Electric Assist Project: E-charger (2000 Subaru Outback)

[Daox]

Your batteries aren't likely the source of the lack of amperage going to the motor. Its probably the controller. Most of them have thermal limiters so when you mash on the throttle and heat it up it limits amp output to stop from frying itself. You need to find a way to cool the controller, or get one that is made to handle higher amperage. When you are looking at controllers, you need to not just look at peak output, but at the different ratings over time (5 min rating, 30 min rating, etc).

Sorry to hear it didn't work out, but I have to agree with Frank. Unless you have a pure EV mode for cruising, you're not going to see much of any benefit because your engine is already way oversized for cruising efficiently.

[bwilson4web]

One 'mind experiment' would be to rig up an rpm-to-assist control system that would add electric boost in proportion to the inefficiency, power range of the ICE. The idea is if the engine is in a fuel inefficient region, add electric boost to offload the engine. But as the engine reaches fuel efficient ranges, the electric power backs-off.

Just a random thought,
Bob Wilson

[gor]

Bruce, could you post again data on your 2.5L Outback? (i can't find it in the thread)


2. remember, Ben Nelson experimented with alternator on/off? FE without - 10-15%

3. another link - electrocharger from Sigma Automotive
Electrocharger / Retrofit Hybrid :: Sigma Automotive


yea, major challenge now - integration, - make systems to assist, not to play tag of war against each other

manual trannys and older cars with less electronic control would be better (easier) for DIY BAS? would it present some another, different challenges?

[brucey]

I still have the system running, and have been driving with it still. As a result, I have more thoughts to give out on this:

Basically, the mileage is going to be the same at any given RPM/speed. So the best thing I've found to do is to give the E-charger full throttle, accelerate up to speed, then get it into top gear ASAP. Once that is done let off the throttle so the car is still moving, but starting to slow down. Apply power from the e-charger so it maintains speed (50 amps or so it seems to like, more continuous and it will limit itself)

That's basically how I've been driving. With some luck, I've managed some 40 MPG city runs, although once again, that's with heavy electric subsidizing. So I know it's not the most efficient way to do things. Regular seems to be in the 33~38 range for short city trips.

Compared to 18~23 I usually get for city, I'd happily call this a success. Just wish I could do more as I basically want a setup similar to the volt that can displace my city gas usage almost entirely.

OH! Also. For anyone wanting to do this from a purely (Jeremy Clarkson voice) POWERrr standpoint.. Yeah, I think I might have one of the fastest 4 cylinder N/A Outback on the planet right now. It's still not what I call fast (I've ridden a ninja 1400, and own a 600. Driven plenty of American muscle as well.) But for a daily driver it's snappy to say the least. I'll try to get a video of the 0-60 with and without the E-Charger helping.

Which reminds me, at least according to idle, with the system disarmed I see no loss in mileage over regular driving. With it armed and spinning (But doing nothing else) It seems to do a little regen (3 amps) which of course drops mileage by a few %.

[dcb]

That is definitely an improvement So the strategy around town at this point is to accelerate with heavy throttle AND echarger? thereby nullifying the "cost" of having the electric motor turning the engine while keeping the engine in decent bsfc, but resulting in rapid acceleration?

The only question I would have then would be how much more difficult would it be to drive a wheel and what would an optimized strategy yield in mpg improvement there? How about an e-wheel that you can raise on demand as a possible next step?
E-wheel for any vehicle - MIMA Honda Insight Modified Integrated Motor Assist

[andylaurence]

I wonder if the most economical solution would be to use the motor for regen on acceleration and then use the accumulated power for extending your coasting. That makes best use of the engine, which is more efficient under wider throttle openings.

I'm very impressed with your project. I've been keeping an eye on it as I plan to do something similar but with a Jeremy Clarkson bias! I'm looking at fitting something to my race car for a bit more grunt.

[brucey]

Alright, I'm calling this project a success, but since I can't do EV Glides, I will be re-configuring it and have started to dismantle it for now. Wanting the extra room next to my leg more than anything.

I'm also not opposed to the idea of an EV car with this, but don't know how it would work out with a small motor and many steep Morgantown hills. Regardless, school starts back tomorrow, so I probably won't have a lot of updates on this until things slow down a bit.

[Frank Lee]

Is there enough test sample to really say it went from 18-23 to 30-35? I would be happy to be wrong about my thinking on electrochargers if they do nearly double fe...

[brucey]

That was one of my better city trips.

Other than the scangauge reporting orbital numbers I don't have any data, and I'm sorry for that. I know it's policy to do it here. The scangauge usually within a few % of actual tank fills, but it's hard to do an A B A on something like this, as the variables are still there even doing that method. I think the huge increase came because I figured out how to use it properly and I was subsidizing the gasoline use heavily with electricity. Other hybrids are not currently doing this, they're mainly using the electric for regen abilities.

[Frank Lee]

As we are seeing on the Vetter competitions where the goal isn't the most efficient vehicle, but the vehicle with the cheapest energy cost, perhaps you still come out ahead money-wise by having cheaper electric power in the mix even if the gas engine efficiency may have been reduced.