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Discussion Starter #1
Reading thru the threads, its generally clear that charging the IMA battery directly is bad because the computer doesn't understand where the extra charge came from and it causes Recal's, etc.

My questions are these:
What if you instead provided a charge (from whatever source... that's a different issue) and your point of connection was spliced into the conductors of one of the regen systems (brakes, transmission)?
Wouldn't it 'fool' the system into thinking it was getting the charge from the inductive system and charge the IMA battery in an acceptable manner?


A possible requirement would be that the electrical system of the car was on.
It might be required to fake the car out that a regen system is 'active' (when its not, if I recall correctly... someone did this with the brake system).
 

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You would have to provide 3 phase AC at the proper frequency, and fake inputs to all the sensors that the ECM and IMA systems expect to see.

With only a 6.5AH battery pack and no EV only mode, it's not worth it even if it was practical.
 
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Aaron Cake said:
You would have to provide 3 phase AC at the proper frequency, and fake inputs to all the sensors that the ECM and IMA systems expect to see.
So the regen brakes and downshifted transmission already provides 3 phase AC at the proper frequency? I was thinking that the power generated by these devices would get converted/inverted/perverted* later on 'down the line'.

*Your suspicion that you weren't dealing with an electrical engineer has been confirmed.

My source of electricity will generate a variable 200-400 watts/6-28 amps or more of electrical energy while driving. I don't know if this approaches what is needed to charge up the IMA battery quickly. This also normally wouldn't mean anything for the Insight... unless you had MIMA installed and configured to use more electricity to power the engine than the stock configuration.
 

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I doubt that frequency or even having 3 phase AC is necessary to properly charge the battery. I strongly suspect the AC is rectified, filtered, and then regulated before it is used to charge the battery.
 

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Troll said:
Aaron Cake said:
So the regen brakes and downshifted transmission already provides 3 phase AC at the proper frequency? I was thinking that the power generated by these devices would get converted/inverted/perverted* later on 'down the line'.
Yes, the traction motor is a 3 phase AC motor. Therefore, when it is acting at a generator, it provides 3 phase at a frequency determined by it's RPM.
My source of electricity will generate a variable 200-400 watts/6-28 amps or more of electrical energy while driving. I don't know if this approaches what is needed to charge up the IMA battery quickly. This also normally wouldn't mean anything for the Insight... unless you had MIMA installed and configured to use more electricity to power the engine than the stock configuration.
Why would you even want to do this? Let's not get into the problems that feeding power randomly into the system would create. :)
 
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I've always been intrigued by the 'Holy Grail' of energy production... that which produces enough energy to feed itself. While I know that its a fools errand... I know wasted energy can still be potentially harnessed (preferably at a higher rate of efficiency than the primary).

I'm toying with the possibility of mounting a small Wind Turbine on the car (location to be determined.. somewhere in the back for several reasons including visibility,drag and aerodynamics). The size would range anywhere between 6" and 4'. Regardless of the feasibility, benefit, etc., the challenge of inputting the electricity remains one of the first challenges. This is operating on the principle (hope) that the drag and weight added to the system will be less than the energy generated by this addition and that the energy can be used.

It seems from reading that it can't be inputed directly into the Battery Module (although the charge would occur during operation so I'm wondering if the BCM would really have a hissy fit or not. It seems that adding the power anywhere past this point is a large hassle/impossible due to the pseudo 3 phase AC involved. I was hoping that the electricity generated by the regen braking wasn't the 3 phase AC, but something simpler (like 12v DC!). Alas it seems its not. Now I'm reduced to the following sources of input.

1) The Battery Module... if the car is running will charging it cause a Recal? Certainly charging it while the car is not running does. It's been stated that the differential between one cell and the other could be responsible for a Recal as well. I was thinking if you tied into the input cable rather than one or all cells that this would get around this problem.

2) Charging the 12v starter battery and eliminating the need for using the reserves of the Battery Module for that purpose. At this point I don't have any idea how much juice a radio, dash, intermittent AC and intermittent headlight uses. This would determine the worth of generating the energy and the size of the turbine that would be needed.

