Paul and Sabrina's Cheap 3 Phase Inverter (AC Controller) with Field Oriented Control

[Quattro64]

Thanks Guys,

You're helping me out. Skyking you are right, don't know what I was thinking.

Arber you have an APU in mind? I was trying to piece something like an APU together, i.e. the 1.6 Ecotec TD combined with an EMRAX as the Gen. Not cheap but about the same as a good certified aircraft engine. At least the Ecotec can be had for ~ $5k from a wrecked cruise. Regarding its power curve, max torque is at 2k rpm and max HP is at 2.9k rpm, doesn't seem too bad? This gives it around ~135HP. Should be a useful level for an EMRAX 348.

[arber333]

Originally Posted by Quattro64

Thanks Guys,

You're helping me out. Skyking you are right, don't know what I was thinking.

Arber you have an APU in mind? I was trying to piece something like an APU together, i.e. the 1.6 Ecotec TD combined with an EMRAX as the Gen. Not cheap but about the same as a good certified aircraft engine. At least the Ecotec can be had for ~ $5k from a wrecked cruise. Regarding its power curve, max torque is at 2k rpm and max HP is at 2.9k rpm, doesn't seem too bad? This gives it around ~135HP. Should be a useful level for an EMRAX 348.

I had in mind something like RE100 for cessna excel.
https://www.redimec.com.ar/contenido...25328111_1.pdf
Compact and efficient unit. However its not terribly efficient wheel to well since jet process leaves a lot to be desired.

Also have you seen mazda RX7 or RX8 wankel? It has a lot of maintenance and low life expectancy, but tradeoff is it is impossible to sieze it. Since the "piston" part is expanding faster than casing. In case you ran out of oil you just lose compression until you run out of power.

There is Subaru impreza boxer engine. It was developed for aviation and later adopted for atomotive. Caution they run with reduction gearbox.
https://www.experimentalaircraft.inf...ft-engines.php

Also there is BMW R1150 motorcycle engine. With propper gearing you have very compact unit. Take Off
http://www.ultraligero.net/Descargas..._motor_eng.pdf

Pick what you want and stick to it.
I really think we should link this to another thread.

[Quattro64]

Thanks Arber I will look at all of those. I think you're correct about not cluttering Paul's thread anymore. I'll probably start a new thread when the time comes to put this Drive system together. Re-read this one when it is time to buy controllers.

Yes, I was actually aware of all those choices except the R100, I really want to stick to something Diesel, better performance at altitude and It can also run Jet-A. Also, I really like the great MPG(GPH) of the GM Ecotec 1.6.

[arber333]

Be aware A1 jet fuel is of worse quality than diesel fuel and you have to take that into account. Add fuel filters and water separators etc. Also fuel pump should be 2 one mechanical and one electric. You use electric on takeoff and approach for landing.

[Quattro64]

Thanks Arber for the advice on fuel pumps/filters. I will take note of that for this project.

[metallica]

Originally Posted by thingstodo

Hi! Welcome to the forum!

I don't recall a BMS that Paul has designed. He has designed a 500Amp DC controller, a 1200Amp DC Controller, a 1000Amp AC Controller, a Resolver to Encoder converter board, and a DC/DC converter board .. that I know of.

I would suggest using a BMS that has a good track record, of course. The Leaf BMS is good at monitoring from what I read. I have not heard much about the balancing for the Leaf BMS. The Tesla BMS also has a good track record.

Are you recycling surplus batteries? Or building your own? For your first build I would suggest recycling. It simplifies things and you get results a bit quicker ... if you have the room in your vehicle for pre-built packs.

To talk to the boards in each Leaf module, Woltronix has a 'Leaf Pack sniffer 2' that I have read good things about.

For Tesla modules, EVTV has a board that will talk, as master, to the BMS in each Tesla pack.

Those are the most cost effective solutions that I know about.

I don't use a BMS - I bottom balanced my LiFePO4 pack and manually check the cells every 6 months or so, when I've run the pack low. The recycled cells have been rock solid.

