Search found 86 matches

by unheardofinstruments
Tue, 12 Feb 2013, 02:25
Forum: EV Motoring
Topic: New battery technology?
Replies: 20
Views: 3238

New battery technology?

I may be wrong but my understanding of it was that supercapacitors / ultracapacitors can store enough charge to take care of peaks/transients and allow the battery to be used at much lower discharge rates and more continuously which lengthens the life of the battery significantly, CSIRO had worked o...
by unheardofinstruments
Sat, 09 Feb 2013, 17:59
Forum: Technical and conversion discussion
Topic: Soapbox on regenerative braking
Replies: 278
Views: 29331

Soapbox on regenerative braking

second law of thermodynamics begins with `in a closed system...' the bit everyone forgets about. There is no such thing as a closed system, it is at best a special case. Over unity only means there is an energy input from a source not accounted for in the experiment. for instance the Adam's motor wa...
by unheardofinstruments
Fri, 08 Feb 2013, 06:02
Forum: Technical and conversion discussion
Topic: Soapbox on regenerative braking
Replies: 278
Views: 29331

Soapbox on regenerative braking

This is something that I had thought of ages ago, well explained. I wonder if it could be as simple as driving 3 coils in a four coil motor and using one to charge.

http://www.davidicke.com/forum/showthread.php?t=159243
by unheardofinstruments
Fri, 08 Feb 2013, 05:40
Forum: Technical and conversion discussion
Topic: Soapbox on regenerative braking
Replies: 278
Views: 29331

Soapbox on regenerative braking

I am now considering moving my hydraulic regen from the range extending trailer to the front shaft on the motor in the car as I have nothing on it at present having crippled the power steering and made it manual and I will probably like it when I am doing short trips too, lots of hills around here s...
by unheardofinstruments
Fri, 08 Feb 2013, 04:59
Forum: EV Motoring
Topic: New battery technology?
Replies: 20
Views: 3238

New battery technology?

http://www.battery-solutions.basf.com/p02/USWeb-Internet/battery_solutions/en_GB/ details various BASF work this is a good overview of a few of the different approaches being worked on; http://www.popularmechanics.com/cars/news/fuel-economy/8-potential-ev-and-hybrid-battery-breakthroughs#slide-1 The...
by unheardofinstruments
Tue, 05 Feb 2013, 05:09
Forum: EV Motoring
Topic: New battery technology?
Replies: 20
Views: 3238

New battery technology?

supercapacitors made of graphene, looks like absolutely everything will be made of the stuff soon.
by unheardofinstruments
Mon, 04 Feb 2013, 16:08
Forum: Technical and conversion discussion
Topic: Soapbox on regenerative braking
Replies: 278
Views: 29331

Soapbox on regenerative braking

The Agni R series are reinforced so rev out to 6000 rpm instead of 4000 and 30kW over 22kW peak and all of their motors have the upgraded design Cedric planned for the E-tek/Mars/LMC motors (before he got shafted) providing higher torque per amp and a speed per volt making the gear reduction ratio ...
by unheardofinstruments
Mon, 04 Feb 2013, 04:26
Forum: Technical and conversion discussion
Topic: Soapbox on regenerative braking
Replies: 278
Views: 29331

Soapbox on regenerative braking

It has been frustrating getting any answers to price inquiries but Agni at $3000 (800 freight) for two 95R motors which would be ok for a lightweight car are the best so far and they have prototyped and tested their soon to be released 300mm high torque version. Waiting to see. http://www.gkn.com/dr...
by unheardofinstruments
Sat, 02 Feb 2013, 08:22
Forum: Technical and conversion discussion
Topic: Soapbox on regenerative braking
Replies: 278
Views: 29331

Soapbox on regenerative braking

To my mind AC or DC is less appealing than a big axial flux PMDC for the following reasons; -mostly the weight savings -overclockable to not need reduction in the drive train thus even more efficient and light -much less back emf so high speed is good -simpler -smaller -cheaper -DIY capable, both co...
by unheardofinstruments
Sat, 02 Feb 2013, 06:33
Forum: Technical and conversion discussion
Topic: NCOP14 on emergency disconnect
Replies: 2
Views: 1132

NCOP14 on emergency disconnect

The relay won't work if there is a 12V supply or other wiring fault which worries me a bit. I kind of like the mechanical switch as a surety.
by unheardofinstruments
Sat, 02 Feb 2013, 06:23
Forum: Technical and conversion discussion
Topic: Multiple Motors vs Transmissions
Replies: 21
Views: 3546

Multiple Motors vs Transmissions

It also occurred to me that a permanent magnet dc motor with suitable overclocking could get 10 times the torque with no reduction drive at all but a pretty large diameter might be needed. I would have to build them myself it seems but it is possible and not overly hard. Getting the right magnets is...
by unheardofinstruments
Sat, 02 Feb 2013, 05:50
Forum: Technical and conversion discussion
Topic: regenerative brakes
Replies: 22
Views: 3103

regenerative brakes

hydraulic regen is twice as efficient, 80% vs 40% and very simple, motor and pump is one unit, pumps against an accumulator, drives from it back to the reserve tank. I got a suitable gear pump for 80 bucks on ebay. Hoses and fittings cost a lot but a friend has the gear to make them (works on heavy ...
by unheardofinstruments
Tue, 22 Jan 2013, 06:23
Forum: For Sale/Wanted
Topic: free to a good home *revised* 350 x 1.2v 40Ah
Replies: 11
Views: 624

free to a good home *revised* 350 x 1.2v 40Ah

What aircraft motor generators? Wattage? The only trouble with NiCad is the possibility of contaminating your neighborhood in case of fire with cadmium. I don't know of anywhere that recycles them, does anyone? They are meant to be good for around 25 years. I know someone who has bigger cell blocks ...
by unheardofinstruments
Tue, 22 Jan 2013, 05:37
Forum: General EV Discussion
Topic: Raising the subject of range extending trailers
Replies: 67
Views: 8466

