Thermal Stress Reduction of Power MOSFET with Dynamic Gate Voltage Control and Circulation Current Injection in Electric Drive Application

Round 1

Reviewer 1 Report

The paper proposes two methods for reducing the thermal swing of a power MOSFET in electric drive applications. A detailed model of the MOSFET is shown; results are given in simulation an by experimental verification on a case study. 

The paper is well written, the theoretical results are confirmed by the experimental analysis: the proposed method is able to reduce the thermal swing with an increase of the power losses and consequent reduction of the overall efficiency. 

Before publication, in the reviewer's opinion, there are some issues to be discussed: 

a) the method adopted to extract the parameters should be described to justify the accuracy (4th decimal place) of the values shown in table 1. How the accuracy can influence your results? 

b) it is unclear how data-sheet is used for model fitting. Are the points taken by the curves? Is it possible to take into account the device parameter spread?

c) a gate profile is chosen at the end, it encompasses four parameters: the initial amplitude and duration, the final amplitude and its duration. It is unclear how these parameters can be chosen; is it valid only for the MOSFET under investigation?    

minor: 

d) "Rotary machine" should be "rotating machine"

e) line 214 does levitated mean raised?

f) line 219 "loses" should be "losses" 

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

In this paper a model-based dynamic gate voltage control strategy is proposed to reduce the thermal stress by shaping the profile of conduction losses. Gate voltage also affects the losses of the device. Efficiency, that is a key factor today, is consequently affected. The paper is well written, although efficiency is affected using this way for thermal control and increment of the MOSFETs lifetime.

Page 4
91 "While the frequency ω0 of a sinusoidal load current Iload(t) ranges around few tens Hertz, the junction temperature profile follows the shape of power losses, which varies at twice the load frequency [22]", this is so, but I am not sure that it is documented like this in [22].

Author Response

Please see the attachment

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Dear Authors, thanks a lot for responding to my comments. 

It is an interesting paper. 

Author Response

 "Please see the attachment."

Author Response File: Author Response.pdf