Custom Enginer PHEV (8kWh)

So, are they in parallel to the same leads?

 

Also, I'm not sure if you've noticed any of these issues. Say you're driving up a hill using EV mode(Yes, I understand that the Enginer kit is not meant to do such a task), you've drained the SoC of the traction battery down to 2 bars(Red/Purple). You've finally reached the top of the hill and begin to hold on the brake to capture regen. Does your car capture regen nicely?

When ever I have my Enginer kit activated and I'm attempting to capture regen, it seems that the amount of energy that I could have captured is a lot lower than if I had turned off the Enginer kit.

Are you seeing this issue?

 

I haven't noticed the difference. I seem to regen nicely whether the kit is on or off.

BTW: How is your system working? I know you had some bugs to work out.

JOANNA

 

I assume that my DC/DC is just broken...

I haven't bothered to actually measure the output yet.. I'll replace the DC/DC this weekend..

 

Dave, how come the Prius OEM is not showing the enginer pack bleed-in as leaves on the MFD ?

 

Do you see a lot of green leaves when the SOC is low and you turn on the Enginer system to charge up the stock battery (don't even need to be moving)? I would expect to see them then, unless the system somehow measures "leaves" at the generators.

 

For what it's worth, I only see green leaves when I touch the brake pedal, I haven't don't a controlled study though. I've always thought of the leaves as "regen received while pressing the brake pedal". So maybe it's showing up as "coasting regen" not "brake pedal regen"

The alternative is that I simply don't regen enough to get the leaves

11011011

 

That makes sense, thanks. If the car is sitting with Ig-on and getting a ~ 2 kW bleed in from the enginer pack, a 50 w*h (= to 50*3600 w*s) leaf should appear for every 50*3600/2000, or 90 seconds charging between the MFD updates.

If it works this way, it would be a simple test to verify the extra pack's correct operation.

 

Thanks for sharing krousb, very exciting results! At this point I'll admit I have no idea why this works, but its awesome that it seems to. Looking forward to seeing the 3 converter result. I think its a very good idea to pair a scan gauge with these kits so you can keep tabs on the system since the kit doesn't. In temperate weather just watching SOC is probably ok, but for very hot or very cold weather it would be a good idea to watch CCL and make sure your amps in is always less than this.

Incidentally, I would assume for those with shorter commutes you should be able to run a similar setup with 4kW of battery and 2 converters and get the same mileage for half the range. IMHO the higher output of the 2 converter option makes this conversion a lot more interesting. Getting ~70-75mpg for 60+ miles is great if you need to drive that far often, but for many people spending an extra $500 to get 90-110 mpg for 30+ miles would be much more compelling. I would think the current draw from the secondary pack shouldn't be any worse for 2 converters with a 4kWh pack than one converter and a 2kWh pack.

 

FWIW I still think it would be nice to pair this kit with a CAN-View. The CAN-View lets you view a lot more parameters, and gives you the option of triggering relays based on CAN parameters. It would be pretty easy to wire this to your manual switch on the Enginer kit and specify safe operating ranges for various CAN parameters. That would let you automatically kick the converters off when SOC gets too high, or CCL gets too low for example. It should be flexible enough to even turn one converter off at one point, and the other off at a different point. Its a few hundred bucks more than a SG, but it seems like you get a lot for that extra money for a setup like this.

 

You got me thinking miscrms that a DC-DC converter with adjustable output would be ideal.

Have a short trip again? Crank up the juice! Got a long trip ahead? Crank it down!

Bonus points for being able to fully program it based on various inputs such as throttle, brake, OEM battery charge, ambient temperature, etc.

 

Manzanita Micro's PHEV converter does all that. They use feedback from the CAN-View to dynamically set the output voltage as I recall. Down side is its $2500, for just the converter/charger.

Actually krousb's setup is pretty clever, as he can select whether to have 1 or 2 converters powered on to do exactly as you describe. Ultimately it shouldn't matter for long trips whether you get 100mpg for half the time and then 50 for the remainder, or 75mpg the whole time, but its still kind of cool.

Rob

 

This is the only part of this setup I'm a little worried about. Paralleling 2 dc:dc converters is usually ok as they are pretty much just acting like current sources. Paralleling 2 smart chargers can be tricky, as each one is watching the pack voltage trying to decide when to terminate charging. I would worry a bit about them faking each other out and not fully charging or worse one missing the charge termination cue and overcharging. Do you know what the charge profile is and what they are using for charge termination? If its some kind of peak or dV/dt sensing I would be concerned. If they can get away with just some kind of simple Constant Current / Constant Voltage setup it would probably be ok.

Either way I'd just keep an eye on it the first time you charge and see what happens.

 

.Edit

 

We are facing again the original concept of PiPrius on the DC-DC converter, not a new development only cheaper. With the only difference that the Manzanita Micro converter can handle 40Amps with out hesitation and supports 100% pure electric EV mode as long as the battery source will last.
It worked for me in a daily basis for 9 months in a row until I changed my PHEV conversion to the production #1 BMS+ family of products as a test pilot from Hybrid Interfaces.
This concept really works as a low current buffer to the OEM NiMH. krousdb is taking it a NOTCH up..... with the 8KW.
With regards to the smart chargers, I hope that krousdb is charging his 8KW pack in 2 different sections, meaning two 4Kw LiFePO4 to take full advantage of a fast charging procedure with 2 smart chargers that will NOT interact withing each other under the same load.

DRESS, jump to the ManzanitaMicro web site and get familiarized about the PiPrius concept of operation or the same information in to the EAA-PHEV archive files .