Solar Catamaran 45ft with dual Leaf motor

[yabert]

The leaf motor will do much more than that voltage in regen. There are high voltage options for vesc but not off the shelf, diy route, some shared. It's also a very low ohm motor for a common vesc. I'd be very surprised if an off the shelf vesc lasted very long driving a leaf motor.

Wow! Really? Why?
Interesting. The regen will be almost inexistent with a solar catamaran and will be limited to around 1000 rpm and no torque (propeller freely spinning).
Still a problem?

[jrbe]

Wow! Really? Why?
Interesting. The regen will be almost inexistent with a solar catamaran and will be limited to around 1000 rpm and no torque (propeller freely spinning).
Still a problem?

Surge current and flyback voltage of an EV motor that can do around 300+kw and 400v vs. a motor rated for say a 7.5kw and 80v wound that the vesc would ideally be running. Very different resistance and inductances for the mosfets to deal with. Not my strong area, I could be wrong.

[Romale]

Do you think this can be done with the Leaf controller + openinverter control board?

Yes!

[Romale]

Is there also chance that efficiency of IGBT in 400V controller working at 58V will be lower than mosfets inside 72V controller?

it will work with very high efficiency. even 600 amps will be available to you for a short time. It is much more difficult to get them at high voltage from a Nissan Leaf inverter

[Romale]

This point alone will probably keep me away from the Leaf inverter and the openinverter control board.
The boat should have 30-40 kW available from 2 motors for short burst, but the reality is it will move the majority of time with 5-15 kW from one or two motors.
Low speed is key to have range.

Still, the Leaf motor look like a good contender for this project, but I have now to find proper 72V controllers. Suggestions?

if you need two motors, take an outlander front inverter and two version 3 O.I. boards for independent control of each motor from a common housing.
This inverter has high-quality hitachi 650 V 600 Amp IGBTs, they work perfectly at the highest PWM frequency and have low losses.
that's about how I built the floating house and the battery voltage was 72 volts.

[Romale]

They work with low voltage just with lower efficiency than low voltage mosfet inverters

this efficiency is so SLIGHTLY lower that the huge gain from the price outweighs the huge advantage in the direction of cheap inverters from Outlander, Honda or note-e power.
The very inexpensive rear outlander motors and the front dual inverter will allow you to have an excellent power solution with a mega margin of safety and a huge torque obtained due to the large magnetic surface area of the rotor. In the end, this will provide a more cost-effective solution for battery power consumption than a factory-built bldc motor with halls and a controller for it at the required capacity.
In this video, the Outlander's rear motor, a Honda ima inverter, and a 100 volt battery. look at how he drives on the asphalt in 4th gear))

[yabert]

Awesome!!
Romale I can't imagine what I could do if I had only 50% of the knowledge/capacity you have to reuse inverter
I have to look closely at those Honda or Outlander inverter before spending $ on new lower quality inverter.

[yabert]

As I'm not enough electronically inclined to hack a Honda or Outlander inverter, I plan to take the road of the VESC controller.
The VESC 75v 300A model seem to fit well to drive Leaf or Kona EV motor at low power (5-15 kW) and low rpm (caused of 58V nominal battery).
MK3 model or MK4 model, I don't know.
Based on a simple two email exchange with VESC team, this should work without problem considering proper programming of the controller.

Is there smart people who can explain if there is chance that can go wrong?

[yabert]

Is there smart people who can explain if there is chance that can go wrong?

Like this VESC is rated for 300A continuous, but what are we talking about here? Phase amps or battery amps?
Who care about phase amps? I mean, most who want fast acceleration for their small e-motorcycle or go-kart probably care about this, but for a large and heavy boat, I only care about battery amps.

I ask because I saw that a similar 3shulmotors controller is rated 400A, but only 200 battery amps.
https://3shulmotors.com/product/c350-v4/