# Using alternator as starter engine



## electric_driver (Feb 4, 2017)

Hi,

I'm building a hybrid vehicle, and for this I need to use (one of) the alternators attached to my internal combustion engine as a starter engine. My initial idea was to just use a starter motor, but since I can't use the retract function of this, it needs the starter engine to remain connected all the time, and (besides that this lower efficiency), it would also rip the starter engine apart due to the sheer force when running at full speed. So obviously I need to use one of the alternators as the starter motor.

The internal combustion engine I'm using is a 17 - 20 HP internal combustion engine. It runs at between 6000 - 7000 rpm (say 6500 rpm)
The most efficient rpm for the alternators (regular running, NOT starting !) is between 4000 rpm and 5500 rpm. So, I'll be using a 65/40 or 65/55 gearing in between the internal combustion engine and the alternators. I'll be using not gears, but a toothed belt for this, probably in a V-type setup. 

The alternators are 2 Leece-Neville 8SC3009ZA's (well actually Prestolites, but these have the same specs as the Leece-Nevilles). They run at 24 Volt (output of the 2 is hence 48 V). Power curves are at 
http://www.prestolite.com/productinfo/alternators/8SC3009ZA/8SC3009ZA_curve.jpg

The batteries the alternators charge will probably be 4 batteries of 12 Volt (with 2,3Ah), in specific, these ones (as they're quickly rechargable):
http://cs-shop.de/LiFePo4-Motorrad-...40A-fuer-kleine-Motorraeder-Roller-bis-350ccm

I'll actually be using 2 sets of 4 batteries, so as to allow running the engine from 1 set, while charging the other set of batteries.

Anyway, the question I have is: won't this damage my alternators (as they're not intented to be run as engines, and I'll be starting (and stopping) the engine a lot), and is the power of the batteries (140 A @ 48 V) sufficient ? I assume so, from the power curve, but I still like to hear a second opinion, and hear that it is indeed possible to run these alternators as engines without damaging them.

If the above won't work, will some other batteries from cs-shop (in particular the 150A @ 12V, with 2,5Ah) be able to do it, and/or do I need still other batteries.

Note that the batteries have so little Ah mainly because I like to keep the vehicle very lightweight.


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## dcb (Dec 5, 2009)

fyi we call electric engines motors. engine typically implies a gas or diesel engine in this context.

aside from that I have no idea what you are trying to accomplish, these problems have been solved a hundred times already, and of course you haven't given us nearly enough information to answer any sort of questions. 

I was going to say you might be able to guesstimate the alternator as motor torque based on the graph, but it doesn't even go below 2000 rpm for some reason, which makes me wonder what kind of starter (from 0 rpm) it would make.

but lets assume the graph as alternator is roughly the same as motor once it is spinning.
so just to test your understanding (and assuming %100 efficiency), what is the torque being put into the alternator if it is making 24 volts and 170 amps at 6000 rpm?


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## electric_driver (Feb 4, 2017)

dcb said:


> fyi we call electric engines motors. engine typically implies a gas or diesel engine in this context.


Yes. I meant in my initial post the internal combustion engine; I edited my post and added "internal combustion" now, so that's clearer.



dcb said:


> aside from that I have no idea what you are trying to accomplish,


The other post I did (http://www.diyelectriccar.com/forums/showthread.php?t=181433 ) were questions relating to the electric engine for my project (the whole (electric engine + alternators + internal combustion engine) would be used in a hybrid kart; see http://hybridkart.altervista.org/)



dcb said:


> I was going to say you might be able to guesstimate the alternator as motor torque based on the graph, but it doesn't even go below 2000 rpm for some reason, which makes me wonder what kind of starter (from 0 rpm) it would make.
> 
> but lets assume the graph as alternator is roughly the same as motor once it is spinning.
> so just to test your understanding (and assuming %100 efficiency), what is the torque being put into the alternator if it is making 24 volts and 170 amps at 6000 rpm?


