Multiple-Output DC–DC Converters: Applications and Solutions

Round 1

Reviewer 1 Report

This paper has completely sorted out various DC/DC architectures, and explained their advantages and disadvantages, and then talked about the application level of various DC/DCs. The content is very substantial and complete. For beginners, it is a great help, I am sure attentiveness of the authors. There are many websites in the Reference, please make sure to confirm the validity of the links to their websites for easy reference. 

Author Response

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Reviewer 2 Report

The main contribution of the paper is a comprehensive survey of multiple output DC-DC converters. In my opinion paper is interesting and well prepared. A references list consists more than 150 positions, what proves, that the topic has been comprehensive explored by the Authors. However, some significant improvements are required before paper acceptance for publishing.

My following comments are:

1) I suggest to add theoretical currents and voltages waveforms to show converters principles of operation.

2) I suggest to add a tables, where basic features of considered converters are compared eg. number of switches, voltages and currents stress etc. Advantages and disadvantages of compared converters should be also presented in these tables.

3) Authors may also add a description of multi-transformer topologies eg. in a flyback configuration.

4) In paragraph 3.1 and so on, I suggest to indicate and discuss the topologies, which are the most suitable for considered range of applications.

Author Response

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Reviewer 3 Report

The proposed manuscript is a comprehensive review paper concerning the most important multiple output DC-DC converters, providing also three representative practical examples. Nevertheless, several remarks and concerns can be formulated, as follows:

1. At lines 12-13, it should be used either "integrated solutions" or "an integrated solution".
2. At line 14, I suggest replacing “to providing” with “provides”.
3. The phrase “Moreover, the demand for multiple output DC-DC 84 converters with multiple outputs […]” contains twice “multiple output”.
4. Al line 87, the order of the words “[…] Vehicle (HEV) and Hybrid Electric” should be corrected to “[…], and Hybrid Electric Vehicle (HEV).”
5. What do the authors mean by “the most defined”?
6. The significance of the quantities appearing in Figures 1-5 and Tables 1-3 is not disclosed and commented. A nomenclature list (table) would be necessary for that respect. The role of the components is not discussed and how they differently come into play for each topology. The structural differences between the variants are not sufficiently commented from the perspective of their functionality, i.e., what advantages/disadvantages present one topology vs. another one.
7. What does the equal sign with a dot above mean?
8. The references for the formulas contained in Tables 1-3 are not provided.
9. The correct spelling is “Diesel”. Similarly, correct “now-adays” to “nowadays”.

Author Response

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Reviewer 4 Report

Please see my comments below:

1. In line 35, why is LDOs classified with system level applications such as electric vehicles? They are a type of DC-DC converter, and not an application for it. Please change the sentence to reflect this suggestion.
2. For lines 53-55, please address what specific improvements and limitations exist for the si-based technologies.
3. In lines 163-166, for variable frequency constant on time, and variable frequency constant off time, the variation of the operating frequency is the same two reasons: input voltage and load current. Is that intended? What is the reason for both types of control to exhibit the same characteristics for their operating frequency variation with respect to input voltage and load current?
4. For lines 183-187, the readability of the text would improve if you provide the B-H curve you are referring it in those lines.
5. For lines 189- 209, please create a sub-section for each category. For example, the section is Buck-Derived DC-DC Converters, similarly for the others like Resonant Converters, etc..
6. For Fig. 2 and Fig. 3 these are single output topologies, what is the relevance to show and discuss them? Same for Fig. 4 © and (d). Please remove, and edit accordingly.
7. For Fig. 5 (a) and (b) where are the 2^nd outputs in both cases? These figures are again single output, please clarify.
8. In Fig. 7 (a), © please clarify the operation and correctness of the Figure from [68-69, 71].

9.  For Fig.12, it would greatly help to the reader If the topologies you have introduced are also associated/included in the figure to showcase where they can effectively be used in each application.

10. Please describe, and discuss some of the SIMO control issues, and design trade-offs. For example, choice of inductor value, switching frequency, free-wheeling time, output ordering/priority, and efficiency penalties.

Author Response

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Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

I have no further comments. Paper may accepted.