Hello,
I’m using KiCAD 9.0rc2 to simulate a power inverter.
Application: KiCad Schematic Editor x86_64 on x86_64
Version: 9.0.0-rc2-288-g9083c9e6ab-dirty, release build
Libraries:
wxWidgets 3.2.6
FreeType 2.13.3
HarfBuzz 10.2.0
FontConfig 2.15.0
libcurl/8.11.1 GnuTLS/3.8.8 zlib/1.3.1 brotli/1.1.0 zstd/1.5.6 libidn2/2.3.7 libpsl/0.21.2 libssh2/1.11.1 nghttp2/1.64.0 ngtcp2/1.9.1 nghttp3/1.6.0 librtmp/2.3 OpenLDAP/2.6.9
Platform: Devuan GNU/Linux 6 (excalibur/ceres), 64 bit, Little endian, wxGTK, X11, , x11
OpenGL: AMD, AMD Radeon RX 570 Series (radeonsi, polaris10, LLVM 19.1.4, DRM 3.59, 6.12.9-amd64), 4.6 (Compatibility Profile) Mesa 24.2.8-1
Build Info:
Date: Jan 30 2025 12:09:11
wxWidgets: 3.2.6 (wchar_t,wx containers) GTK+ 3.24
Boost: 1.74.0
OCC: 7.8.1
Curl: 8.11.1
ngspice: 44
Compiler: GCC 14.2.0 with C++ ABI 1019
KICAD_IPC_API=ON
Locale:
Lang: fr_FR
Enc: UTF-8
Num: 1 234,5
Encoded кΩ丈: D0BACEA9E4B888 (sys), D0BACEA9E4B888 (utf8)
My schematic is:
sim_onduleur.pdf (200.0 KB)
Simulation runs as expected if I remove R8 and add R13 from netlist (pure resistive load). Currents in Q1 and Q2 are around 9 A when mosfets are switched on (expected values).
Now, I’m trying to simulate circuit with R8 and without R13. Currents in mosfets are greater than 60 A. In some configurations, currents are greater than 150 A! Thus, Q1 and Q2 should be destroyed as their maximum power are exceeded.
On real circuit, Q1 and Q2 stay cold.
I have tried to add RC snubber on transformer (C6/R17) without success. I suspect an issue with IDH02 model but I’m not sure. My design doesn’t seem to be faulty as it runs as expected. But why does simulation return this result ?
Regards,
JB
PS: netlist and models
sim_onduleur.cir (1.9 KB)
OptiMOS3_250V.lib (93.3 KB)
SCS_G5_1200V_v1_IDH.lib (13.5 KB)
standard_bjt.lib (306.4 KB)
stth1r02.lib (150 Bytes)
transformateur.lib (831 Bytes)