I doubt I need to calculate out the torque ? Also, I don't want to spin it at 6000 rpm. The maximum would be 4000 to 5500 rpm, but that's even for regular running (not starting). I would run it at the lowest possible rpm for starting. I was thinking of say giving it 5 amps at 48V, hence allowing it to spin briefly at 2000 rpm for starting. I could go even lower, say 1 amp or so.

The main question I have is whether doing this wouldn't damage the alternators. I don't know what type of alternator I have (claw-pole, ...) and whether it is as such suitable for use as a starter.


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## Duncan (Dec 8, 2008)

I could be wrong but I would be absolutely amazed if an alternator would have enough torque to turn a stationary engine

There is absolutely no need for anything like that much torque in its normal operation

A starter motor uses hundreds of amps - an alternator is wired for tens of amps
And more importantly a starter motor is geared down massively - 40:1 at a guess

So at a first approximation an alternator will have about 1/100th the required torque


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## electric_driver (Feb 4, 2017)

Duncan said:


> I could be wrong but I would be absolutely amazed if an alternator would have enough torque to turn a stationary engine


Ok, some calculations for the alternators then:

Power
1 Amp @ 48 V = 48 watt (0,048 kW) -speed is then about 2000 rpm-
5 Amps @ 48 V = 240 watts (0,24 kW) -speed is then about 2000 rpm-
140 amps @ 48 V = 6720 watts (6,7 kW) -speed is then about 3800 rpm-

Torque
0,048 kW @ 2000 rpm gives 0,23 Nm
0,24 kW @ 2000 rpm gives 1,15 Nm
6,7 kW @ 3800 rpm gives 16,84 Nm

How much Nm do I need exactly ?



Duncan said:


> a starter motor is geared down massively - 40:1 at a guess
> So at a first approximation an alternator will have about 1/100th the required torque


I don't know how to resolve this issue; to run in "normal mode", it would be connected with the 65/40 or 65/55 gearing. I can't use 1/40 gearing.
From what I've been told, alternators are nonetheless used for this starting purpose too, in hybrid vehicles. So, if the gearing is an issue, how do the manufacturers of hybrid vehicles solve that ?


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## Duncan (Dec 8, 2008)

Hybrid systems using the alternator have a muckle great alternator - and don't drive it though a dinky wee belt!

As to how much torque it will take to start your motor - remember the old days of starter handles?
They would have a lever of maybe 9 inches and would take at least 100lbs force

So 75 Ft lbs = about 114 Nm

Your motor is smaller - but also higher compression


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## piotrsko (Dec 9, 2007)

Ok I must be missing the obvious here.

Why cant you use the drive motor to start?

It has been my experience that you need 1 -2 hp for starter motors at about 100 rpm to put enough energy into the flywheel to overcome compression


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## dcb (Dec 5, 2009)

electric_driver said:


> How much Nm do I need exactly ?


Why don't you stick a torque wrench on something and find out?!? Or at least get an approximation (worry about drag later).



electric_driver said:


> Ok, some calculations for the alternators then:
> 
> Power
> 1 Amp @ 48 V = 48 watt (0,048 kW) -speed is then about 2000 rpm-
> ...


Like I said in the other thread. Torque is directly related to motor amps, and rpm is directly related to motor volts. Note you can *probably* overamp a motor for more startup torque.

but I read the patent stuff and I have zero interest in explaining all the misconceptions in play here, especially since you don't seem to be listening. 

And that you wish to patent THE SIZE OF THE BATTERY IN PRIOR ART!?!? go screw your self for that actually.


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## electric_driver (Feb 4, 2017)

Ok, first for this post (which bugged me):



dcb said:


> And that you wish to patent THE SIZE OF THE BATTERY IN PRIOR ART!?!? go screw your self for that actually.