Healthy comments are appreciated... however, unabashed Mockery won't be a surprise.
 

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Troll -

All you will be doing is exchanging more aerodynamic drag / engine load for more electrical output. Since the vehicle has a built in system for doing this (the IMA) adding a wind turbine for while-driving electrical generation would result in a net loss of efficiency. The laws of Thermodynamics will get you every time :wink:
 

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battery

Hi,

I toyed with this idea put with form fitted flexable solar cells instead... the enmd answer turns out ... not with the current computer / battery control system... if a replacement were used maybe ... but there is no rerplacement made that does what this one does so you would be making / designing a new one from the ground up... expensive and time intensive.... for home charging the easest thing to do is drive the car onto a a roller of some kind that can turn the front wheels from a electric motor plugsed into the wall... leave car on and in gear and proceed to use the electric motor to drive the front wheels... Insight will enter fuel cut at some point and regenerative braking will recharge the pack.... but other wise you need to rebuild / replace the Insights electronics.

My 2 Bits
 

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If you could get past the minor legal complications, an RTG would serve excellently as an auxillary battery recharger. :wink:
 

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I am not convinced that charging the Insight externally would result in any problem (of SOC)
How many have had their SOC go from a particular level at night, to be different in the morning.

The battery management is somewhat dumb but not that much.

I am sure that if someone would charge it up to full (which is about 80% of it's capacity), it would simply show full in the morning because of a high end recal.

The only thing here is that it will create more cycling and this could reduce the battery life.
 

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battery charger

the smallest amount of modification I ever came up with..... of course there are much smarter people than me out there.... but other than the powered front wheel rollers.... you could test the AC characteristics coming from the IMA when it is running in alternator mode ... this would have to include Voltage , Current , Frequency of AC etc..... then use a relay or some type of switch to disconnect the IMA motor / generator ..... connect an outside source of AC that exactly matches all properties tested before .... the car will need to be on such that the electroincs can take this charge as they would from the IMA when acting as a alternator / low power generator..... the unknown is how the INSIGHTS on board electronics will deal with a constant charge when normally the car's electronics could change the IMA frequemcy and other characteristics to change the type and amount of power getting in alternator mode..... as far as I know .... no one has been yet willing to make thier Insight the test bed.....

but many others know more than I do....

I plan to eventually get MIMA and add a wheel motor to one or both rear wheels to allow short range pure EV and and plug in Hybrid operation.... but I am 5 or so years yet from being ready to do my plug in hybrid plans.... if all goes as planed....

best of luck.

my 2 bits
 

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Troll, you are asking the wrong question. The question should be can the 12 volt system be run off ann external power source, thus eliminating hidden charging of the IMA. Solar can be used for this, most practically if you have an additional 12 volt battery.

The other question is whether a windmill will provide a net energy gain. The answer to that one is a definite no. Even if the windmill was 100 percent efficient, the battery would waste some of the energy in the process of charging.

You want to do the exact opposite of a windmill which is to reduce aerodynamic drag. This can be done by smoothing the underside of the car, replacing mirrors with video cameras, taping up the seams on the body, removing the rear wiper, modifying the shape of the front or rear bumpers, removing the antenna, hiding the front wipers under a cover.

I wanted to build my own aircraft, so I took an aircraft mechanics course. If you are really serious about making changes to the Insight you should study the appropriate field either on your own or by taking courses. This site is fortunate to have many trained and experienced technical people. In spite of this there have been few technical improvements discovered, as the Insight was designed by Honda's F1 design team and they did a great job.
 

