Impact of Component Dispersion in DC to DC Low-Power Low-Voltage Power Converter Array

Round 1

Reviewer 1 Report

Review: Impact of Component Dispersion in DC to DC Low Power Low Voltage Power Converter
Array
Interesting and almost exhaustive overview and analysis of the possible problems due to yield issues in
Power Converter Arrays.
Some typos in text:
24: are gaining interest
36: designed,
37: is obtained
39: quantities
42: distribution losses / as for example in the case of
50: before being
51: conditions dedicated
82: and also
89: to rectify?
93: this makes the DAB converter a very
111: is provided in ???
135: it is introduced
137: further analyze
167: and listed
226: expected
Figure 6: please check I guess “a)” is misplaced
246: that the most relevant parameter is
335: always measures
337: this approach, combined
343: points
392: considerations, comments
445: understanding
478: that needs
531: It has been shown
some clarifications:
34-35: please give a better explanation of monolithic vs hybrid solutions
64: do you think this approach can be reasonably extended to closed loop control?
84: CSCs are all the same: so what does it imply concerning balancing techniques introduced in
previous sentence?
87: characteristics of a reference CSC?
168: very sensitive to what?
332: usually in plug sockets also parasitic inductance is significant, have you considered that?
Eq. 2: was this formula numerically verified?
387: As reported in literature… a reference here could be helpful.
465: Concerning self-heating, it seems that the position of CSC (external or middle) is the most
significant parameter, regardless the uneven distribution of power consumption among CSCs, is it true?
Please comment about that
528: of power conversion cells
IMPORTANT: unclear points to be better explained:
56-66: If I correctly understand the paper, there is just one single architecture of the CSC under
discussion, that was produced in 250 pieces, and then 130 out of them was tested in this job. This part
is a little bit misleading, as it seems that you actually have different types of CSCs (“The paper will
describe at first the CSCs that are considered). I would suggest to slightly rephrase this paragraph, for
example: “The paper will describe at first the architecture of the CSC under study and its electrical
characteristics…. For that, three CSC families are identified according to their actual measured
characteristics with respect to nominal values”.
Otherwise, if there are different architectures, please specify better each of them.
Figure 1: I guess ISOS configuration is missing in the caption
Eq. 1: please specify the meaning of α (alpha)
170-180: To better understand the point I suggest a more precise introductory phrase, e.g. “Specifically
it can be seen that with a Vout/Vin ratio higher than… the efficiency becomes significantly sensitive
to… while below this ratio… So three different operating points was considered to cover all operating
regions”
196-197: Not clear what you mean here, please rephrase
Figure 5.a: Is this a normalized graph around unity (1)? If so, please specify, otherwise why average
value of test number one is 1 instead of 13.5/15?
216-219: This point must be clarified: does variable z (1-2-3) refer in any way to the tests N 1-2-3 of
table 3? In other words for example, with CSC B,1 do you mean a sample that in the specific operating
point number 1 lays in the “B quintile”, or do you mean a generic sample that lays in the “B quintile”
regardless the operating point? This leads to another aspect to be discussed: a CSC which lays in the
“A quintile” for test number 1 (far left of blue line in picture 5) will also be in “A quintile” for tests
numer 2-3 (far left of orange and gray line)? Do you observe a correlation in that?

 

Author Response

Dear Reviewer, Thank you for your inbterest ibn our work and thnak you for the numerous comments and remarks that are helpfull in improving our work. PLease find below our feedback.

Some typos in the text:
24: are gaining interest
This error has been corrected directly in the text (line 24)

36: designed,
This error has been corrected directly in the text (line 36)

37: is obtained
This error has been corrected directly in the text (line 41)

39: quantities
This error has been corrected directly in the text (line 44)

42: distribution losses / as for example in the case of
This error has been corrected directly in the text (lines 47-48)

50: before being
This error has been corrected directly in the text (line 55)

51: conditions dedicated
This error has been corrected directly in the text (line 56)

82: and also
This error has been corrected directly in the text (line 94)

89: to rectify?
A complete sentence has been added to fully explain this capacitors aim (lines 101-106)

93: this makes the DAB converter a very
This error has been corrected directly in the text (line 113)

111: is provided in ???
This sentence has been removed.

135: it is introduced
This error has been corrected directly in the text (line 1 (line 154))

137: further analyze
This error has been corrected directly in the text (line 155)

167: and listed
This error has been corrected directly in the text (line 186)

226: expected
This error has been corrected directly in the text (line 262)


Figure 6: please check I guess “a)” is misplaced
This error has been corrected directly in the text (line 266)

246: that the most relevant parameter is
This error has been corrected directly in the text (line 283)

335: always measures
This error has been corrected directly in the text (lines 375-376)

337: this approach, combined
This error has been corrected directly in the text (line 378)

343: points
This error has been corrected directly in the text (line 384)

392: considerations, comments
This error has been corrected directly in the text (line 434)

445: understanding
This error has been corrected directly in the text (line 489)

478: that needs
This error has been corrected directly in the text (line 527)

531: It has been shown
This error has been corrected directly in the text (line 580)

some clarifications:

34-35: please give a better explanation of monolithic vs hybrid solutions
A new sentence has been added to fully explain difference in lines 35-40.