I didn't patent it for any financial rewards. Rather, I patented it out of ecological reasons. More precisely, it was an idea I had which I felt would be soon discovered by (commercial) companies and might be patented by them. Once patented, they could then even block the idea of being used by anyone.
So although I could have chosen not to patent the idea at all, that's not how things work and if I wouldn't have, it would (or could) have resulted in environmental damage.
I intent to make the idea available to as many commercial companies as possible, under my own terms (which aren't dictated by commerce but by ecology).
In any case, my patent would only affect companies, I don't intent to sue private people (hobby builders) that would use the system I patented.



dcb said:


> Why don't you stick a torque wrench on something and find out?!? Or at least get an approximation (worry about drag later).


I don't know the brand of the starter motor I have (which works to start the internal combustion motor). That said, it is powered by a Rocket 30-12 battery. That battery delivers 12 V and the amperage is:
under 13,8 V: unlimited amps
from 14,4 V and up: 7,5 Amps maximum



piotrsko said:


> Why cant you use the drive motor to start?


So you mean the electric motor ? This motor is connected to the wheels (drive shaft), and not to the internal combustion engine, so that won't work.



Duncan said:


> As to how much torque it will take to start your motor - remember the old days of starter handles?
> They would have a lever of maybe 9 inches and would take at least 100lbs force
> So 75 Ft lbs = about 114 Nm





piotrsko said:


> It has been my experience that you need 1 -2 hp for starter motors at about 100 rpm to put enough energy into the flywheel to overcome compression


So, I gather that the alternators do have enough power overall, but they just don't have the right gear ratio in order to have enough power to start the internal combustion engine.

There are 3 options I can see to overcome this:
- either use one of the alternators only as starter motor, and change the gear ratio of it.
- or buy a different starter motor that is capable of handling the high rpm and add that to the toothed belt assembly (by means of a disc with the correct gear ratio)
- or change the assembly so the starter motor can be disconnected, but using another way (using a clutch)

I prefer option #2 and #3 of these, since I didn't bought an internal combustion engine with 17-20 HP to then just use it at 30% or so of its power output, and also didn't buy an expensive alternator to then use it as a mere starter motor.

If I use option #2, what brands/models of starter motor exist that can handle this high an rpm ?
Also, the brand/model chosen would best be able to run on one of the battery packs I'll assemble (so the battery would supply 12 Volt @ 140A). The idea I have is to have the system select whichever of the 2 12V, 140A battery packs which is currently still fully charged (the battery packs are charged/used intermittently). The alternative is to use a standard battery (normally used with the starter motor) but the downside is that this battery would then not be recharged (unless the starter motor too can act as an alternator, but that would complicate matters, and probably isn't easy to get a hold of).

If a rectractible starter motor is really needed, how do I best set this up (can I combine gears with a toothed belt drive, ...) ?


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## dcb (Dec 5, 2009)

electric_driver said:


> i don't know the brand of the starter motor i have (which works to start the internal combustion motor).


why don't you put the torque wrench ON THE THING YOU ARE TRYING TO START?!?!?

Jesus f-ing christ..


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## electric_driver (Feb 4, 2017)

dcb said:


> why don't you put the torque wrench ON THE THING YOU ARE TRYING TO START?!?!?


I don't have a torque wrench to measure this.

In any case, I think I overlooked one other important thing: the alternators will be connected on the belt too, and the starter motor will hence drive them as well, so won't that increase the starting power requirements considerably ?

The alternators generate (together) 145 to 155 Amps @ 48V (at a speed of 4000 to 5500 rpm). The torque they generate is: 
Pout = torque (τ) * angular velocity (ω)
angular velocity (ω) = rpm * 2π / 60
angular velocity (ω) = rpm * 0,1046
angular velocity (ω) = 4000 * 0,1046
angular velocity (ω) = 418 rad/s
torque (τ) = rpm / ω
torque (τ) = 4000 / 418 rad per second
torque (τ)= 9,56 Nm @ 4000 rpm
At a speed of 5500 rpm, the torque is 9,56 Nm as well.

