD achieved by the suggested AST control (Figure 18 left) was significantly reduced (THD = 1.24%). Figure 19 shows that the power factor is equal to 0.984 with a changing wind profile using the SMC simulation. However, with the AST approach, this rate reaches 0.999. These observed values explain the high quality and performance of the electricity generated. Figures 20 depict the progression of the DC bus voltage in both control, According to these results, the Adaptive approach provides greater V_DC voltage regulation and its stays stable despite wind variations. Compared with the first-order sliding-mode controller [24], which exhibits undesirable chatter, the Adaptive Super Twisting Control offers flawless performance and this problem is mitigated. The evolution of PMSG stator currents [27] demonstrates that the Super Twisting controller can track changes in wind speed better than the SMC. An evaluation table is used to compare the results with some recently published research to validate the AST control. Table 4 compares some of the results, which generally attest to the quality of the proposed control. We appreciate your acceptance of our paper for publication in the electronics Journal. Thank you for your very careful review of our paper, and for the comments, corrections, suggestions that ensued, and in the process, we believe the paper has been significantly improved with your comments. We count ourselves lucky for working with hardworking reviewers like you. We look forward to working with you again in the future.

Author Response File: Author Response.docx

Reviewer 2 Report

The manuscript entitled "Robust Adaptive Super Twisting Algorithm Sliding Mode Control of a Wind System based on the PMSG generator" has been prepared by the authors. It needs revisions. Note the following;

1- Some of the figures need reference such as Figure 1.

2- Writing and grammar need to be improved.

3- It needs to explain the literature and compared the control methods. Refer to the optimization algorithms such as GA, PSO, and TLBO and control techniques such as LQG and FOPID controllers. You can add the following reference to the references:

-Saadatmand M, Gharehpetian GB, Siano P, Alhelou HH. PMU-based FOPID controller of large-scale wind-PV farms for LFO damping in smart grid. IEEE Access. 2021 Jul 2;9:94953-69.

4- Results must be developed.

5- Innovation must be explained clearly.

6- The quality of the figures must be improved.

Dear Editor;

Moderate editing of English language required.

