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Discussion Starter · #121 ·
Here's the KiCAD rendering of the built instrument panel dev board to complete the set of four controller dev boards.
The images posted here do not refelect the boards as they have been built.
Some tracks are wider, parts have been moved, copper areas have been added etc.

But now the SiC HV laminated busbar design can be designed and built.
Always six TO247-4L mosfets. Package current limit is 110Arms. This means that 100kW+ can be achieved at 800V DC bus. dev_board_instrumentpanel.png
 

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Discussion Starter · #122 ·
ICE EMULATION module

Yep, that's right. The easiest and most efficient way to convert an ICE vehicle with a lot of modern electronics (read: micro-controllers) is emulating the ICE.
I certainly don't want to be limited to converting 30 to 50 year old "breaker point" cars.

My conversion kit has 4 micro-controllers. One of them runs the emulation software. For petrol engines. Turbochargers are supported. 🙂

The COVID-19 lock-down measures provide the ideal circumstances for software development.
A major part of the emulation software is ready: the airflow / manifold pressure calculations.
 

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Yup - that's what the world wants in an EV...built in hesitation when the accelerator gets pressed, gradual increase in torque until it hits 4,000rpm, unbalanced missing phase power ("misfire"), stalling now and then, randomly refusing to start in cold weather, making random noises, dumping massive power into the stator to make the coolant overheat & vent the radiator cap, and opening a servo valve proportional to distance driven to drip gearbox oil on the floor 😂
 

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Discussion Starter · #124 ·
Yup - that's what the world wants in an EV...built in hesitation when the accelerator gets pressed, gradual increase in torque until it hits 4,000rpm, unbalanced missing phase power ("misfire"), stalling now and then, randomly refusing to start in cold weather, making random noises, dumping massive power into the stator to make the coolant overheat & vent the radiator cap, and opening a servo valve proportional to distance driven to drip gearbox oil on the floor 😂
Too bad you didn't get it this time.... but virtually you're partially right. The virtual ICE doesn't have leaky valves, torque is almost instant and there's no turbo lag.
Virtually misfires can happen but they do not affect performance and they do not throw a Check Engine.
Emulation is solely done to keep the existing controllers doing all but control the engine.
 

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Discussion Starter · #125 ·
Since 2007 I have built several experimental circuits to try out control methods and DIY designs. For instance LLC circuits.

Here's a screenshot of the FINAL LTSPICE simulation of the multi branch LLC, current mode, primary side uC controlled isolated gate power supplies for the SiC 800V inverter hardware.

This circuit will be built soon. Widely available common mode filter chokes can be used as transformers.
LLC_iso_ps_gatedrivers.png
 

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Discussion Starter · #127 ·
And the walk in the park has begun ... Here's an image of one of the many, many steps.
Looks like the UnitedSiC models steer the designer towards -5/12.9 V gate drive.
LTSPICE convergence issues with lower values.

Industry trend is still: go with 800V and SiC fets.

The new Hyundai IONIQ5 is 800V.
Great styling, excellent value for money. Beats Tesla III/Y IMHO.
one_of_many_runs.png
 

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Discussion Starter · #130 ·
@remy_martian: KiCAD Squarematic :) of the 350 to 800V cascode 100kW+ inverter.

Yep, this means that the design is done. It is the result of seven years sharing DIY approaches and experimental circuits.
Some results: LLC power supply in current mode with post shunt regulation, cascode SiC for hard switching.
inverter.png

AGAIN: this schematic is only indicative of the final result. Details may change and can be found elsewhere online soon.
Example: Two IXYS604 devices in stead of one to prevent shoot through currents in the mosfet LLC out stages of the LLC.
Compliance LT1720 fast comparator will be replaced with automotive grade TS3011IYDT in the final result.
 

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Discussion Starter · #132 ·
Sure. Making the world a little better is a serious matter.

Kelvin and LV/HV signal isolation: automotive grade ADuM 241/242E0. CANBUS, gate signals, fault....
Mosfets in parallel: timing is critical. I'm using a FPGA for it.
For now (development phase): LATTICE ICE40 HX8K on a Sparkfun Alchitry Cu. Reason: there's an open source toolkit for it.
Later on the verilog design will be ported to an automotive grade FPGA.
With a FPGA the ATmega32M1 has enough throughput for the remaining tasks: CANBUS, SPI link to FPGA, PWM.
Selected mosfet driver: Texas Instruments UCC27519AQDBVRQ1, Fast, automotive grade, inexpensive, both TTL and CMOS level inputs.

ALL PARTS ARE AUTOMOTIVE GRADE in the final design. DISCRETES, FOR EXAMPLE: Nexperia PMV37ENEA trench mosfet.

This project is NOT cheap, NOT inexpensive and @100kW+ is certainly NOT a walk in the park.
1. But a 400V, 40kW air cooled inverter IS. 40kW, 400V doesn't need mosfets in parallel.
2. The 350 to 800V 100kW+ design does need it. Supports up to 8 mosfets in parallel.
3. 110A is the current limit of the TO247-4 package, but it is NOT achievable in a 800V, 100kW+ system. Thermal limits.
4. 30 (air cooled) to 40Arms (liquid) is the limit per mosfet @800V.
5. The existing gate driver circuits for IGBT and SI/SiC mosfets won't work for 800V high amp devices in parallel @ 100kW+.

Ultimately, the inexpensive all hardware controller project is also a FPGA project. Just for the record.
 

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Discussion Starter · #133 ·
OK, here's the gate driver circuit for parallel operation at 800V, 100kW+. DON'T USE THIS IN A BUILD UNLESS YOU ARE A TRAINED PROFESSIONAL.
gatedriver_parallel_800V.png
NO REALLY: DON'T.
 

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Discussion Starter · #134 ·
Please keep in mind that this is a project in progress. Turns out the ADuM241E0 is not available as an automotive qualified part.
So here's the next version for KELVIN ISOLATION.

gatedriver_parallel_800V_1.png
:)
 

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Discussion Starter · #135 ·
The pulse transformer has been dropped. No longer needed.
Solved with the aid of LTSPICE and signal rerouting via the FPGA.

So here's version 2. Also: minor change in PS/UVLO. Wiring OOPS.
gatedriver_parallel_800V_V2.png

Please keep in mind that this a SIC project in the development phase.

DO NOT APPLY THE CIRCUITS IN THIS THREAD TO IGBT BUILDS.
NO, REALLY, DON'T.
 

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Discussion Starter · #136 ·
Progress report. Much earlier I introduced SPI in this thread and other projects. SPI is great for implementation in a FPGA.
The ICE40 HX comes with SPI on-chip. Here's the FPGA squarematic with supporting circuits. It is a copy of one of the 80 KiCAD project sheets (squarematics).
DON'T USE THESE CIRCUITS YET!! NO, REALLY, DON'T. In development.
sic_fpga_uc_gatedriver.png
 
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