Rotation speed at starting should be way lower though (say 100 rpm), so needed torque will be 9,56 Nm for each alternator. There are 2 of these, so 19,12 Nm (per minute). In Nm/second that's 0,31 Nm/s. 0,31 Nm/s is about 0,0004 HP Adding that to the 2-3 HP needed to start the internal combustion engine makes 2,0004 to 3,0004 HP that's needed to start the whole thing. So, I'll need to buy a new (5 or 10 HP, 12V) starter motor anyway. The only problem I can see with this solution is that the batteries I'm using may either not be able to power it. A quick calculation seems to confirm this:
5 HP = 3728 watt
3728 watt/12 V= 310, 66 Amp
My batteries only provide 140 Amps, so I can't use these. I could buy a battery specific for this starter, but that battery then won't be able to be recharged.

For 10 HP:
10 HP = 7457 watt
7457 watt/12 V= 621,41 Amp

An alternative I was thinking about is just to keep the current (2-3 HP ?) starter motor and just put in a system that disconnects the alternators (electrically, not mechanically). I heard about such a system being used in recoil start generators, but I'm not sure how it needs to be done. I assume I need to put in a switch, but don't I need to built in the switch before the magnet, so unscrew the entire housing of the alternators for this ?
If this solution could be used, it might solve the battery amperage issue, since I assume it will be able to run on 124 Amp (if 2 HP is enough, if 3 HP is needed, it's too little -186 A-)

I've also been thinking to put in some sort of clutch between the starter motor and the internal combustion motor/alternators assembly. The idea is that I can then disconnect it after starting, avoiding unnecessary power loss. However, which kind of clutch do I best use for this. I'm thinking of having it connect directly to an axle, and have the alternators run on belts from this axle. The question here is: what type of clutch do I best use for this purpose. I prefer to use a cheap, and relatively lightweight type of clutch.


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## lastcyrol (Dec 12, 2015)

electric_driver said:


> The alternators generate 145 to 155 Amps @ 48V (at a speed of 4000 to 5500 rpm). The torque they generate is:
> Pout = τ * ω
> torque (ω) = rpm * 2π / 60
> torque (ω) = rpm * 0,1046
> ...


418Nm @ 4000rpm would give ~ 175kW
and 
575Nm @ 5500rpm would give ~ 331kW.

Obviously you take the relation between torque and angular velocity wrong.

My calculations give around 17.2Nm for a motor that consumes 150A from 48V, that would be if the alternator has the same efficiency as a motor as it has as a generator and that is 100%.


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## electric_driver (Feb 4, 2017)

lastcyrol said:


> 418Nm @ 4000rpm would give ~ 175kW
> and
> 575Nm @ 5500rpm would give ~ 331kW.
> Obviously you take the relation between torque and angular velocity wrong.
> My calculations give around 17.2Nm for a motor that consumes 150A from 48V, that would be if the alternator has the same efficiency as a motor as it has as a generator and that is 100%.


Yes. I made a mistake initially (I switched the torque for angular velocity, and forgot to calculate out the torque from this angular velocity number). I corrected it now in my previous post.

It doesn't really matter though; I'll either use my old starter motor, or buy a new one (that's some 15 HP in power -smaller ones aren't sold here much-). I'll use an AGM battery for it (that won't be recharged initially in the system).

If I buy a new starter motor, it will probably come equipped with a retractible system, and having examined this better, it seems it seems much easier to install than what I initially thought. So, I would then not need any clutch, nor integrate the electrical disconnect function on the alternators.
I'm assuming the AGM battery will be able to provide 930 Amps to it, so that's solved too.
And finally, the question I started off with: will running my alternator in reverse (so as a motor by putting a current on it) damage my alternators is solved too: I'll need to use a starter motor anyway, so whether or not this damages the alternator is of no concern in this project.

The only questions that remain are if I use my old starter motor:
I'll need some sort of clutch. I still don't know what type I best use, so could use some help with this. Also, I'll then need the some guidance on the electrical alternator disconnect method.


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## electro wrks (Mar 5, 2012)

I think we understand your conceptualizing and theorizing, but it seems you are woefully lacking in the knowledge and skills to actually design and build something based on your ideas. That's OK. This would be a difficult project for even the best designer/builder.

