Lexus Inverter Hacking

[Jack Bauer]

Sorry forgot about this I'll post some info in the morning when I'm in the workshop.

[Jack Bauer]

Figured I'd forget in the morning so grabbed my notes. Of course my pos scanner won't work with Linux so snapped a few photos. Hope it helps. In the photo you can see the two grey wires carrying the pwm signal and the green wire is +12v. iirc you may need to bypass a transistor on the back of the board to enable the booster. I'll try and get a few better pictures.

[Jack Bauer]

You'll need to tap the 50 way connector to get the hv and lv bus measurements.

[xp677]

Thanks Damien, I'll have another look at my setup.

I am using the same pins as your grey wires for PWM high and low, and am pulling the HV (inverter side) voltage from the same pin of the 50-pin connector as in your notes.

The green wire which you have as 12V, for me that's a 0-5v signal for the LV (converter input side) voltage. This also matches up with your pinout drawing for the connector. There is 12V present at the other end of the JST connector, again this matches your pinout drawing.

With this in mind, I don't have any notes on enable pins for the converter. I hope I'm just missing something simple. Here's what I have so far. Hopefully bypassing this transistor will get it to power up. Right now I'm getting no sign of life from the converter.

The LV voltage is passing straight through to the HV, this is to be expected, as it will be passing through the reverse diode on one of the IGBTs.

[xp677]

I thought you guys were purposely bypassing the boost converter as it would be to limited in power, and work with a battery with a higher total voltage.
I should do more reading and watching all the videos I guess.

The purpose of the converter in my project is to convert the 650V battery pack to a more manageable voltage (around 300-350V) to run a DC-DC converter, heater, and take voltage from a charger to charge the batteries. None of this will require more power than the converter is capable of handling, making it a good choice. We would need to convert this voltage somehow anyway, might as well use the inbuilt converter rather than leave it unused.

[Jack Bauer]

Here is a look at the back of the board with the enable line. The yellow wire needs to be pulled to ground if memory serves. I'll power it up over the weekend and confirm.

[xp677]

Thanks Damien, that's great.

[RE3Rotor]

So we cleared up the myth about Toyota motors (not) needing 600+V. Is there a reason I cannot run the GS450h MG1 & 2 using the Gen 3 Prius inverter? I am leaning towards that because of 1) the cost, 2) built-in DC-DC converter, and 3) looks like it supplies power to the electrical AC compressor as well.

[Thatguyoverthere]

So we cleared up the myth about Toyota motors (not) needing 600+V. Is there a reason I cannot run the GS450h MG1 & 2 using the Gen 3 Prius inverter? I am leaning towards that because of 1) the cost, 2) built-in DC-DC converter, and 3) looks like it supplies power to the electrical AC compressor as well.

It can be done, but you would need to change the connectors for the motor that connect to the inverter. As for the dc-dc converter, I believe all the Toyota hybrids have it built in to the inverter/converter. Check out the other gs450h threads, I believe xp77 got his motor running using the 2007 Camry hybrid inverter and Damien's VCU.

[JaniK]

The Toyotan/Lexus inverters seem great if they can do all of this:
AC-DC Charging battery
DC-DC converter to 12v
DC-AC motor inverter

If I understand correctly, they will eventually do it openinverter style

[RE3Rotor]

It can be done, but you would need to change the connectors for the motor that connect to the inverter. As for the dc-dc converter, I believe all the Toyota hybrids have it built in to the inverter/converter. Check out the other gs450h threads, I believe xp77 got his motor running using the 2007 Camry hybrid inverter and Damien's VCU.

I went back and read more carefully and Damien confirmed the inverter does not have DC-DC converter. Running an external one is not that big of an issue. I just wanted to see if I can get everything in an all-in-one package.

Boosting from 20v to 250v. The gs450h inverter does not have a dc dc built in. Its just a dual inverter and boost converter. Rated at 37kw from what I can find online.

[Kevin Sharpe]

I just wanted to see if I can get everything in an all-in-one package.

Recommend you take a look at the Tesla Model 3 PCS which combines a ~10kW charger with a DCDC converter. We're using it on several vehicles and it will be one of the key components on the LEXI reference build. I've paid as little as 100 (USD) for PCS with cosmetic damage.

[RE3Rotor]

Recommend you take a look at the Tesla Model 3 PCS which combines a ~10kW charger with a DCDC converter. We're using it on several vehicles and it will be one of the key components on the LEXI reference build. I've paid as little as 100 (USD) for PCS with cosmetic damage.