Author Response

Response to Reviewer 2 Comments Comments and Suggestions for Authors The manuscript entitled "Robust Adaptive Super Twisting Algorithm Sliding Mode Control of a Wind System based on the PMSG generator" has been prepared by the authors. It needs revisions. Note the following; First of all, we thank the reviewer for taking the time to assess our manuscript Some of the figures need reference such as Figure 1. Thank you very much for your valuable comments and suggestions. According to your comments, the figures will be referenced Writing and grammar need to be improved. Thank you very much for your valuable comments and suggestions on our work. According to your comments, we have carefully revised and improved the grammar of our manuscript. 3- It needs to explain the literature and compared the control methods. Refer to the optimization algorithms such as GA, PSO, and TLBO and control techniques such as LQG and FOPID controllers. You can add the following reference to the references: -Saadatmand M, Gharehpetian GB, Siano P, Alhelou HH. PMU-based FOPID controller of large-scale wind-PV farms for LFO damping in smart grid. IEEE Access. 2021 Jul 2;9:94953-69. Thank you very much for your valuable comments and suggestions. Those observations are right. According to reviewer comments, the authors have made the necessary changes: Saadatmand, M., Gharehpetian, G. B.(2021) proposed a low-frequency oscillation damping system based on a fractional-order proportional-derivative controller for an (eolien- photovoltaic) park connected to a synchronous generators. Finally, the suggested method's performance is assessed under various operating situations of a reference intelligent system. Results must be developed. Thank you very much for your valuable comments and suggestions on our work. According to your comments, we have carefully added the required information. Thank you for your kind help. The Details are showen as follow: Figure 19. Power factor using AST and SMC control Figure 20. Variation of DC link voltage using SMC and AST control The SMC and AST methods are used to control the generator, respectively to demonstrate reference tracking performance and controller resilience. As shown respectively in Figures (8, 9), the mechanical speed deviations follows its references its affected by both turbine design and wind speed, the mechanical power shape is comparable to that of the wind . Figures (10, 12) shows active and reactive power. Figure 10 show the active power, shaped like the wind profile, with negative values since the machine is in generator mode. The reactive power amount shown in Figure 12 is kept at a highly acceptable level in comparison to the immense power of the employed generator. The relatively small reactive power figure indicates the installation has a unity power factor. Oscillations are visible in the shape of the active and reactive power control. Unexpected departures that are rapidly directed toward zero are observed (Figure 12 and 13). These transitions occur when the wind turbine switches between partial and full load regions, also because the disturbance terms and their variations over time are higher than the maximum level at which the controls have been configured. The Figure 11 shows a response time of around 0.025 s using the SMC control and 0.023 s with the AST control which provide a faster response of AST control. The three-phase injected currents ig-abc are illustrated in Figures (14, 16), Under AST as compared to SMC, where some undesirable distortion arises in their morphologies (Figure 15) with SMC method, the injected current waveform acquires a more optimal sinusoidal shape (Figure 17) using AST control which guarantee that the currents injected into the grid are of high quality and that they are in phase with the grid voltages. However, a harmonic analysis of the grid current was carried out to examine the impact of these two controls on the quality of the signal delivered to the grid, as shown in Figure 18. We notice that compared with the result produced by the total harmonic distortion (THD) of the SMC (THD = 3.01%; Figure 16 right), the THD achieved by the suggested AST control (Figure 18 left) was significantly reduced (THD = 1.24%). Figure 19 shows that the power factor is equal to 0.984 with a changing wind profile using the SMC simulation. However, with the AST approach, this rate reaches 0.999. These observed values explain the high quality and performance of the electricity generated. Figures 20 depict the progression of the DC bus voltage in both control, According to these results, the Adaptive approach provides greater V_DC voltage regulation and its stays stable despite wind variations. Compared with the first-order sliding-mode controller [24], which exhibits undesirable chatter, the Adaptive Super Twisting Control offers flawless performance and this problem is mitigated. The evolution of PMSG stator currents [27] demonstrates that the Super Twisting controller can track changes in wind speed better than the SMC. An evaluation table is used to compare the results with some recently published research to validate the AST control. Table 4 compares some of the results, which generally attest to the quality of the proposed control. 5- Innovation must be explained clearly. Thank you for your valuable comments and suggestions. Based on the reviewers' comments, we have clearly explained the innovation we have introduced in this article. The details are presented as follows: The main result of this study is the development of a robust continuous control approach based on sliding mode control with a super-twist operation to reduce the impact of chattering effect on the control variable, with the aim of guaranteeing and increasing the stability and robustness of our system. The approach will then be called : Robust Adaptive Super Twisting Algorithm Sliding Mode Control (AST). The originality of this work resides in the fact it introduces an innovative control topology that differs from most PMSG wind turbine systems based on sliding mode control. In the face of outside disturbances, the controller can maintain constant transient performance, minimize the load resulting from electrical power generation and improve the quality of the electrical power supplied. 6- The quality of the figures must be improved. Thank you very much for your valuable comments and suggestions. According to your comments, the quality of the figures will be improved We appreciate your acceptance of our paper for publication in the electronics Journal. Thank you for your very careful review of our paper, and for the comments, corrections, suggestions that ensued, and in the process, we believe the paper has been significantly improved with your comments. We count ourselves lucky for working with hardworking reviewers like you. We look forward to working with you again in the future.