The good news is, if I understand your ideas and needs correctly, GM has already built this type of vehicle: the Volt( the *Holden Volt* in Australia and New Zealand, and with a different fascia as the *Vauxhall Ampera* in the United Kingdom and as the *Opel Ampera* in the rest of Europe.) A friend of mine has one, and he just loves it. He's careful to charge it whenever he has a chance, rarely buys gas, and yet can go on occasional long trips (using the gas engine) whenever he wants. The one drawback on long trips is that it's somewhat less efficient than conventional ICE cars because of the extra weight of EV hardware and batteries.

Volts are now available on the used market. If you really need to get your hands dirty, drive-trains and batteries are available at wreckers for Volt- based DIY conversions.


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## electric_driver (Feb 4, 2017)

electro wrks said:


> if I understand your ideas and needs correctly, GM has already built this type of vehicle: the Volt (the *Holden Volt* in Australia and New Zealand, and with a different fascia as the *Vauxhall Ampera* in the United Kingdom and as the *Opel Ampera* in the rest of Europe.)


I read the article about the GM Volt. It says that "the Volt operates as a pure battery electric vehicle until its battery capacity drops to a predetermined threshold from full charge. From there its internal combustion engine powers an electric generator to extend the vehicle's range as needed."

That's not at all how my system would work. With the GM Volt (and other cars using a same propulsion system), the battery capacity still needs to be substantial, given that people want to be able to reach most off their (nearby) destinations without needing to using the gasoline engine. The gasoline engine is only used whenever the user needs to go on a trip that is really far away (and can thus not be reached on the battery alone).

It is true that I also put in place a system that falls back on running the electric engine directly off the alternators spun by the internal combustion engine. However, this technique is meant only as a fail-safe. It would be used only when:
* (one of) the batteries break down
* or when the batteries installed have a too low C-rate to be able to be recharged fast enough by the alternators (the alternators hence generate more people than what the batteries can process)

The latter is the case in my demonstration vehicle (kart), simply because there are no batteries on the market that are both so small in capacity, and yet have such a high C-rate.

It goes without saying that in market-ready vehicles (no prototypes), the latter situation should never occur at all. As such, only the main system would be used. 

This main system would consist of one (or two) batteries that are constantly recharged by the internal combustion engine. The internal combustion engine is started/stopped depending on whether it needs to charge the battery (or batteries) or not. The internal combustion engine/alternators hereby produces a same amount of power than what can actually be processed by the battery (or batteries).

The idea is that the capacity of the batteries would not be more than the capacity needed to drive say 1 km. So, the batteries are used more like a buffer, and are implemented mainly to allow the vehicle to still obtain the energy consumption advantages the batteries bring.

As we read on the GM Volt FAQ, the battery capacity is with this vehicle still 35 miles (=56 km), so about 56x more capacity than what I intent it to be (and so has a battery cost and weight of the battery that is both 56x higher too). Besides that, -as mentioned-, the system works differently (it works either on the battery -EV mode-, or on the power of the internal combustion engine). My system works on both at the same time.


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## dcb (Dec 5, 2009)

my prius only goes about a mile on electric. It has a very small capacity battery by comparison, most hybrids do. This is not some new or even groundbreaking idea, and the Prius has had probably hundreds of thousands of development hours behind it to make it reasonably efficient. It has a motor/generator connected to the engine (that doubles as a starter) and one connected to the wheels.

Oh, and the batteries are augmented by the engine for higher power demands.

Oh, and IT IS STILL A GASOLINE POWERED VEHICLE!


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## electro wrks (Mar 5, 2012)

electric_driver said:


> I read the article about the GM Volt. It says that "the Volt operates as a pure battery electric vehicle until its battery capacity drops to a predetermined threshold from full charge. From there its internal combustion engine powers an electric generator to extend the vehicle's range as needed."


