convert vectrix to run on portable gas generator

what do you mean by converting? I posted a while back that you can use a Honda EU2000i as a charger. This 42lbs generator is very quiet and produces enough output to charge the Vectrix if you are in a pinch. In fact, I use mine as a recovery tool. If I get stuck, my wife can drop it off. I recharge a few bars and strap it to the back of the Vectrix and drive home. I can't see how one might put it in place of the actual battery pack. Just not enough output.

Doing as you propose is not practical, unless you have a small 20 to 30 KW generator! Under hard accelleration, the Vectrix requires around 25 KW! (Maybe a small gas turbine alternator, with 250 ampere, 140 volt D.C. output?)-Perhaps a better way would be to adapt a 5 KW generator to charge/extend the milage of the battery pack, retaining the battery for the high current demands of hill climbing and acelleration. Peak horsepower of the Vectrix is over 20 horsepower, that kind of power is not usually available from a small, or lightweight, generator system.-Bob

Wiring would be the EASY part! A D.C. voltage, of 135 to 155 volts, at 250 amperes, would need to be supplied to the battery connectors, then the battery could be removed. Use of a lower current supply would result in excessive voltage drop during acceleration and hill climbing. Regenerative braking would need to be disabled, and software modified. Have you ever seen/priced generators of this size? It is NOT practical to operate the Vectrix directly from a generator, without battery!-Bob

During 2006 vectrix designers assured me that they will enable a SW option to allow battery recharging while riding, with energy sourced from a petrol generator. At 40 km/h, energy drawn from the battery had to be the same that could be recharged from the generator, therefore as long as you have petrol, the range was near infinite. At 70 km/h range should have been around 120 km. After purchasing the Vectrix, the SW option never apperared. In the end I sell out my honda EU20i portable generator, as it was completely useless. If i ever get stuck, there was a plug nearby... The city is full of plugs...
On the other hand, there is a suplementary charger program and hardware installed on the vectrix, wich was suppossed to work with the fuel cell. if you can tap in it, maybe you can use a 500W small, quiet portable generator to extend your range...

i have actually done a fair amount of research on this so here are my thoughts and findings.
the hardest part was locating a small (efficent) 4 stroke motor to convert to LPG, the reason for the 4 stroke is the ease of the conversion. there are companies that have developed LPG carberettors for these motors, from memory i had calculated that to run a small 25 - 40 amp alternator you would require a minimum if 1.5hp or a 40 - 50cc motor. my theroy was to feed the alternator rotor with 6 to 12VDC via a yet to be built regulator.

theroy goes that if you look at the output of an alternator not connected to a battery its voltage would be between 100vdc and 160vdc depending on the rpm's applied to the rotor. this means that the resistance of the battery then draws the the voltage back to 12vdc with the leftover voltage being converted to current via the ohms law.
how ever as you increase the voltage you gain effeciency and because there is also inductance and frequency involved (stator of the alternator)and its primary ac voltage the losses in curent from increasing its base voltage from 12 to 125vdc are not that easy to work out however the efficencies gained means that you require less horsepower to drive the alternator.

there is pleanty of information on the web on this subject its well worth a look.

so i have my alternator i was thinking of one from dihatsu shrade, small, internal fan, light weight, the next bit is the motor, as it happens honda released a range of small 4st motors on whipper snippers and other garden tools, the problem is the size (cc's) are too small but im sure its only a matter of time before a 50cc 4st motor comes on to the market.

the third issue is that of gearing, in order to gain maximum power from the engine i would expect it will need to doing around 6000-7000rpm, and the alternator will need to spin at around 3500 - 4000rpm.

my paln was to mount this on to a plate an attach it to the top of the battery box between your legs. from there run cabled from the alternator to the batteries.

under normal city riding at 60kph the vectrix draws around 7amps, so to extend the range dosent require much input from an external sorce. the planned fuel cell only had a 500 watt output.

yes the vectrix is capable of drawing 20kw but this is only for a matter of seconds at a time as the motors ability to dissapate the heat generated is limited when talking about theses types of currents. normally the current draw as said before is around 4 - 9 amps or 500 - 1125 watts at 125vdc.
i hope this helps.
cheers, paulyd

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under normal city riding at 60kph the vectrix draws around 7amps, so to extend the range dosent require much input from an external sorce. the planned fuel cell only had a 500 watt output.

yes the vectrix is capable of drawing 20kw but this is only for a matter of seconds at a time as the motors ability to dissapate the heat generated is limited when talking about theses types of currents. normally the current draw as said before is around 4 - 9 amps or 500 - 1125 watts at 125vdc.
i hope this helps.
cheers, paulyd

I believe the current draw at 60km/h must be much higher.

Say you were lucky and had a good battery, you might get 80km range on flat ground at 60km/h constant speed.

That would take 100min to empty the 30Ah in the battery at that speed.

30Ah / 1.333h = 22A

That's around three times your estimate.

Under real city driving conditions you will not cover the 80km at 60km/h in 100min, of course. It might take a lot longer, depending on how long you stand at traffic lights. That gives the generator extra time to recharge the battery, but I imagine it would be very uncomfortable to have a generator running at optimal load between your legs at the lights.

But the accelerations will cost much extra energy.

In short, I think the on-board generator idea is only feasible if the majority of the charging is expected to be done whilst the Vectrix is parked.

And then there is the safety problem: Imagine crashing with a running 150V generator between your legs!