Author Response File: Author Response.pdf

Reviewer 3 Report

The article addresses the Adaptive Super Twisting algorithm (AST) to control the Permanent Magnet Synchronous Generator (PMSG) wind power conversion system. The following comments need to be addressed by the authors 

1. Elaborate discussion of ref 13, 43, and 45 is needed.
2. Discuss the estimation of system parameters, such as the inertia and damping coefficients.
3. Discuss the methods applied in the proposed to reduce the mechanical stress on the generator while Controlling the chattering effect.
4. Discuss tuning the AST algorithm's control gains for optimal performance.
5. There is no discussion of Figure 3, Figure 5
6. Two figures have the same number – check Figure 4 (Figure 4. PMSG d-q model and Overview of SMC enhancement methods.)
7. Many typo errors are there (for example, line 20- provide space between toevaluate)

Minor editing of the English language required

Author Response

Response to Reviewer 3 Comments

 

The article addresses the Adaptive Super Twisting algorithm (AST) to control the Permanent Magnet Synchronous Generator (PMSG) wind power conversion system. The following comments need to be addressed by the authors 

First of all, we thank the reviewer for taking the time to assess our manuscript

1. Elaborate discussion of ref 13, 43, and 45 is needed.

 

Thank you very much for your valuable comments and suggestions. According to reviewer comments, a more detailed discussion of refs. 13, 43 and 45 will be added.

 

 

1. Discuss the estimation of system parameters, such as the inertia and damping coefficients.

 

Thank you very much for your valuable comments and suggestions on our work. According to your comments, we have carefully added the required information about the estimation of system parameters. Thank you for your kind help.

The robustness part, the adaptive model, i.e. the parametric variation of the machine, which was the subject of another paper in the classic sliding mode part. For this work, we focused on just the performance improvement part, and will add the super twisting part in future work.

 

 

 

 

1. Discuss the methods applied in the proposed to reduce the mechanical stress on the generator while Controlling the chattering effect.

 

Thank you very much for your valuable comments and suggestions on our work. According to your comments, we have carefully added the required information. Thank you for your kind help. The Details are shown as follow:

 

The main result of this study is the development of a robust continuous control approach based on sliding mode control with a super-twist operation to reduce the impact of chattering effect on the control variable, with the aim of guaranteeing and increasing the stability and robustness of our system. The approach will then be called : Robust Adaptive Super Twisting Algorithm Sliding Mode Control (AST).

The originality of this work resides in the fact it introduces an innovative control topology that differs from most PMSG wind turbine systems based on sliding mode control. In the face of outside disturbances, the controller can maintain constant transient performance, minimize the load resulting from electrical power generation and improve the quality of the electrical power supplied.

 

 

1. Discuss tuning the AST algorithm's control gains for optimal performance.

 

Thank you very much for your valuable comments and suggestions on our work. According to your comments, we have carefully added the required information about the tuning the AST algorithm's control gains for optimal performance. Thank you for your kind help. The Details are shown as follow:

The values of the variables gains utilized during the tests are shown in Table 3. For the numerical validation  (with i=1,2,3) are selected to account for the requirements suggested in equations (44,45,46) and to ensure at all times, each  is proposed to be equivalent to 1. The Adaptive super-twisting algorithm thus ensures the continuity of  that converges to zero in finite time. Furthermore, each will be compensated for all t 0 . Some ideas from [50] are used for this stability analysis.

 

 

**********************************************************************

 

 

 

 

1. There is no discussion of Figure 3, Figure 5

 

Thank you very much for your valuable comments and suggestions on our work. According to your comments, we have carefully added the required information. Thank you for your kind help. The Details are shown as follow:

 

The power coefficient Cp or the aerodynamic efficiency of the wind turbine can be described as [6-7-9-12-14]:

 

                  (4)

 

The Cp is as shown in Figure 3 has a theoretical maximum value of 0.59 known as the Betz limit, it depends on the pitch angle (β) and the tip speed ratio known as the Tip Speed Ratio (TSR) indicated by (λ) [44] [51]:

It is a continuous regulator that ensures all of the first-order SMC control qualities for the system with matching limited uncertainties and disturbances. The super-twisting algorithm's phase plane trajectory is representing in Figure 6.