Something like this? I will keep looking to see if a cheaper one comes up.

https://www.ebay.com/itm/TESLA-MODEL-3- ... 8230!US!-1

[Kevin Sharpe]

Something like this? I will keep looking to see if a cheaper one comes up.

Yes, but don't pay retail prices

[Cyruscosmo]

Hello all.

I have a question for you. Would it be possible to use this "inverter hack" to power only the larger of the two motors from the GS450h transmission case for acceleration and regen braking/battery charging?

What I would like to accomplish is adding an electric assist and regen braking to my truck making it like a hybrid except that if the system goes dead the truck will still function.

What I would like to do is as follows. Remove the larger of the two motors from the GS450h case along with supporting hardware, build a new case for the removed GS450h parts and then install this device between the transmission and rear differential of my truck.

The 4x4 version of my truck has a transmission with a rear flange that the transfer case mounts too. I would like to mount the new GS450h motor case in place of the transfer case in my two-wheel-drive truck essentially turning the whole thing into a hybrid without it being an actual "Hybrid".

My reason for doing this is that Washinton has recently jacked up the licensing fees for electric and hybrid vehicles. I thought the whole point was to encourage people to buy electric and hybrid vehicles. Anyway, I sold my electric Geo after the price hike and have been following this thread since day one having followed Damian over here from the Open Revolt forums. It is time I get into the AC Drive game.

[Alexstarex]

Million-dollar question - Does the Toyota inverter not use charging?

or in the car you need 2 inverters
1. DC-DC
2. charging?

[sfk]

My understanding is that you can jack an AC line into 1 of the inverters and treat it like you are brake regenerating to charge the battery. I guess you could use both inverters if the batteries can take it.

[sfk]

Remove the larger of the two motors from the GS450h case along with supporting hardware, build a new case for the removed GS450h parts and then install this device between the transmission and rear differential of my truck.

Really not sure how you plan to "build a new case" for this motor. It's not impossible if you have the ability. More info would help.

[Alexstarex]

Remove the larger of the two motors from the GS450h case along with supporting hardware, build a new case for the removed GS450h parts and then install this device between the transmission and rear differential of my truck.

Gearbox from prius is suitable for these purposes.

[jnsaff]

The 4x4 version of my truck has a transmission with a rear flange that the transfer case mounts too. I would like to mount the new GS450h motor case in place of the transfer case in my two-wheel-drive truck essentially turning the whole thing into a hybrid without it being an actual "Hybrid".

Why not just use the MGR on the rear axle? Rebuilding a motor case seems like the mother of all rabbit holes.

[xp677]

Million-dollar question - Does the Toyota inverter not use charging?

or in the car you need 2 inverters
1. DC-DC
2. charging?

In the Lexus, the only way to charge the batteries is from the two motors. Either from regenerative braking, or from the engine. There is no charger.

[Alexstarex]

Million-dollar question - Does the Toyota inverter not use charging?

or in the car you need 2 inverters
1. DC-DC
2. charging?

In the Lexus, the only way to charge the batteries is from the two motors. Either from regenerative braking, or from the engine. There is no charger.

thanks

[xp677]

So we cleared up the myth about Toyota motors (not) needing 600+V. Is there a reason I cannot run the GS450h MG1 & 2 using the Gen 3 Prius inverter? I am leaning towards that because of 1) the cost, 2) built-in DC-DC converter, and 3) looks like it supplies power to the electrical AC compressor as well.

See here for the comparison, the Prius inverter is not as powerful

https://www.osti.gov/servlets/purl/928684

There is a similar document for the Prius

https://info.ornl.gov/sites/publication ... b26762.pdf

[xp677]

My understanding is that you can jack an AC line into 1 of the inverters and treat it like you are brake regenerating to charge the battery. I guess you could use both inverters if the batteries can take it.

This works with Damiens Prius controller as it replaces the logic board for the inverter. For the GS450h inverter we leave the logic board in place. Feeding AC, especially single phase, into a motor output without the resolvers seeing motor rotation may upset the inverter. Toyota goes to great trouble to make these units bulletproof, this is an example of something it likely protects against.

Might be worth a try on your own unit though, and let us know bow it goes.

[xp677]

I believe xp77 got his motor running using the 2007 Camry hybrid inverter and Damien's VCU.

I used a RHD GS450h inverter, and my own controller and code which I shared with Damien, this became the basis for his VCU.

I have a thread about it: viewtopic.php?f=14&t=205