What you have conveniently left out of the quote from Wikipedia is the next line: " When the engine is running it may be periodically mechanically linked (by a clutch) to a planetary gear set, and hence the output drive axle, to improve energy efficiency"

So, YES the electric motor and the ICE CAN and DO run at the same time in the Volt. The designers at GM took a long time to work out the timing and sequencing of the electric motor and ICE to achieve maximum efficiency. It delayed the introduction of the Volt by many months, as I recall.


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## electric_driver (Feb 4, 2017)

electro wrks said:


> What you have conveniently left out of the quote from Wikipedia is the next line: " When the engine is running it may be periodically mechanically linked (by a clutch) to a planetary gear set, and hence the output drive axle, to improve energy efficiency"
> So, YES the electric motor and the ICE CAN and DO run at the same time in the Volt.


I looked into the GM Voltec powertrain and examined the details.
The system is still different, despite that electric motor and ICE can indeed run at the same time. The difference lies in the fact that my system (when in the "fail safe mode") just uses the electricity generated from the internal combustion engine's alternators to power the electric engine whereas the GM Volt either:
* mechanically links the internal combustion engine to the axle on which the wheels are mounted
* or use the internal combustion engine to generate electricity with so as to recharge the battery with this 
For that last one, it even does this only to keep the battery at the minimum charge level (30% of capacity). So it won't charge the battery fully (to 90 or 100%).



dcb said:


> my prius only goes about a mile on electric. It has a very small capacity battery by comparison, most hybrids do. This is not some new or even groundbreaking idea.


I looked into the Toyota Prius as well.
The Toyota Prius is a parallel hybrid, not a series hybrid (as my system).
I do read that it indeed has a very small capacity battery (which allows but 1 mile to be driven with it). Yet as its a parallel hybrid system, it works differently from my system. Lastly, I even doubt whether the battery can be recharged (about) as fast as it is discharged (operating the electric engine at normal speeds), given that it has a NiMH battery. That latter is what I refer to with my term "quickly rechargeable energy storage system".


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## dcb (Dec 5, 2009)

electric_driver said:


> The Toyota Prius is a parallel hybrid, not a series hybrid (as my system).


You don't know what you are talking about. It has a powersplit, at various times all the torque goes to the wheels, or to the generator, or both. from the generator it goes to the wheel motor and/or the battery. Why does it have a motor generator on the engine and one on the wheels if it couldn't series?!?!

You don't look very hard and you listen even worse, but you assert like you know what you are saying.



electric_driver said:


> Lastly, I even doubt whether the battery can be recharged (about) as fast as it is discharged


They use it to stop the car. I'd say it can be recharged pretty quick. According to these guys it EXACTLY can be recharged as fast as it is discharged (it is a low energy/high power form of nimh).
https://avt.inl.gov/sites/default/files/pdf/hev/batteryprius1052.pdf


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## electric_driver (Feb 4, 2017)

dcb said:


> You don't know what you are talking about. It has a powersplit, at various times all the torque goes to the wheels, or to the generator, or both. from the generator it goes to the wheel motor and/or the battery. Why does it have a motor generator on the engine and one on the wheels if it couldn't series?!?!


I never wanted to give the impression that I have any practical experience with electric cars or hybrid cars for that matter.

I just examined the HSD schematic over at wikipedia, and it seemed to me that there is a mechanical linkage between the ICE, and MG1 and MG2 (and both MG1 and MG2 can act as electric motor and alternator). The drivetrain explaination then mentioned that there are 2 hybrid modes (Eco and Power) so it can indeed run in series hybrid mode. That said, the internal combustion engine (ICE) still does have a mechanical linkage (it's not just electrically connected to MG2 -which acts as the main electrical motor I read-). So, if it is mechanically linked, who says the vehicle does not run only on the ICE at some points (say when the traction battery does get completely discharged, despite that it could -in theory- be recharged as fast as it is discharged ? 
I'm not fully convinced of the latter, and even if it never runs only on the ICE, I still think it differs from my system, just because I have no such mechanical linkage anywhere in my system.


