openinverter forum

I am curious about building a hybrid system with a configurable AC generator (15-18kW), a 3phase motor (auxiliary motor, NOT a traction motor), and a battery pack.

Would the Toyota / Lexus inverters with their dual A/C connections be a good choice for this design? I believe each unit actually contains 2 inverters meant for MG1 & MG2 respectively. But...

Would the aux motor be able to use power from the generator or the battery pack?
Would the aux motor be able to use power from the generator AND the battery simultaneously?
Would power from the generator be available to recharge the battery as soon as the motor isn't using 100% of generator output?

I have researched these inverters some, but still not sure of their capabilities when it comes to a use case like I'm describing. Thanks for any thoughts or links to other relevant threads or articles!

Would the aux motor be able to use power from the generator or the battery pack? - Yes
Would the aux motor be able to use power from the generator AND the battery simultaneously? - Yes
Would power from the generator be available to recharge the battery as soon as the motor isn't using 100% of generator output? - Yes

this is how a Hybrid works.

Would you want to use this in a car? If so, can’t you just use the power split device of a Toyota transmission to achieve what you want?

Couple an ICE engine with a governor to the bell housing, and start it. Now, apply regen to MG1 via some input like a potentiometer on a dial. You are now using the ICE engine to charge the battery - as long as the torque applied by MG1 does not exceed the torque required to move the vehicle.

Now, send throttle signal to MG2. Now you are moving. Some of the kinetic energy to move is coming from MG1 (but not enough to get it moving on its own) and the rest is coming from MG2.

My thinking on this matter is that the controls are not the hard part. The hard part is coupling an ICE to the transmission, and fitting it in a space where the ICE can get adequate cooling without introducing a whole lot of complexity. Perhaps in a car that originally had a transverse layout it wouldn’t be too bad, but for a rear engines vehicle or longitudinal vehicle it would be really hard to achieve.

Scrappyjoe wrote: ↑Wed Jan 28, 2026 11:08 am Would you want to use this in a car? If so, can’t you just use the power split device of a Toyota transmission to achieve what you want?

Couple an ICE engine with a governor to the bell housing, and start it. Now, apply regen to MG1 via some input like a potentiometer on a dial. You are now using the ICE engine to charge the battery - as long as the torque applied by MG1 does not exceed the torque required to move the vehicle.

Now, send throttle signal to MG2. Now you are moving. Some of the kinetic energy to move is coming from MG1 (but not enough to get it moving on its own) and the rest is coming from MG2.

Thanks for the responses! I have built an EV with it's own dedicated inverter and drivetrain, so that part is settled. I am thinking about having it tow a trailer with a generator, an inverter, and an auxiliary motor to run a machine mounted on the trailer. I'm thinking the inverter would connect to the EV traction battery via Chademo protocol (inlet port currently mounted on the rear of the vehicle) to allow 2-way power flow so the generator could charge the vehicle or the vehicle could power the aux motor. So my question is more about best inverter selection for this application, rather than a design/ build-from-scratch. I am guessing the Toyota / Lexus inverters will be a good option here but not sure if a certain one is better suited or not. I do have a zombieverter board that can manage the inverter.

My guess is that, if you are going to use the Zombieverter, it doesn’t really matter - you’ll be using canbus so you’ll be limited to the OEM capabilities of the inverter on your trailer. Just bear in mind (I think) the zombie needs a paired inverter / motor - no using a Prius inverter with a leaf motor I think.

There has been some discussion on this forum about how the i3 Rex is implemented, and it appears to be pretty much what you are looking at - an ICE, coupled to an EV motor, connected to an inverter, separated from the rest of the componentry by a contactor set with a precharge circuit.

Just today I saw a forum discussion on how to set the output DC voltage of an openinverter controlled inverter and johu said it is straightforward to implement via regen settings.


Ah, now I remember - it was a thread on implementing a series hybrid with no engine (sorry I’m in my phone you’ll have to search for the link)