Can't Kill A Toyota Inverter

[clanger9]

Amazing. With zero dead time, how on earth did the IGBTs survive?

[MattsAwesomeStuff]

I'm glad you're figuring this stuff out, it's the kind of thing that someone just bungling along and hoping for the best would definitely also fail at, and then not know how to fix. I could've looked right at that waveform and not known what to do about it.

Problem could've been hardware, software, fuckin' tupperware for all I know about troubleshooting it.

[mdrobnak]

I can hear arber now.

[celeron55]

Should we ask how much deadtime did the wise man Mr. Hübner set by default on his new Prius gen2 offering?

[SciroccoEV]

Should we ask how much deadtime did the wise man Mr. Hübner set by default on his new Prius gen2 offering?

ZERO of course!

[arber333]

You are learning grasshopper!
Adaptation, improvization... but your weakness is not your technique.

EDIT: By now i would think every OEM inverter runs on 3us deadtime, at least.
Only we DIY are banging our heads at 1.2us ideal.

[Isaac96]

Can we measure OEM inverter deadtimes somehow? Maybe a Lexus transmission because those are being run by the original brain board still. I guess it's possible to measure deadtime of any inverter which is controlled over CAN. I wonder what Tesla is using for their parallel IGBT setup.

[joromy]

Can we measure OEM inverter deadtimes somehow? Maybe a Lexus transmission because those are being run by the original brain board still. I guess it's possible to measure deadtime of any inverter which is controlled over CAN. I wonder what Tesla is using for their parallel IGBT setup.

If you have a scope you can do it the analog way.
Don't think it will be possible to find any DT on the CAN, if it was that you meant?

This is from Siemens/Ford original inverter, about 1uS (880nS):

[johu]

Should we ask how much deadtime did the wise man Mr. Hübner set by default on his new Prius gen2 offering?

ZERO of course!

Right sir, ain't no deadtime if you can't control low and high side separately

I also found that OEM power stages need heaps of deadtime. Never bothered to calculate the us but the coded value is 78 for the Leaf stage. On my home brew power stage there is absolutely no current draw with deadtime 63.

[Dilbert]

I'm very impressed with the toyota de-sat protection/detection, that it was able to handle the zero dead time and protect the devices, very impressive. It goes to show how robust these inverters are.

[johnspark]

I think it is worth pointing out that all Toyota HV cables are shielded. That means they are turned into RLC waveguides. By having a shield around the cable the capacitance / unit length is controlled by Toyota, and not by placement of cables. No shield means a whole lot of ringing, reflections, and creation of EMI for other things. Shield means overall slower rise times and smaller spikes.

[Jack Bauer]

Update time. Got a CT200h inverter which is exactly the same as a Prius Gen3 inverter on the outside but actually uses the same logic board as the Auris/Yaris inverter. So fitted an Auris/Yaris board, made some simple code to buck the 360v down to 220v to run the dcdc converter, added some DEADTIME! to the settings, installed in the car annnddd....no bangs so far.

Observations : used the old connection points to see if it would explode. So far not. Will update on this.

I have the engine temp gauge in the E39 mapped over can to the heatsink temp in the inverter, now when revving the motor in neutral with the old setup it would jump up very fast. Now it hardly moves at all. I guess thats what 12 transistors in shoot through will do to you....

[rstevens81]

Might be a silly question what advantage does the old connection point have?
is it an ease of access thing or are the cables in the landyacht only fit in the old place?

[johnspark]

Do you know if the buck/boost has the unkillable Toyota spirit? If I inadvertently enabled high side and low side while playing with the atmega, would it ignore me and laugh or self destruct?

From experience with the GS unit, which I imagine is similar, the IPM should prevent this occurring. However I've had a GS converter self destruct with signs of a HV - Ground fault, after several hours (probably 20 or so hours) of testing. So I'm not sure how robust that protection is.

Unless I completely mis-understood the documented features of a Prius Inverter/Converter.... The boost feature both increases MG1/2 output during "regen" to get volts high enough to recharge the battery AND boost B+ to allow higher than pack voltage to drive MG1/2 according to power demand.

The converter bucks under regen to charge the battery with a "safe" voltage.
The converter boosts under load to drive the motors.
The generator (MG1) can be used to power the motor (MG2) directly through the DC bus.

So in other words you cannot connect the battery to the original 201V input and run the inverter via the boost inductor. Like "B+ -> inductor -> diode -> inverter" AND expect this to maintain good (>30kW) power output? Or does 30kW just refer to the boost converter actually operating?
And that would mean you can not use the buck/boost stage as a battery charger while using the inverter as inverter.

The '30kW' refers to what the inductor can carry. So if there is just DC passing through it, you can think of it as a wire resistor.
If there is a voltage across it, that will be because there is a change of current. Change of current times Inductance equals voltage. Power is voltage times current, so the higher the voltage at the same current, the higher the power. Hope that makes sense, kind regards.
The 30kW rating is down to the max current the converter IGBTs can withstand, and how effective their cooling is. If you wanted to run the car solely through the converter, you'd need to suitably fuse it to protect the converter. This is one of the reasons why you can drive in battery mode at low speeds, but as soon as you try to accelerate, the engine starts up.

You could use the converter as an interface to a battery charger, if it suits the project, and if the voltages are suitable, but you'd be limited to 30kW again.

IIRC, some Prius converters are smaller than 30kW.

[jalovick]

Update time. Got a CT200h inverter which is exactly the same as a Prius Gen3 inverter on the outside but actually uses the same logic board as the Auris/Yaris inverter. So fitted an Auris/Yaris board, made some simple code to buck the 360v down to 220v to run the dcdc converter, added some DEADTIME! to the settings, installed in the car annnddd....no bangs so far.

Would you mind adding the relevant details to the Toyota OEM page (https://openinverter.org/wiki/Toyota)? I've been trying to document which of your boards fit in what inverters, to make it easier for people to know which one to build or buy.

I'm loving how things are progressing, but I don't have the same level of electronics skill nor access to a workshop to work on anything currently. I hope to fix that soon.

Jamie

[LeonB]

Observations : used the old connection points to see if it would explode. So far not. Will update on this.

Has there been an update on this anywhere? In the recent videos of the E39 it seems you are still using the old connection points, so I guess there haven’t been any problems so far?