64: do you think this approach can be reasonably extended to closed loop control?
A new sentence has been added to fully explain difference in lines 71-75.

84: CSCs are all the same: so what does it imply concerning balancing techniques introduced in previous sentence?
A new sentence has been added to fully explain difference in lines 71-75.

87: characteristics of a reference CSC?
It is precised in table 1 (line 138)

168: very sensitive to what?
It is precised in the added lines 188-191 and in the next sentence.

332: usually in plug sockets also parasitic inductance is significant, have you considered that?
A new sentence is added in lines 361-365 to explain that.


Eq. 2: was this formula numerically verified?
A new sentence is added in line 419 to explain that.

387: As reported in literature… a reference here could be helpful.
It has been added (line 429 and lines 640-641)

465: Concerning self-heating, it seems that the position of CSC (external or middle) is the most significant parameter, regardless the uneven distribution of power consumption among CSCs, is it true? Please comment about that.
A sentence has been added in lines 509-514

528: of power conversion cells
It has been added in line 577

IMPORTANT: unclear points to be better explained: 56-66: If I correctly understand the paper, there is just one single architecture of the CSC under discussion, that was produced in 250 pieces, and then 130 out of them was tested in this job. This part is a little bit misleading, as it seems that you actually have different types of CSCs (“The paper will describe at first the CSCs that are considered). I would suggest to slightly rephrase this paragraph, for example: “The paper will describe at first the architecture of the CSC under study and its electrical characteristics…. For that, three CSC families are identified according to their actual measured characteristics with respect to nominal values”.
It has been added in lines 61-64

Otherwise, if there are different architectures, please specify better each of them.
It has been added in line 98

Figure 1: I guess ISOS configuration is missing in the caption
It has been corrected in figure 1 legend (line 116)

Eq. 1: please specify the meaning of α (alpha)
It has been explained in lines 110-113

 

170-180: To better understand the point I suggest a more precise introductory phrase, e.g. “Specifically it can be seen that with a Vout/Vin ratio higher than… the efficiency becomes significantly sensitive to… while below this ratio… So three different operating points was considered to cover all operating regions”
It has been added in lines 178-182

196-197: Not clear what you mean here, please rephrase
It has been added in lines 212-217

Figure 5.a: Is this a normalized graph around unity (1)? If so, please specify, otherwise why average value of test number one is 1 instead of 13.5/15?
It has been clarified in figure 5)a) (line 228)
 

216-219: This point must be clarified: does variable z (1-2-3) refer in any way to the tests N 1-2-3 of table 3? In other words for example, with CSC B,1 do you mean a sample that in the specific operating point number 1 lays in the “B quintile”, or do you mean a generic sample that lays in the “B quintile” regardless the operating point? This leads to another aspect to be discussed: a CSC which lays in the “A quintile” for test number 1 (far left of blue line in picture 5) will also be in “A quintile” for tests numer 2-3 (far left of orange and gray line)? Do you observe a correlation in that? This point is not clear in the paper.
An additional explanation has been added in the lines 248-253. There is no link with test 1-2-3 | The quintile are the same whatever the test.

Reviewer 2 Report

For eqn.1, the variables of alpha and f_sw should be defined, a corresponding waveform to alpha might be presented. ISOP, IPOS, and ISOS should be defined by the related diagrams/circuits.

Author Response

Dear reviewer, thank you for your positive feedback. Please find below our answers to your comments.

For eqn.1, the variables of alpha and f_sw should be defined, a corresponding waveform to alpha might be presented. ISOP, IPOS, and ISOS should be defined by the related diagrams/circuits.
These points have been more precisely defined in the text. These changes are placed on the lines 83-84 and 110-114.  

Reviewer 3 Report

The work focuses on the impact of the spread and distribution of the conversion cell characteristics on the characteristics and performances of the Power Converter. It presents several use case scenarios and relevant metrics for an array of power converters. Overall interesting results is being reported on how components can be seleved. The paper will be of interest to the research community.

The paper has got quite a few grammatical errors which authors may want to address.

Author Response

Dear reviewer, thank you for your positive feedback regarding our research work. Please find below our answers to your comments and remarks.

The paper has got quite a few grammatical errors which authors may want to address.
Some corrections are visible on the updated paper. We hope we have seen most of grammatical errors.