Raising the subject of range extending trailers

I have been working on the hydraulic regeneration side of the range extending trailer idea today, sizing pulleys and magnetic clutches from AC units for the generator set too, I need two stages of reduction it seems but i haven't given up nutting it out further yet and found a very large pulley but...
by unheardofinstruments
Tue, 04 Dec 2012, 06:52
Forum: General EV Discussion
Topic: Raising the subject of range extending trailers
Replies: 67
Views: 8466

Raising the subject of range extending trailers

Here is one of those little lightweight trailers in fiberglass mentioned at a $600 asking price it seems great. I wanted to be able to sleep in mine but this looks ideal for a range extender, it is even streamlined ok. http://www.ebay.com.au/itm/221152532597?nma=true&si=w0qIjH%2FuC%2BqqMX3qlOPRVpVJL...
by unheardofinstruments
Tue, 04 Dec 2012, 04:55
Forum: General EV Discussion
Topic: Ha haaaaaaar
Replies: 4
Views: 977

Ha haaaaaaar

How much?
by unheardofinstruments
Tue, 04 Dec 2012, 02:56
Forum: Technical and conversion discussion
Topic: Direct Drive: Do I have enough torque?
Replies: 61
Views: 7558

Direct Drive: Do I have enough torque?

A two speed box & differential sounds like a good drop in replacement for the 924 transaxle, I would be keen to hear how it goes, sounds great. The infinite ratio torque converter would allow a much weaker/smaller motor and it isn't any more complex than a diff/box to make by the looks of it, ask yo...
by unheardofinstruments
Mon, 03 Dec 2012, 08:51
Forum: Technical and conversion discussion
Topic: Direct Drive: Do I have enough torque?
Replies: 61
Views: 7558

Direct Drive: Do I have enough torque?

Cool planetary drives want the other 8? (minimum order of ten, not sure how much $ the ones we might require would be) but a great find, ones I have found have all been quite expensive by comparison so far. They can be salvaged from some automatic gearboxes, Craig from turquoise energy did just that...
by unheardofinstruments
Sat, 01 Dec 2012, 19:19
Forum: Electric motors and controllers
Topic: Regen braking bridge rectifiers
Replies: 59
Views: 11748

Regen braking bridge rectifiers

subscribing to this thread
by unheardofinstruments
Sat, 01 Dec 2012, 19:15
Forum: Technical and conversion discussion
Topic: Direct Drive: Do I have enough torque?
Replies: 61
Views: 7558

Direct Drive: Do I have enough torque?

I have been toying with building my own large diameter axial flux pancake motor so i could bolt it directly to the cv and not need a reduction drive the magnetic field rotates 7 times faster than the rotor as there are 6 pole pairs and 7 magnet sets this gives 7 times slower speed and almost 7 times...
by unheardofinstruments
Fri, 30 Nov 2012, 18:48
Forum: Technical and conversion discussion
Topic: Direct Drive: Do I have enough torque?
Replies: 61
Views: 7558

Direct Drive: Do I have enough torque?

canberra32; did redex get back regarding the cost of that 2 speed spindle drive?
I have seen a similar one from the phillipines once for US $550 but not as torquey
by unheardofinstruments
Fri, 30 Nov 2012, 18:43
Forum: Technical and conversion discussion
Topic: Direct Drive: Do I have enough torque?
Replies: 61
Views: 7558

Direct Drive: Do I have enough torque?

Running two motors and two controllers in torque control mode instead of speed control mode essentially is trivial in every way but the cost of an extra controller. I kind of liked the idea of two motors in parallel and one controller doing twice the amps in that respect hence why I bought a high po...
by unheardofinstruments
Fri, 30 Nov 2012, 02:08
Forum: Technical and conversion discussion
Topic: Direct Drive: Do I have enough torque?
Replies: 61
Views: 7558

Direct Drive: Do I have enough torque?

I can see a simple reduction drive using belts or planetary or both could do away with the diff as well and use 2 ac motors, one for each cv. Just pick the optimal ratio or have a two stage planetary gear. Still no decision from the engineer if he will allow a car with no diff even better; www.rexre...
by unheardofinstruments
Fri, 30 Nov 2012, 00:55
Forum: EV Racing
Topic: fiberglass body for lightweight racecar rx7 style
Replies: 3
Views: 2494

fiberglass body for lightweight racecar rx7 style

I have found many kit makers selling skirts and flares, bonnets etc not found much about full body shells in carbon or glass much less how much they would cost, anyone got a ballpark figure? I am guessing it would be cheaper to make it here. The materials are worked out by weight and a little work t...