 

Figure 6. Convergence of the twisting algorithm in terms of time

 

 

 

 

1. Two figures have the same number – check Figure 4 (Figure 4. PMSG d-q model and Overview of SMC enhancement methods.)

Thank you very much for your valuable comments and suggestions. Those observations are right. According to reviewer comments, the authors have made the necessary changes

 

 

 

1. Many typo errors are there (for example, line 20- provide space between toevaluate)

Thank you very much for your valuable comments and suggestions on our work. According to your comments, we have carefully revised our manuscript.

 

We appreciate your acceptance of our paper for publication in the electronics Journal. Thank you for your very careful review of our paper, and for the comments, corrections, suggestions that ensued, and in the process, we believe the paper has been significantly improved with your comments. We count ourselves lucky for working with hardworking reviewers like you. We look forward to working with you again in the future.

 

Author Response File: Author Response.docx

Reviewer 4 Report

The authors present a sliding mode control for a wind turbine integrated with PMSG.  Thanks to the authors, although the topic is of practical importance, the paper has many writing and technical issues.

serious issues:

- For example, the paper is not well-written, the sketchy writing appears  from the abstract that hasn't given an insight of the scientific merit of the paper.

- Then the introduction that is not enough for motivation of the readership. 

- The literature review is not well-written, from the introductory sentence and then mixed tenses of simple past and present are used to describe the work. The writing is wrong even for doubling author orientation, such as (Jian Chen et al. (2019) [27] The authors compare...)

-  The contribution of the paper is not clear enough and there are many papers that deal with SMC of wind-PMSG. The section name is even wrong (Contribution and related work) while it should be only (The paper Contribution).

- section 6.1 should be a part of the literature review where in the paper appears within section dealing with control synthesis. 

- The controller hasn't given significant improvement and even not notable as that in figure. 10. What is the beneficial rule of SMC? is the plant controlled by SMC? what are the controlled variables? Then, the discussion of the results must be rewritten. 

- The x=zoomed figure15 is not matched with that selected in figure 14. The same issue appears in figures 17 and 16. 

Then, there are some minor points, but the above are the most important for the paper to reach the standard. 

minor points

- Figure.4 is repeated in numbering and not cited in the text. However, this could be a minor point.

- unify the font size in the abstract. 

- avoid using pronoun "we" and use passive voice preferably with present perfect tense. 

- and other points. 

The English writing  is very poor. 

Author Response

Response to Reviewer 4 Comments

 

The authors present a sliding mode control for a wind turbine integrated with PMSG.  Thanks to the authors, although the topic is of practical importance, the paper has many writing and technical issues.

First of all, we thank the reviewer for taking the time to assess our manuscript

serious issues:

- For example, the paper is not well-written, the sketchy writing appears  from the abstract that hasn't given an insight of the scientific merit of the paper.

Thank you very much for your valuable comments and suggestions on our work. According to your comments, we have carefully revised our manuscript.

Abstract: In the field of optimizing wind system control approaches and enhancing the quality of electricity generated on the grid, this research makes a fresh addition.

The Sliding Mode Control (SMC) technique produces some fairly intriguing outcomes, but it has a severe flaw in the oscillations (Phenomenon of reluctance: chattering). that diminish the system's efficiency.

In this paper, An AST (Adaptive Super Twisting) approach is proposed to control the wind energy conversion system of the permanent magnet synchronous generator (PMSG), which is connected to the electrical system via two converters (grid-side and machine-side) and a capacitor as a DC link between them, this research seeks to regulate the generator and grid-side converter to monitor the wind rate reference given by the MPPT technique, in order to eliminate the occurrence of the chattering phenomenon.

With the help of this approach, precision and stability flaws will be resolved, and the wind system will perform significantly better in terms of productivity.

To evaluate the performance of each control in terms of reference tracking, response time, stability, and the quality of the signal sent to the network under different wind conditions, a detailed description of the individual controls is given, preceded by a simulation in the Matlab/Simulink environment. The simulation study validated the control method and demonstrated that the AST control based on the Lyapunov stability theory provides excellent THD and Power factor results. This work is completed by a comparative analysis of the other commands to identify the effect on the PMSG wind energy conversion system.

