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The hypermilers that log LMPG will cringe at this thought, but for those of us that live where frequent power failures are the rule, and find our LMPG in the tank because of our lead finger and lead foot, it presents an interesting option for our hybrid mobile power generators.
My Insight is already so heavily modified, that one more electronics box bouncing around the back will not be a big deal, just one less bag of groceries.
The small 7KW 2 cylinder briggs powered generator I use for my backup power is noisy, consumes lots of gas for the average power needed, and must run at 3600 rpm to produce the 60HZ AC needed to power out homes.
While The 3 phase power directly from the IMA motor generator could directly generate the 60HZ 120/240VAC if passed through the appropriate transformer, it would mean running the motor at a fixed fairley high RPM which would have many of the issues that the small gas generator has, mainley not being able to be throttled down without effecting frequency.
Using the 144V battery as a source with the IMA acting as a generator balancing the load and using MIMA to control the generation rate, we may be able to run the engine at a fairley low rpm, and have MIMA control output power.
The first issue we need to address is how to keep the car in a regen mode when idling and in neutral. The stock system will give maybe 12-20A of regen when in neutral and MIMA fully activated. There seems to be several factors that controll weither full regen is available, possibily a mixture of several conditions.
Joe S and Iam Ian are tinkering with the variables, but have not found the magic combination.
It will be interesting to see if we can get this to work, so we can compare the amount of gas it takes per hour with my standard generator and with the Insight as a generator, both with a peak of 7500 W;)

The newer Honda "inverter-based" generators work very similarly
to a prius, basically control the throttle to generate only as
much DC power is needed, and then invert that into 60 hz AC.
They're *way* more efficient than the traditional 1800 or 3600
rpm monsters. There are a couple of "PriUPS" efforts out there
and documented, i.e. hanging an inverter off the traction battery
and having the car just keep said main battery topped up. Several
more people hang a smaller inverter off the 12V system and let
the car support that, but it's more conversion loss and you can't
get more than one kW out of it.
.
Rumor has it that the hybrid minivans that Toyota only sells
in Japan have, or will have, a couple of kW AC inverter power
from the big battery onboard, so the van can be the portable
office with the computers or construction tools or whatever.
The oil cartel is preventing any of this from hitting these
shores, of course.
.
_H*

This is a mod that I have been watching, although I have a stand by generator wired in here at the house. This should be a simple and light mod in terms of added hardware, and could come in handy, aside from the cool factor. Couldn't there be included a kw's generated indicator, to provide accounting for that energy produced. We would have to add a column in the mileage database. There is a column for kw's used, how about one for kw's generated:D .

Can't be of much technical assistance on this, but I can applaud:woot:

The Insight....what a package she is becoming :bananajump: .

Randall

If the car is at ~1,000 RPMs and inneutral and MIMA is fully active regen will slowly begin to apear and will level off at about 1 Green MIMA LED.... I have not yet been able to perform some other tests ....

1> Like at this Idel speed that 1 Green LED exactly what Voltage is it putting out... I know the Insight Regens up to ~180V DC end so the AC before Rectification might be higher than 180V....

2> If we want 50 to 60hz range and as close to 60hz as we can get then what is the Hz of the Insight AC Produced....

3> 1 Green LED of regen is not very accurate for an Amps number... so I was also thinking if we knew more accuratly how many Amps... this with the Voltage number will give a better idea of how much power we have to deal with...

----------------------------

As for Methods ... I see a few choices....

