Evaluating the Performance of Pulsed and Continuous-Wave Lidar Wind Profilers with a Controlled Motion Experiment

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

Review on the manuscript of “Evaluating the Performance of Pulsed and Continous Wave Lidar Wind Profilers by a Controlled Motion Experiment” by Malekmohammadi et al.

 

General Comments:

Wind measurement is important in assess wind resource, wind farm planning and design. As the development of wind measurement technique, the wind profiling lidars on a floating platform have many advantages. However, an important issue raised in the floating lidar systems is the motion of the platform. In this work, on a series of controlled motion experiments is performed to correct the wind measurement by floating lidar systems (the pulsed WindCube V1 and the continuous-wave ZephIR 300). Using the lidar theory and considering the motion effect on lidar measurement, the authors proposed a motion correction method, which includes both rotational and translation motions. The comparison results showed that the WindCube V1 is more prone to motion-induced errors compared to the ZephIR 300 in the majority of test cases. Moreover, the WindCube V1 showed larger variations before and after motion compensation compared to the ZephIR 300.

 

The manuscript is well written and originated. In my opinion, the manuscript should be accepted after considering the specific comments listed below.

 

Specific Comments:

1.         Title: Continous à Continuous

2.         L148-149: “In the case of the WindCube V1, the third independent LOS velocity vr is missing because the LOS velocities are dependent in pairs”. If this is the fact, the fourth LOS vr should be missing too. Then there are only two equations in (2). The wind vector cannot be solved through Eq. (2). Please clarify the point “the LOS velocities are dependent in pairs”.

3.         L155: “B = Θ ± 180°”: Please clarify the conditions of choosing “+” and “-”.

4.         L226: “TI is and estimation…”à“TI is an estimation…”

5.         Figure 9: It is better to add a new panel to show the errors of wind speeds measured by motion (without compensation) and reference lidars and the errors of wind speeds measured by motion (with compensation) and reference lidars. Such that the improvements can be illustrated more directly.

6.         Figure 10: It is better to show a linear fitting line to highlight the improvement of motion correction.

7.         Section 5.4: The wind speeds measured motion and reference lidars are compared here. It is better to provide comparisons of wind directions measured motion and reference lidars since a wind field is determined by both wind speed and direction.

Comments on the Quality of English Language

Review on the manuscript of “Evaluating the Performance of Pulsed and Continous Wave Lidar Wind Profilers by a Controlled Motion Experiment” by Malekmohammadi et al.

 

General Comments:

Wind measurement is important in assess wind resource, wind farm planning and design. As the development of wind measurement technique, the wind profiling lidars on a floating platform have many advantages. However, an important issue raised in the floating lidar systems is the motion of the platform. In this work, on a series of controlled motion experiments is performed to correct the wind measurement by floating lidar systems (the pulsed WindCube V1 and the continuous-wave ZephIR 300). Using the lidar theory and considering the motion effect on lidar measurement, the authors proposed a motion correction method, which includes both rotational and translation motions. The comparison results showed that the WindCube V1 is more prone to motion-induced errors compared to the ZephIR 300 in the majority of test cases. Moreover, the WindCube V1 showed larger variations before and after motion compensation compared to the ZephIR 300.

 

The manuscript is well written and originated. In my opinion, the manuscript should be accepted after considering the specific comments listed below.

 

Specific Comments:

1.         Title: Continous à Continuous

2.         L148-149: “In the case of the WindCube V1, the third independent LOS velocity vr is missing because the LOS velocities are dependent in pairs”. If this is the fact, the fourth LOS vr should be missing too. Then there are only two equations in (2). The wind vector cannot be solved through Eq. (2). Please clarify the point “the LOS velocities are dependent in pairs”.

3.         L155: “B = Θ ± 180°”: Please clarify the conditions of choosing “+” and “-”.

4.         L226: “TI is and estimation…”à“TI is an estimation…”

5.         Figure 9: It is better to add a new panel to show the errors of wind speeds measured by motion (without compensation) and reference lidars and the errors of wind speeds measured by motion (with compensation) and reference lidars. Such that the improvements can be illustrated more directly.

6.         Figure 10: It is better to show a linear fitting line to highlight the improvement of motion correction.

7.         Section 5.4: The wind speeds measured motion and reference lidars are compared here. It is better to provide comparisons of wind directions measured motion and reference lidars since a wind field is determined by both wind speed and direction.

Author Response

Please see the attachment. 

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

The wind lidar on dynamic platform is widely used. How to correct the motion-induced errors is critical question. The authors proposed and evaluated motion correction method in reducing the motion-induced errors for wind profiling lidars on a floating platform. The results showed that the lidars have very good agreement in their mean wind speed measurement when there is no motion. The research is of great significance. After minor revisions, the paper can be considered for acceptance.

The specific opinions are as follows:

1.   The experimental data used in the author's paper is from 2011, which is too early and the experimental conditions and equipment may have changed. It is recommended to use recent experimental data for analysis, which has more guiding significance for error correction.

2.     What is the basis for selecting the number of tests?

3.   In the actual detection process of wind lidar, the motion of the platform is comprehensive, not a single motion. How to correct the errors generated by the comprehensive motion? What is the guiding significance of the analysis in this article?

Comments for author File: Comments.pdf

Author Response

Please see the attachment. 

Author Response File: Author Response.pdf