An Integrated Digital Signal Feedback Sensor for Fast Transient Measurements of SiC-MOSFET Modules

This article proposes a digital signal feedback sensor design method for silicon carbide (SiC)
mosfet
modules to be used in active gate drivers in the future. This real-time detection method provides high bandwidth, high integrated density, and low latency in transient measurements. In this article, novel solutions are developed to address the shortcomings of the current research. First, the boundary conditions for nonisolated voltage measurement of
${V_{\text{DS}}}$
and
${V_{\text{KS}}}$
in SiC-
mosfet
modules are established. Second, the delay time of each state variable is specified for digital real-time detection. Third, the effect of temperature on parasitic resistance is analyzed during transients and
${I_{D}}$
is calculated in real time using a correction filter algorithm. For verification, a digital signal feedback sensor was applied to a double-pulse circuit. The results show a high integrated density of up to
${1.3\text{kA}/{\text{in}}^{3}}$
and
${\text{6.7}\,\text{kV}/{\text{in}}^{3}}$
while achieving a bandwidth of more than
${\text{20}\,\text{MHz}}$
. The relative error of measuring
${V_{\text{DS}}}$
,
${dV_{\text{DS}}/dt}$
,
${dI_{D}/dt}$
, and
${I_{D}}$
is within
${2\%}$
,
${5\%}$
,
${9\%}$
, and
${6\%}$
. In addition, the fastest transition time of the state variables is only
${\text{13}\,\text{ns}}$
. In summary, this design provides an engineering reference and theoretical basis for the implementation of a digital feedback active gate driver.