1> Get a DC-AC Invertor.... all the high efficiency ones I have seen first use a DC-DC Step up to get into the 160 to 180V range and then invert it to AC from there.... Well The High Voltage traction battery is already nicely at about 160V to 180V depending on regen state and SOC.... So you open one of those invertors up and skip the part about DC-DC upstepping from 12V to 160~180V and feed the High Voltage pack dirrectly to the DC-AC part of that invertor .... and presto your done..... The nice thing about this is that the Batteries can handel short as in 2 or 3 minutes bursts of up to 14kW of output..... also the Stock system will automaticly try to maintain the SOC of the Stock batteries.... if the stock Batteries get low the Stock System can pull regen up to 2 bars which shoudl be around 40A or so even at that same low ~1,000 RPM idel rate.... Now if we want to use the Stock system to keep track of the SOC we will need the current to flow to and from the pack as it normally would... which it won't do unless the system is useing the IMA motor... but MIMA can get the System to use all the way up to full 100A assist even in neutral and idel.... so if we do the same thing... then the SOC to and from the battery still gets maintained by the system... we just intercept the current before it actually gets to the IMA motor... preferably before it is inverted from DC to AC ... Unless the AC the IMA runs on is very close to 60Hz then after the Stock Inverter might not be bad either.

2> Intercept the AC coming from the IMA Motor before it gets to Stock Pack and transform it to house Voltage .... The usefulness of this method as Mike pointed to depends on the Hz of the AC produced by the IMA and how much of a load you want to put on ect....

3> How much current will the DC-DC Stock System put out that keeps the 12V toped off? as a 12DC to AC invertor without modification should be able to run at up to that level just my taping off the 12V Battery Terminals and the system will keep everything straight from there.

Hobbit
Interesting, As a non Prius guy, that spent most on my on line time on an Insight specific site, I did not get to hear much about the Prius world.This new forum may give us the opportunity to do much more cross pollination from the technical side.
Iam Ian
You hit that one on the head, Tapping the 144v from the Insights pack into the final HV dc Buss of a standard 12VDC -120VAC inverter should work fine. The problem is that a 7KW inverter is pretty big, and most of the cost is in the DC-DC section.
The 2500 W inverter I purchased when we first started fooling with the Booster system can draw over 200A from the 12V dc buss. Considering it is stepped up by a factor of 10 or more, that would place our load on the 144V at about 20-25A which is reasonable.
The other issue here is that the final stage of the inverters are not isolated, and the regulation seems to be accomplished in the step up stage, so MIMA and full range control of the regen current may be necessary to get any reasonably constant AC
We should measure the frequency of the IMA 3 phase regen signal to see what the rpm to HZ ratio is, since running off the AC would allow a simple transformer to both isolate and set the final AC voltage, but the RPM would also need to be controlled to get the 60 HZ.
Now if we could only figure out how to give full regen control at any rpm in Neutral.
I will be part of the next Up Your Volts at the end of this month, and will make a point of getting a scope on the IMA 3 phase signal to answer some of the questions.
The original thread on this subject :
http://www.insightcentral.net/forum/viewtopic.php?t=3996

Continuing the attempts to get MIMA to induce high IMA charge currents while the car is sitting still ... remember, it did not work if the MIMA joystick was first engaged and then the gas pedal was pushed (the engine stalls out), but if the revs were first raised and then joystick pushed I was able to get two green LEDs at 2000rpm. Well, more bad news: after coming back from a trip I tried to duplicate that test and couldn't get any more regen other than what IamIan described above. I had done the previous test on a cold engine ... just came back from the garage and testing a cold engine was able to confirm that at 2Krpm the second LED comes on, but gradually. This is all a far cry from the four solid green LEDs we can induce instantly while driving and pushing the joystick while easing up on the gas pedal. I still can't help thinking that perhaps it's the MAP signal that controls this. Mike, I forgot how many regen amps each green LED represents...