 

- Then the introduction that is not enough for motivation of the readership. 

Thank you very much for your valuable comments and suggestions on our work. This observation is right and according to your comments, we have revised  and improved our introduction.

WECSs are extremely nonlinear systems with a significant quantity of disturbances and uncertainty, according to control literature [28]. As a result, current WECSs necessitate high-performance control approaches such as: backstepping control [29], fractional-order proportional-derivative control [53], predictive control [39]…

In furtherance of the control methods outlined previously mentioned, sliding mode control (SMC) is a prominent approach for sophisticated WECS control. SMC is a popular nonlinear resilient method that, in comparison to other sophisticated control systems, has a comparatively straightforward creation and execution procedure. The major drawback of this approach is the high-frequency oscillations of the state around the sliding commutator, known as "chattering", This is why, in recent years, most of the SMC study [36-40-43] work using higher-order sliding mode (HOSM) [26] has been focused on strategies for chattering reduction.

The best-known control used by HOSM is the super-twisting method (ST) [44], which is increasing in popularity due to its ease of execution and efficacy.

- The literature review is not well-written, from the introductory sentence and then mixed tenses of simple past and present are used to describe the work. The writing is wrong even for doubling author orientation, such as (Jian Chen et al. (2019) [27] The authors compare...)

Thank you very much for your valuable comments and suggestions on our work. According to your comments, we have carefully revised the literature review.

the details are shown as follow:

1. Literature review

Previous renewable WECS studies on adaptive control:

Many researchers are constantly working on more sophisticated control algorithms that take into account the problems associated with non-linear machine models, in order to produce reliable electrical machine controls that resist the failures of traditional controls. The predictive control, the adaptive Backstepping control, the fuzzy logic control, Sliding Mode Control (SMC), and others are examples of these control methods.

In this short review, certain control algorithms employed in the wind energy conversion system are published:

Wenping Cao et al. (2020) [26] presented a new adaptive model-based approach for estimating rotor position and speed as an observer. The suggested solution is based on model predictive control, which eliminates the requirement for speed and position sensors while simultaneously improving the performance of the model-referenced adaptive control system.

Jian Chen et al. (2019) [27] The authors compare two controls based on a doubly-fed induction generator (DFIG-WT) used to convert wind energy, one focusing on vector control (VC) controllers and the other on a perturbation observer-based multiloop adaptive control (POMAC). POMAC outperforms VC in a variety of scenarios, including changeable wind speed situations, according to the simulation and experiment results. 

Manuel Lara et al. (2021) [28] designed a wind turbine adaptive control structure based on the pitch variable using multi-objective optimization, With the objectives to maintain the generator speed at its nominal value, minimize fluctuations, and maintain the generated power constant.

Saadatmand, M., Gharehpetian, G. B.(2021) [53] proposed a low-frequency oscillation damping system based on a fractional-order proportional-derivative controller for an (eolien- photovoltaic) park connected to a synchronous generators. Finally, the suggested method's performance is assessed under various operating situations of a reference intelligent system.

 

El Mourabit Youness et al. (2019) [29] Improved the performance of the conversion system by studying the Backstepping control experimental validation for a permanent magnet synchronous generator (PMSG) wind turbine using the dSPACE DS1104 control board and the Matlab-Simulink environment in both static and dynamic operating modes.

Behnaz Babaghorbani et al. (2021) [30] propose a nonlinear strategy for predictive control of permanent magnet synchronous generator (PMSG) wind turbine systems based on the Lyapunov model, based on the results, the proposed technique provides stability and performance and covers the DC link voltage during faults.

Tummala S. L. V. Ayyarao (2019) [31] develops a new vector control for a DFIG system that is resistant to external perturbations. For this purpose, the internal current loop is replaced by an adaptive sliding-mode controller. Moreover, to prevent chattering and ensure limited time convergence, the control gains are selected based on a positive semi-definite barrier function.