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## electro wrks (Mar 5, 2012)

ed: You see initially GM had the Volt set up just as you describe your set-up with no mechanical link between the ICE and drive wheels. They quickly realized that in important driving situations such as hard acceleration, sustained freeway driving, low battery state, and others there was a distinct power and efficiency advantage to having a direct mechanical link between the ICE and the drive wheels. This is by itself or in combination with the electric motor/generators. The electric motors/generators and the ICE, through gear trains, clutches, and a lot of software, are set up accordingly.

As far as charging the batteries at a high rate and providing power to an electric motor at the drive wheels: there's no free lunch here. To do both and maintain normal driving abilities of the car (i.e. good acceleration and freeway speeds) you would have to have a more powerful, more gas guzzling ICE. This totally defeats the purpose of trying to increase efficiency and reduce gas consumption!

The Volt only partially recharges its battery from the ICE partly for this reason. Also, they do this because the cost of recharging the batteries from the ICE, if all the expenses are considered, is at least 5X the cost of recharging from the utility grid! They encourage you plug in whenever you can-to save money. The plug-in version of the Prius was also developed to take advantage of this cost savings

You're trying to reinvent the wheel here. To do it, you'll have to come up with a much better wheel!


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## dcb (Dec 5, 2009)

electric_driver said:


> I still think it differs from my system, just because I have no such mechanical linkage anywhere in my system.


I guess the problem is that "your system" isn't your system, the very first hybrids were people putting generators on their electric vehicles. It is literally the most simplistic way to make a "hybrid". But like a few people have tried to tell you, with all the conversion losses it is rather inefficient. Your focus seems to be on trying to put lipstick on that pig, because you invested a lot of time/money before really understanding it. Build a bridge and get over it.

the Prius allowed it to mix in parallel because it is more efficient than "pure" series all the time.

With all the conversion losses series is about the worst. It matters not if your engine is at peak bfsc if you lose %40 getting it to the wheels.

Besides the prius engine runs in atkinson mode (they increase the expansion ratio via valve timing), it is more load sensitive than rpm sensitive. And mg1/mg2 can do whatever they need to. You essentially get an "electric" continuously variable transmission w/overdrive. With a small battery to help accelerate and reclaim braking energy, and allow the engine to shut down completely when not needed (and also which provides instant 1000 rpm engine starts that reduce emissions, as apposed to a 2hp bump and chug start).










There was a team in the automotive x-prize that attempted a series hybrid, hoping to sync the motor and engine up magnetically, but it doesn't sound like it would work well except under very specific operating conditions. With power split (prius/volt) you get the best of both worlds. I would study the prius power split device first, volt would have gladly used it if it weren't for patent issues (AHEM!!), but they had to change it a bit to make it look different.

http://www.ucsusa.org/clean-vehicles/electric-vehicles/series-vs-parallel-drivetrains#.WKdHETsrKCg


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## electric_driver (Feb 4, 2017)

electro wrks said:


> You see initially GM had the Volt set up just as you describe your set-up with no mechanical link between the ICE and drive wheels. They quickly realized that in important driving situations such as hard acceleration, sustained freeway driving, low battery state, and others there was a distinct power and efficiency advantage to having a direct mechanical link between the ICE and the drive wheels.





dcb said:


> With all the conversion losses series is about the worst. It matters not if your engine is at peak bfsc if you lose %40 getting it to the wheels.





dcb said:


> like a few people have tried to tell you, with all the conversion losses it is rather inefficient. Your focus seems to be on trying to put lipstick on that pig, because you invested a lot of time/money before really understanding it. Build a bridge and get over it.