My Leaf cells ... I foolishly damaged the boards while taking the pack apart. So I don't have an operable harness or the monitoring portions ... I check them about once a month. The controller on my Polaris Ranger EV won't start up below 42V. That's about 3V per cell. I didn't bottom balance the pack, I top balanced it so that all of the cells hit 4.1V at about the same time.
The voltage on the pack is not as stiff as the LiFePO4 cells, so when the Polaris shuts down, the cell voltage bounces back to about 45V. None of the cells is below 3V when I have let them cool down, before putting them on the charger.

But I'm just a hobbyist. I don't have a highway-capable vehicle running

Disclaimer: I am not affiliated anyone mentioned:
- Paul and Sabrina, I am a happy long-time customer
- Woltronix, I watch and enjoy his videos but have never purchased anything from him
- EVTV, I went to EVCON one year, and am a satisfied, long-term customer

Hi everybody,

Thank you for your answers to my question Thingstodo and Freebeard. And sorry to delay responding. I have had a quite busy schedule this week and in addition I lost the answer I gave you 3 days ago on the website...

So... in fact I used a wrong term when I talked about "BMS". It was actually the "AC Contoler" I wanted to talk about... It must be believed that I had the BMS in mind when I wrote my post, and I mixed the terms...

Anyway, I read the information from EVTV you mentionned. I found these reflections on load balancing issues interesting, and I will keep these issues in mind when I have to choose a solution for my future system.

I'm studying how I could achieve a vehicle retrofit from gasoline to electricity. I would like to start this project in a few months (begin of 2020). For now, I try to identify all the necessary components and associated prices, and get an idea of ​​the total cost of the operation.

Regarding the motor, I envisage to use a three-phase asynchronous AC motor, with a nominal power of about 25 KW, with the possibility of overloading it for a few minutes at maybe 35 KW or a little more.

In this respect, the Paul & Sabrina's AC controller should be a good choice. So I am looking for the plans and diagrams of this controller, as well as the complete BOM. I also thought, derive a less powerful version, so less expensive, since an intensity of 250A would seem to be enough for my project

Can you tell me where I can get this information? Having never realized this kind of transformation, I would also be very interested in any advice or additional remark.

[Piotrsko]

Not to be negative, but, you want a 1960 style VW motor's worth of power to propel your car. A golf cart uses that power level anymore.

[freebeard]

My own EV conversion is stalled out, but I have a Lexus electric axle from an LX400h.



98lbs, 68hp, single speed 10,000RPM. With a single speed, you want twice the gas engine's power (vs 36hp) and fat cables for starting up. Toyota HSD technology. No clutches to burn out from the microsecond shock loads.

If I were starting today, I'd look for the rear axle from a newer RAV4. It has twin motors and the differential in software, important to me since I spun out on black ice.

[metallica]

Originally Posted by Piotrsko

Not to be negative, but, you want a 1960 style VW motor's worth of power to propel your car. A golf cart uses that power level anymore.

Hello Piotrsko !

Not sure if your post was replying to mine, but I think it could be the case because I suppose that 25 KW can seem to be a very low value for an electric car

The fact is that I would like to perform a first car retrofit, at an as lower cost as possible, then evaluate the solution and see what I should adapt in a second time. A speed of permanent 60 MPH should be enough for my purpose. For the battery I think to target around 15 to 20 KWH, depending on the cost of the different other components (The cost is a key factor for me here)

I calculated that with a 25 KW motor, I could move a medium sized car at this speed (60 MPH). I give you here some estimation that I calculated... Maybe someone can have an opinion about these numbers.

[freebeard]

EVTV have a formula for energy usage [citation needed] that involves vehicle weight times two other factors. The chart uses Cx, not Cd or CdA. That could be power required per square foot of frontal area but probably not.

A Volkhart Sagitta V-2 had 25hp (gas) and would do 90mph with a sub-0.20 Cd but it was (very) small.