Kanasottu Anil Naik et al. (2020) [32] constructed and developed a DFIG interval type-2 fuzzy-PI controlled rotor side converter, which was used to estimate the gains of the PI controller when the system operating environment varied. As a result, an adaptive structure has been developed which is vital for regulating the DFIG's rotor-side converter. The proposed technique's performance has been studied for a variety of DFIG operating scenarios, including critical failures, power drops, and wind speed variations.

This brief literature review discusses recent WECS controls that are essentially based on PMSG and DFIG. The objective of this paper is to implement and validate the nonlinear adaptive super-twisting sliding mode control for a high-power PMSG-based WECS. A detailed evaluation will be presented in this article, along with a comparison of the results with other research, to demonstrate this control's usefulness.

 

*********************************************

-  The contribution of the paper is not clear enough and there are many papers that deal with SMC of wind-PMSG. The section name is even wrong (Contribution and related work) while it should be only (The paper Contribution).

Thank you for your valuable comments and suggestions. Based on the reviewers' comments, we have clearly explained the contribution we have introduced in this article.  The details are presented as follows and The section name is changed.

The main result of this study is the development of a robust continuous control approach based on sliding mode control with a super-twist operation to reduce the impact of chattering effect on the control variable, with the aim of guaranteeing and increasing the stability and robustness of our system. The approach will then be called : Robust Adaptive Super Twisting Algorithm Sliding Mode Control (AST).

The originality of this work resides in the fact it introduces an innovative control topology that differs from most PMSG wind turbine systems based on sliding mode control. In the face of outside disturbances, the controller can maintain constant transient performance, minimize the load resulting from electrical power generation and improve the quality of the electrical power supplied.

 

*******************************************************

 

- section 6.1 should be a part of the literature review where in the paper appears within section dealing with control synthesis. 

Thank you very much for your valuable comments and suggestions on our work.

Section 6.1 presents the improved SMC control structures that have been proposed to enhance conventional SMC.

- The controller hasn't given significant improvement and even not notable as that in figure. 10. What is the beneficial rule of SMC? is the plant controlled by SMC? what are the controlled variables? Then, the discussion of the results must be rewritten. 

Thank you very much for your valuable comments and suggestions on our work. According to your comments, we have carefully correged the values of the Figure.10 and revised the discussion of the results:

the details are shown as follow:

This research seeks to regulate the generator and grid-side converter to monitor the wind rate reference given by the MPPT technique using AST control in order to eliminate the occurrence of the chattering phenomenon, and improve the quality of the electrical power supplied.

 

Figure 19.  Power factor using AST and SMC control

Figure 20.  Variation of DC link voltage using SMC and AST control

 

The SMC and AST methods are used to control the generator, respectively to demonstrate reference tracking performance and controller resilience.

As shown respectively in Figures (8, 9), the mechanical speed deviations follows its references its affected by both turbine design and wind speed, the mechanical power shape is comparable to that of the wind .

Figures (10, 12) shows active and reactive power. Figure 10 show the active power, shaped like the wind profile, with negative values since the machine is in generator mode. The reactive power amount shown in Figure 12 is kept at a highly acceptable level in comparison to the immense power of the employed generator. The relatively small reactive power figure indicates the installation has a unity power factor.

Oscillations are visible in the shape of the active and reactive power control. Unexpected departures that are rapidly directed toward zero are observed (Figure 12 and 13). These transitions occur when the wind turbine switches between partial and full load regions, also because the disturbance terms and their variations over time are higher than the maximum level at which the controls have been configured.

 

The Figure 11 shows a response time of around 0.025 s using the SMC control and 0.023 s with the AST control which provide a faster response of AST control.