I hear both your comments on series hybrids, but still see value in a very simple (pure) series hybrid system. This as:
* it is simpler and cheaper to repair when broken down and replacement parts are easier to obtain (since they don't need to be very specific)
* it is much cheaper to make 
* they still offer energy consumption benefits over regular (non-hybrid) vehicles, especially when used in situations with a lot of traffick (a lot of starting/stopping) -they will be less efficient than parallell hybrids or complex hybrids like the Prius/GM Volt but that's a trade-off with the other benefits mentioned here-

I just want to try it out and see whether I can't make this work, and create a vehicle with the above benefits. If it won't work, I'll also accept this (the reason I'm doing this is to create environmental benefit, not to gain huge financial rewards). So if it doesn't provide that, I would just scrap the idea and focus on either changing the project or focusing on something else.



electro wrks said:


> As far as charging the batteries at a high rate and providing power to an electric motor at the drive wheels: there's no free lunch here. To do both and maintain normal driving abilities of the car (i.e. good acceleration and freeway speeds) you would have to have a more powerful, more gas guzzling ICE. This totally defeats the purpose of trying to increase efficiency and reduce gas consumption!


I'm not trying to: 
* charge the batteries (which aren't used right away)
* and drive the electric motor straight from the ICE

I'm trying to charge the batteries -which ARE used right away-
OR drive the electric motor straight from the ICE (= fail safe)

Also, increasing efficiency and reducing gas consumption isn't my only motivation on doing this. The point really is about making a propulsion system that makes road transportation more ecologic. That goes beyond just increasing efficiency and reducing energy consumption. For instance, if compared to a fossil-fuel powered (non hybrid) vehicle, my hybrid system is used whereby a biofuel is burned in the ICE, and the components of my hybrid system are easily recyclable -and there's very little or sometimes even no efficiency gain-, then I allready consider this an ecological merit, so a success. There are many other possible eco-gains that could come out from my project as well. I'll just keep tweaking things and look at the outcomes.

Anyway, there's little point in keeping to discuss the theory of my drivetrain; rather I need to build it, so it's better to skip ahead to my other post.


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## electro wrks (Mar 5, 2012)

OK ed, obviously your not going to be constrained by the laws of physics or any semblance of logic in pursuing your dream. That's OK. You have to admire your tenacity and thickheadedness. As you build your dream machine, please take plenty of photos and chart your progress towards your dream. If it works out, I'll be the first to acknowledge your accomplishment. Be aware though, in my career and life, I've seen the scum of the earth-some of the most despicable human beings- push the most unbelievable crap as the truth.

If it doesn't work out, please let us and the rest of the world know. Maybe it'll prevent some foolish person wasting our time and leading us down some twisted, dead end, logic rat hole.

Then again, it could get you elected president of the United States!


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## ICEICEbaybee (Jan 28, 2017)

I like your idea but why not move your starter motor in place of that alternator and be done with it?

You are being innovative. Nothing wrong with that. Let conventional individuals be just that. The trick will be to find a pulley the size of your flywheel to bolt on your crank to keep the correct ratio constant.


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## tinkeringgreg (Mar 27, 2008)

one thing i think you are overlooking is that you cant supply 12 volts to an alternator to make it run as a motor because of the rectifier diodes in the alternator. With that being said alternators can be run as a motor but you have to supply a three phase AC voltage directly to the stator while also supplying 12 DC to the field (rotor) you would also need to disconnect the alternator output cable while it is being used as a starter motor. I also doubt it will have enough torque to spin the engine


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## jared2009gregg (10 mo ago)

electric_driver said:


> Ok, first for this post (which bugged me):
> 
> 
> 
> ...


Simply put, if the electric motor is connected to the same drive axle as the combustion engine then it should be quite obvious on how to start this technology. Install a clutch system that would allow the drive sprocket of the combustion engine to freespin while throwing great amounts of battery power to electric motors, ( which will start the moving process), then release the clutch, (which will engage the combustion engine to turn over and crank), lastly once you have ignition on combustion engine drop all power to electric motors by means of a toggle switch and Viola you have everything that is needed to start and drive your hybrid. Also you can pull power off your magneto of the combustion engine to recharge your batteries for your electric motors. And yes an alternator would be a great motor for a hybrid cart. Good luck and safety first.


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