Barbagris
Posts: 237
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Location: Bilbao, Spain

Re: Power appears to be dependent on regen mode

Thu Mar 13, 2014 12:01 pm


Do I interpret this graph correctly if I conclude that the max regen is only about 4.5kW (328V with -120A)?
That sounds very little compared to the Tesla Model S which has 60kW max regen.


Do the math.

328V x 120A = 39360w, or 39 kW. ..
...learning...

PV1
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Re: Power appears to be dependent on regen mode

Thu Mar 13, 2014 1:28 pm

Not sure how you got 4.5 kW. I've seen as much as 46 kW of regen going downhill at 50 mph and slamming into B and hitting the brakes at the same time in 80 degree F weather.

As far as the difference in power, is it possible that it switches to a different inverting scheme that happens to increase efficiency, possibly to a scheme for more powerful regen?
"Bear" - 2012 Diamond White Pearl ES with QC - 2/21/2013
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ZsoZso
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Location: Brampton, Ontario, Canada

Re: Power appears to be dependent on regen mode

Thu Mar 13, 2014 1:57 pm

Barbagris wrote:Do the math.

328V x 120A = 39360w, or 39 kW. ..


You are right. I must have mis-clicked something on my calculator :oops:

acensor
Posts: 362
Joined: Fri Mar 15, 2013 7:17 pm
Location: Southern Oregon

Re: Power appears to be dependent on regen mode

Mon Mar 17, 2014 10:18 am

I tried following this thread, and admire you serious EV geeks determination to not only get to the truth but understand the archane details. Lots of interacting factors here and the devil-is-in-the-details it seems. I think I got lost in the details :?

But I wanted to get to a hopefully simple bottom line of "what mode should I drive in for maximum range" even if the answer is different for, say, city, hilly, and open road highway driving.

Mine is the USA MiEV with D, E, and B modes. Virtually always drive in E figuring or at least hoping the the Mitsu engineers knew what they were doing and "E" stands for either "economy" or "ecology" and would be the most range. I put it in B if going down a steep or long hill (as long as it doesn't do SO much regenerative braking that it slows me down below viable speed.)
And I use D only rarely if I want to impress someone with accelleration. :oops:

So is anyone here saying that settling on E for driving is NOT the best range?
Under some scenarios? And if not how significant is the difference?
Alex
{this message posted with 100% post consumer recycled electrons}
SE 2012 white with blue trim, powered by PV (~65%)
2015 Subaru Forester CVT
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jray3
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Location: Tacoma area, WA
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Re: Power appears to be dependent on regen mode

Tue Mar 18, 2014 10:12 am

Alex, I think you've hit upon what Mitsu won't tell us, which is that no automatic setting is available for max efficiency, as that would require what only the driver can provide- foresight. EVery mode is a compromise. A finely-tuned right foot in B mode can deliver the better efficiency than typical driving in E, but it takes great attention to 'ride the razor' and neither over-accelerate nor over-employ regen. D provides no more power than B, but the least amount of regen, and very light braking in D will provide the regen when you need it, with the advantage of brake lights!
This is how I try to thread the needle:
D- go light on the accelerator and light on the brake
E- don't release the accelerator completely unless you need to slow down
B- light on the accelerator, don't release unless necessary, and forget about the brake pedal until you want a complete stop!

Darn it, now I've gotta go do a test drive to confirm regen levels in D mode......
Adios ;)
2012 i-SE "MR BEAN" 110,300 miles
2016 KIA SOUL EV, 90 kW, 27 kWh, 34k miles
2000 Mazda Miata EV, 78 kW, 17 kWh
1983 Grumman Kurbwatt EV,170 kW, 32 kWh
1983 Mazda RX-7 EV 43 kW 10 kWh
1971 "Karmann Eclectric" EV 240 kW 19 kWh

DonDakin
Posts: 387
Joined: Wed Aug 15, 2012 7:10 pm
Location: Montreal Quebec.....

Re: Power appears to be dependent on regen mode

Tue Mar 18, 2014 3:01 pm

I think that maximum range isn't so much about the drive mode it's more about the driver. The slower you accelerate, the more you coast in neutral and the less you touch the brakes the farther you will go.

For me the rule is to bring the car up to speed slowly and then milk coasting for as long as possible and keep the speed 30-35 mph. Watch the power meter and try to keep the car going with as little power as possible.

That will get you max range. But it's not really a driving technique that you can do most of the time.

So I try hyper mile when I can and for normal driving use all three modes. I use E mode most of the time to ensure I don't accelerate too fast. On the highway it's D mode.

B mode is the most fun mode but it burns range faster. Not because of the mode but because of the type of driving this mode can do. If your in B mode then you are more likely accelerating quick and regening hard. Both of which are fun but kill range.

I really think the modes are just tools to let you drive a certain way. It's up to the driver to drive for range or drive for thrills...

Don......

Don
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Re: Power appears to be dependent on regen mode

Tue Mar 18, 2014 4:47 pm

DonDakin wrote:I think that maximum range isn't so much about the drive mode it's more about the driver.
I agree 100% - Whatever mode allows the driver to keep the odometer + RR number to continue to rise as you drive is the best mode for you. I have always used 'B' mode 100% of the time as it seems to work best for me . . . . but it does require a very steady foot on the go pedal for best results

Don
2012 iMiEV SE Premium, White
2012 iMiEV SE, White
2017 Chevy Volt Premier
2014 Ford Transit Connect XLT SWB wagon, 14,000 miles
1979 Honda CBX six into six

PV1
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Re: Power appears to be dependent on regen mode

Wed Mar 19, 2014 7:15 am

I pretty much live in Eco mode. I like how finely the throttle can be adjusted, and I've gained the ability to guesstimate how much throttle I need at different points in my commute. I can drive most of the way without looking at the power gauge and just glancing at speed every now and then. When it comes to slowing down, it's a game with the driver behind me. I'll usually go light on regen, hit the brake pedal for lights and dump some energy to the battery, then roll up to the person in front, then stop. If there's no one behind, coast in N, then work my way down to B before hitting the brakes.

To get insane regen, quickly put the car in B mode as you move your foot from the throttle to brake pedals and push the brakes to where the friction just comes in.
"Bear" - 2012 Diamond White Pearl ES with QC - 2/21/2013
"Koorz" - 2012 Cool Silver Metallic ES with QC - 1/5/2015
"Photon" - 2017 Bolt EV LT in Orange with QC - 7/31/2017

Solar-powered since 10/10/2013

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