A Design Review for Biomedical Wireless Power Transfer Systems with a Three-Coil Inductive Link through a Case Study for NICU Applications

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

This work provides a comprehensive review of the fundamentals of inductive wireless power transfer systems, a topic of significant importance and potential. However, I believe the manuscript could benefit from further refinement to enhance its overall quality. Based on the points outlined below, I recommend revising the manuscript before it is considered for publication.

1. Regarding equation (1) on page 6, please specify the type of coil to which this equation is applied. Inductive wireless power transfer systems use various coil types, such as circular or rectangular spiral coils, and helical coils, among others. Clarifying this will improve the manuscript’s accuracy and clarity.
2. On lines 380 to 385 on page 12, could the authors provide more details on how the coupling coefficient k12 is determined to be 0.02 and how the coupling coefficient k23 is adjusted within the range of 0.12 to 0.18? It is important to note that the coupling coefficient is influenced not only by the separation distance between coils but also by the coil diameter.
3. In lines 441 to 442 on page 13, the authors state that the Tx L1 has been optimized to achieve a higher quality factor of 173, which is significantly greater than L2 as shown in Figure 12. Could the authors explain the configuration of the optimized L1 and why the same configuration was not applied to L2?
4. Do the authors have specific considerations for designing L1 with a hexagonal configuration, while L2 and L3 are designed with square configurations?
5. The separation between the resonator and Rx is reported as 0.5 cm and 1 cm, which is relatively close. Have the authors considered how this close distance might shift the resonance frequency of the resonator? Such a frequency detuning could impact the coupling coefficient between the Tx and the resonator.

Author Response

Please see the attachment. 

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

Dear Authors,

As I know, this paper is a review paper for biomedical wireless power transfer (WPT) systems. But the structure of this paper is somewhat strange.

For the review of the biomedical WPT systems, there seems to be a lack of in-depth reviews for the biomedical systems and applications. It just seems like a typical power amplifier review paper, which we are familiar with.

In addition, a case study is included in this review paper. It also seems a bit odd.

Please try rewriting the revision by adding more in-depth review content for biomedical WPT systems and applications.

Thank you for all your effort.

Author Response

Please see the attachment. 

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

1. Since the authors provide a review of WPT systems in general, apart from their contributions, it would be nice if they gave a short record reference on the contribution of metamaterials and their efficiency compared to typical coils.

2. Please provide some additional evidence (CPU time, RAM) required for the simulations of the paper.

3. Have the authors considered any alternative ways of placing the coils in order to increase efficiency?

4. Moreover, some means for the improvement of the coupling coefficient could be discussed and provided.

5. The motives for developing the 3-coil study should be more clearly indicated.

Comments on the Quality of English Language

The language is satisfactory without any significant errors.

Author Response

Please see the attachment. 

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

Comments and Suggestions for Authors

The revised manuscript is well improved with its feedback and update.

I think that it's ready to be published with its minor update, for example, including 'Abbreviations' part at the end of 'Conclusions' part since this manuscript uses a lot of abbreviations.

Thank you for all your effort.

Author Response

Comment:

The revised manuscript is well improved with its feedback and update.

I think that it's ready to be published with its minor update, for example, including the 'Abbreviations' part at the end of 'Conclusions' part since this manuscript uses a lot of abbreviations.

 

Response:

Thank you for your comment. We added the following abbreviations after the "Conclusions" section. 

Abbreviations: Wireless Power Transfer (WPT); Internet of Things (IoT); Electric Vehicles (EV); Electromagnetic (EM); Industrial, Scientific, and Medical (ISM); Radio Frequency (RF); Neonatal Intensive Care Unit (NICU); Power Amplifier (PA); Power Transfer Efficiency (PTE); Metamaterials (MTMs); Specific Absorption Rate (SAR); Power Management Integrated Circuit (PMIC); Bipolar Junction Transistor (BJT); Metal-Oxide-Semiconductor Field-Effect Transistor (MOSFET); Zero-Voltage Switching (ZVS); Dynamic Dead-Time Control (DDTC); Dead-Time (DT); Discontinuous Conduction Mode (DCM); Electromotive Force (EMF); Printed Spiral Coils (PSC); Equivalent Series Resistance (ESR); Additive Manufacturing Electronic (AME); Power Delivered to Load (PDL); Anteroposterior (AP); Vector Network Analyzer (VNA); Surface Mount Device (SMD).

Reviewer 3 Report

Comments and Suggestions for Authors

In this revised version, the authors have successfully conducted the majority of my comments. Therefore, I think that the paper can be accepted for publication.

Comments on the Quality of English Language

No particular comments.