Hi Joe
Each led in regen is 12.5A, all 4 = the max of 50A.
Yesterday I was demonstrating MIMA to a newspaper guy from Hartford that came over to do a story, I blipped the throttle to rev the engine, while in neutral in the driveway, and pulled back on the stick at the same time, and the regen shot up to full and stalled the engine.
The control system is wierd, sometimes it works and sometimes it does not. I am sure it is quite simple once we figure it out. I still have not put a bypass switch on the transmission switch that tells the car it is in gear, we need someone that has that switch in place to see if that matters.
Today I am working on making my solar boost battery charger terminate charge automatically when the batteries are full. It is difficult to make a solar voltage regulator for 7A at 75V. When I open the circuit, it draws an arc that does not extinguish even with a gap of .25", works like a Jacobs ladder for you old timers like me. Burns the h**L out of the relay contacts in a few seconds.
;)

Sounds like you need to switch off with some solid state elements,
and then maybe open a contactor once current is at zero...
.
Hey, you've got some old homebuilt inverter prototypes kicking
around that you built, right? Any ideas about simply building
a decent synthesized-sine unit that can take anywhere from 96
to 300-some volts in and just do the right thing to produce
120 VAC at some healthy amperage? That would be the thing to
bolt right into a prius, for example, and probably your insight
once you get the engine-powers-regen thing worked out..
.
_H*

Hobbit,
Actually I was testing the relay with a dead short instead of the battery pack, to see what the worse case condition would be. It melted good. I want the safety of a hard contact. I can just see the batteries cooking after a thunderstorm.
It turns out it is only the 20 or so volts of difference between the battery and the solar panel that needs to be controlled. I had a nice 12V coil relay with 3 - 10A contacts I put the 3 contacts in series to increase the opening.
I built up an analog controller for the relay, with a precise setpoint for the voltage cut off. The relay will probably get replaced by one of my power modules once I get some confidence in the circuit.

I have learned a long time ago that the subtleties of getting efficiencies in the 80-90% range in an inverter do not come easy. I am not comfortable that I can design one that efficient, and not with a voltage prescaler that can accept from 144 to 300V. Never re-invent the wheel unless you are prepared to improve it, or you can't afford to buy it.
The 2500 W inverter that I bought early in the booster battery project, had a 12V to 135V dc/dc step up stage, and a pseudo (2 step) sine wave inverter stage on the output. If we stick 144V on the 135V intermediate buss, we would get 2500w of output. we turn the motor only as fast as necessary to do the work most efficiently, and use MIMA to control the buss voltage to produce a regulated 120VAC.
http://99mpg.com/TheBestHybridmix/orderedaninverter/
The inverter was a couple of hundred $.

I had a great time at the Up Your Volts training session in Sleepyhollow NY.
We got to do stuff that we would never try on my car.
One of the very interesting experiments we did was to run a civic hybrid with the whole IMA controller and battery pulled out and sitting on the bench. Not only did it start and run, with no codes????? but we found that the IMA motor/Generator was easily able to output 120VAC by tapping onto two of the three power wires running from the motor generator. We connected some shop lights that totaled 1500W, and were able to output ~85VAC @100HZ in idle, and by reving the engine to about 2500 RPM, we were able to get the voltage to 120VAC, and the frequency was about 160HZ. This was with no electronics, right off two of the three motor leads.
This would indicate that the Insight may also be able to run with out the IMA installed?

nice....

did they change the alternator in some way in the civic... becuase it was my understanding that if you yanked the IMA from either the civic or the insight that you have no alternator fuction and are running spark plugs and headlights and such just from the limited energy stored in the battery.

Nice to know about the IMA motor though....

I hope to go to an up your volts myself some day.... but I don't have even a fraction yet of the understanding of the engine you do.... so I think I will have to get some other classes somewhere in automechanics first... all par for the course though.

The DC/DC was out with the rest of the IMA, so of course the 12V was on it's own.
I am not suggesting that pulling the IMA is something one should try to do, only that it can operate in that mode.
Up Your Volts is only for people in the auto repair business.

Yeagh I emailed Craig Van Batenburg about getting the book and DVD set he has... and asked about the requirements for going to Up Your Volts Events.... and I have to learn a good bit more about automotive mechanics before I will be qualified to go to Up Your Volts.... Oh well.... something else to strive for anyway... Concidering the increasing number of hybrids on the road they should continue to have up your volts or somehting like it by the time I have enough background work / skill / classes to be ready for such a course.... In the mean time I can read about it and look forward to it.