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Troll said:
I've always been intrigued by the 'Holy Grail' of energy production... that which produces enough energy to feed itself. While I know that its a fools errand... I know wasted energy can still be potentially harnessed (preferably at a higher rate of efficiency than the primary).
And that's about the point where I stop listening. :)

I'm toying with the possibility of mounting a small Wind Turbine on the car (location to be determined.. somewhere in the back for several reasons including visibility,drag and aerodynamics). The size would range anywhere between 6" and 4'. Regardless of the feasibility, benefit, etc., the challenge of inputting the electricity remains one of the first challenges. This is operating on the principle (hope) that the drag and weight added to the system will be less than the energy generated by this addition and that the energy can be used.
But why?

And of course, the extra wind drag will far outweigh any electrical energy generated.
 

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The real issue with external power source for Insight battery charging is the SOC determination, and the charge termination. The pack can be damaged by over charging, and the detection of the full condition based on voltage alone is not sufficient to assure proper SOC determination.
Whatever the source of charge current, the charge must be stopped when the pack is full.

The Insights pack is monitored for amps in/out, to determing SOC. The temperature is monitored on the whole pack, as well as on several subpacks. There are 10 taps to measure the voltage of each subpack.

It has been demonstrated that the SOC monitoring hall effect ammeter can be easily fooled into thinking that more charge than actual or less charge than actual is happening.

When I get into fooling with the battery pack, I will hijack the battery voltage monitoring, and SOC amp monitoring signals, and replace them with signals that I generate with a new battery management system. That way with MIMA to control the charging, and my own monitoring system, larger capacity packs could be used, or packs with completely different chemistrys could be used.
Step one is to monitor all pack temperatures, and subpack voltages, as well as determining the SOC indepentantly in MIMA. Then we will have the info to do our own pack monitoring, and charge control. This would be accomplished with another Micro based system just for battery management. The results of this monitoring will allow us to fool the stock system into displaying the correct SOC on the battery bargraph, even if the new pack were of different capacity.
Lots of possibilities.
:wink:
 

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"...fool the stock system into displaying the correct SOC on the battery bargraph..."

I'd be quite happy if it would just drive a different display. Preferably a digitial one that'd show values, not just a simple bargraph.

The more I think about MIMA (waiting impatiently here in the West), the more I've come to think that grid charging might be a practical option. Say you have a 20-40 mile or less daily commute. You could charge the pack at night, and use it just enough to stay in lean-burn mode. Indeed, that might be a future software option for MIMA: have the controller add just enough assist, below some threshold which would vary depending on battery SOC. The idea being that you would try to find an assist rate that gives max mpg over your trip length.
 

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James,

What you are describing is very much how PIMA works. I have set aggressive assist rates and been able to average 120 mpg for around 20 miles. Of course at the end of the 20 miles I have discharged the battery. I have also set less agressive assist rates and averaged well over 105 mpg for over 60 miles. With Mikes changes to the way you set the threshold (ability to jog the level up or down) you can fine tune the numbers to provide just the right ammount of assist and regen. The only thing missing is the ability to plug into another power source for charging the batteries. If it had this it would be very much like what Edrive is doing with the Prius which is priced at over 10K for the modification. Sure Glad MIMA costs a lot less. Have fun, Rick
 

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After readin this thread, I had a flash of "Insight" 8)
What if we could power up the BCM while grid charging, (turn the ignition on, but don't start the car,or induce autostop)so the SOC determining circuits and LCD display were active. A grid charger could charge the batteries through the Battery current sensor, and would register the resultant charge on the LCD Battery charge indicator. A small photo detector placed on the last bar, would signal the charger that you were full, and turn off the charger, and the car. It would probably only take 20 minutes to a couple of hours, depending on the charge rate.
It could work.
Armin have you got your 144v grid charger working yet? Give it a try.

:wink:
 

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I was thinking along similar lines - if the BCM is powered up, and has incoming current of the right voltage & frequency, how would it know (or care) that it's coming from an external source rather than the motor/generator? So it ought to do all the proper battery control steps. For shutoff, there is probably a control signal going to the M/G to tell it what rate to generate at. Capture that, and when it goes to zero, turn off external charge.

Though I wonder if you wouldn't also need a relay or switch, so that incoming external current doesn't also flow through the motor?
 
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