What is wrong with my kicad6 kicad_sch file?


I am able to create gerber files, but if i view it with gerber viewer it seems empty.

That’s the schematic. Have you done the PCB layout? You’ll need to design your board before your gerbers contain anything.

thx a lot, after your hint i see the issue now:

Error: Cannot add U1 (no footprint assigned).
Error: Cannot add r10 (no footprint assigned).
Error: Cannot add R5 (no footprint assigned).
Error: Cannot add R3 (no footprint assigned).

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Maybe start with cleaning up the schematic a bit?

I’ve been staring at your schematic from before gkeeth posted. (although not continuously) and I’m still not sure whether to take it seriously or as a joke.

Most likely is it grew organically from a reverse engineering effort.
Also, apart from the missing “no connect flags”, the cathode of D4 is not connected to anything but a wire. I suppose you forgot to add a connector for the FF150R12RT4 module.

Also, it’s a 1500V 150A IGBT module:

Even more reason to clean up your schematic. I would probably air wire it so the high currents do not even go through the PCB, and then only design the PCB for the optocoupler, logic IC and the passives.

With these kind of power levels, stray inductance and capacitive coupling can wreak havoc in your circuit. Even though there are not many parts, designing a proper PCB is not trivial here, and faults have the potential to release lots of (expensive) fireworks.

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Thank you for the valuable information! In fact, I will now connect the IGBT module via a free wire jumper to test the PV inverter.

It seems you are a professional… Do you see a chance to clock down that board to 50 Hz?

I had a short look at that site but did not really understand your question and skipped it.

A bit later I noticed the headline of the IR2153 as being a “Self-Oscillating Half-Bride Driver”, and the oscillation frequency is just set with an external RC combination. It’s got a chart that goes down to 60Hz with a 1Meg resistor and 10nF capacitor, so with a slightly bigger capacitor it should work at 50Hz. You can probably also clock it with an external signal (maybe derived from you local 50Hz mains?)

You may have to increase the bootstrap capacitor for the high side fet at such low frequencies. But start by having a look at the IR2153 datasheet to see how it works.

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I think i found the best full bridge driver for 50Hz now:
50Hz RC = **5.30785562633 KΩ + 600nF

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