 

The three-phase injected currents ig-abc are illustrated in Figures (14, 16), Under AST as compared to SMC, where some undesirable distortion arises in their morphologies (Figure 15) with SMC method, the injected current waveform acquires a more optimal sinusoidal shape (Figure 17) using AST control  which guarantee that the currents injected into the grid are of high quality and that they are in phase with the grid voltages.

However, a harmonic analysis of the grid current was carried out to examine the impact of these two controls on the quality of the signal delivered to the grid, as shown in Figure 18. We notice that compared with the result produced by the total harmonic distortion (THD) of the SMC (THD = 3.01%; Figure 16 right), the THD achieved by the suggested AST control (Figure 18 left) was significantly reduced (THD = 1.24%).

Figure 19 shows that the power factor is equal to 0.984 with a changing wind profile using the SMC simulation. However, with the AST approach, this rate reaches 0.999. These observed values explain the high quality and performance of the electricity generated.

Figures 20 depict the progression of the DC bus voltage in both control, According to these results, the Adaptive approach provides greater  voltage regulation and its stays stable despite wind variations.

Compared with the first-order sliding-mode controller [24], which exhibits undesirable chatter, the Adaptive Super Twisting Control offers flawless performance and this problem is mitigated. The evolution of PMSG stator currents [27] demonstrates that the Super Twisting controller can track changes in wind speed better than the SMC.

An evaluation table is used to compare the results with some recently published research to validate the AST control. Table 4 compares some of the results, which generally attest to the quality of the proposed control.

- The x=zoomed figure15 is not matched with that selected in figure 14. The same issue appears in figures 17 and 16.

Thank you very much for your valuable comments and suggestions on our work. This observation is right and according to your comments, the error was rectified.

Figure 14. Injected current Ig-abc using SMC control

Figure 15. Zoom of Injected current ig-abc using SMC control

Figure 16. Injected current Ig-abc using AST control

Figure 17. Zoom of Injected current Ig-abc using AST control

 

Then, there are some minor points, but the above are the most important for the paper to reach the standard. 

minor points

- Figure.4 is repeated in numbering and not cited in the text. However, this could be a minor point.

Thank you very much for your valuable comments and suggestions. According to your comments, the figures will be referenced

 

- unify the font size in the abstract. 

Thank you very much for your valuable comments and suggestions on our work. This observation is right and according to your comments, the size was unified.

- avoid using pronoun "we" and use passive voice preferably with present perfect tense. 

Thank you very much for your valuable comments and suggestions on our work. According to your comments, we have carefully revised our manuscript.

- and other points. 

We appreciate your acceptance of our paper for publication in the electronics Journal. Thank you for your very careful review of our paper, and for the comments, corrections, suggestions that ensued, and in the process, we believe the paper has been significantly improved with your comments. We count ourselves lucky for working with hardworking reviewers like you. We look forward to working with you again in the future.

 

Author Response File: Author Response.docx

Round 2

Reviewer 2 Report

The reviewer's concerns have been addressed. It needs a minor revision. What is reference 53? It seems that it is 52

It is ok.

Author Response

Response to Reviewer 2 Comments

 

The reviewer's concerns have been addressed. It needs a minor revision. What is reference 53? It seems that it is 52

rectified

 

We appreciate your acceptance of our paper for publication in the electronics Journal. Thank you for your very careful review of our paper, and for the comments, corrections, suggestions that ensued, and in the process, we believe the paper has been significantly improved with your comments. We count ourselves lucky for working with hardworking reviewers like you. We look forward to working with you again in the future.

 

 

Reviewer 4 Report

Thanks to the authors for answering to my comments professionally. 

Minor edits are needed.

Author Response

Response to Reviewer 4 Comments

 

Thanks to the authors for answering to my comments professionally. 

We appreciate your acceptance of our paper for publication in the electronics Journal. Thank you for your very careful review of our paper, and for the comments, corrections, suggestions that ensued, and in the process, we believe the paper has been significantly improved with your comments. We count ourselves lucky for working with hardworking reviewers like you. We look forward to working with you again in the future.