Génératrice

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Présentation

Cette page technique couvre le générateur DC de 5 kw que j'installais au besoin dans la boite de ma camionnette Chev. S10 électrique ce qui me procurait une autonomie de 80 à 200 km maximum.

Ce générateur est simple, efficace et conçu à partir de pièces facilement disponible . Après 28 heures de marche et 1700 km d'utilisation, mon seul commentaire...c'est un générateur de premier choix pour assister les batteries d'un véhicule électriques sur route. ( mise à jour 2013, ce générateur a été utilisé pendant plus de 10 ans, de 2006 à 2011, il fonctionnait au quotidien sur autoroute avec l'autre VÉ GM Cavalier)

Merci à Jérôme Breton de St-Lambert qui m'a soufflé l'idée d'expérimenter à partir d'un moteur à induction triphasé...



Le moteur à induction triphasé (générateur)utilisé est de type ouvert ventilé, la description est la suivante: BALDOR, 7.5 HP, 208-230/460 volts, 19-18/9 amp, RPM 3450. Les connections internes modifiés de étoile à Delta nous donnent de nouvelles caractéristiques soit ; 138 volts et 31 amp.





HONDA 11 HP, GX340K1QAE


Ce générateur est conçu en couplant un moteur électrique triphasé ( utilisé comme générateur ) à un moteur à combustion interne de la dernière génération . Ces moteurs à combustions consomment 25% moins d'essence, sont moins bruyants, plus léger et un peu moins polluants. Le choix s'est arrêté sur un Honda 11 HP, ces moteurs respectent la réglementation californienne CARB en therme de diminution des émanations.

Le moteur Honda 11 HP consomme 3,4 litres/hr à 4500 watts de sortie DC du générateur. Bien qu'il tourne à 3600 rpm, la puissance utilisé est moindre que la puissance maximum ( probablement 8 à 9 Hp ) de manière à respecter le courant nominal de 31 ampères du générateur.



Les résultats

Ce générateur est utilisé pour les parcours de plus de 50 km.

Aucun relais, interrupteur ou circuit électronique n'est nécessaire. On démarre le moteur à combustion, on monte le régime à 3600 RPM et en moins de 2 secondes, le générateur fourni un courant de 30 ampères. En fait, il s'agit de 31 amp. à 144 volts lorsque le véhicule roule, 30 amp. à 155 volts lors d'un arrêt du véhicule ou encore 32 à 33 amp. avec 132 à 136 volts lors des accélérations. Nous obtenons donc une puissance de 4500 watts en continu.

Le voltage DC de sortie du générateur est tout simplement un voltage variable, au même niveau que celui des batteries, sans changement important de la puissance alors que les batteries du VÉ varient en tension d'un arrêt à une accélération.

Si on désire diminué la "pollution sonore" lorsqu'on traverse un village ou une ville, il suffit de diminuer le régime ou arrêter le moteur via un contrôle de puissance ou un interrupteur et de remettre plein régime à la sortie de la zone urbaine.

L'autonomie de mon VÉ à batteries seulement est de 50 à 90 km. L'utilisation du générateur me permet d'obtenir 80 à 200 km. maximum.


Important

ATTENTION, HAUT VOLTAGE

200 VDC ou 150 VAC 3 phase


ATTENTION, SURCHARGE

Le générateur endommagera les batteries si utilisé en fin de charge. 30 amp. à 200 volts sont possible


Mise à jour 2013, merci à Paul Ring de New Harbor, Maine pour ces deux illustrations des connections moteurs, condensateurs et pont de diodes.

Ces questions et son travail facilitent la compréhension de cette installation avec laquelle de nombreux "débrouillards" continue d'expérimenter depuis des années.






Following is a copy of an email from Paul Ring to me.

Alain,
Thank you for your drawing,Your drawing is a good reference for this purpose.
Paul, 
How is the motor grounded to the truck body?Did you run a ground wire to the generator control box? Does this box get hot?

Alain,
Your battery power pack is not  + or -- connected to the body and we don't really want to ground the generator to the body also. It is like a transformer, we want it to be isolated. The rubber support between the generator and the truck or car will allow an isolation if a cable or defect part in the box come in contact with some steel box or the generator. This is why I am using PVC box. No, capacitor box does'nt heat at all.
But the bridge does heat. You need an heat sink on this device.

PAul,
What is the material in between the capacitors?
Alain,
Cardboard or  plastic, it's a mecanical issue to prevent the capacitor to wear by contact on each other with vibration.

Paul,
Do you have RECOMMENDATIONS for components?:

9 running capacitors 50uf 330 volts 
http://www.electricmotorwholesale.com/BALDOR-OC3050F09/
OR
http://compare.ebay.com/like/260868394140?var=lv&ltyp=AllFixedPriceItemTypes&var=sbar
~
Alain,
I did pay some 14$, not 45$. Yes, these are the right parts but check for the size, same job but you can have same capacity with the size being double (size of capacitor box concern)
The major concern is to install RUN capacitor, not START capacitor. It's the difference between fire and no fire.

PAul,
3 phase bridge rectifier
Did you use an 80 amp rectifier with heat sink?
http://www.windynation.com/products/accessories/conversion/rectifiers/80-amp-3-phase-bridge-rectifier
Alain,
Very nice unit !!! Bridge, heat sink and price. GO for it !!!

8 x 8 x 4 PVC box
http://www.gandssupply.com/product.asp?itemid=356&gclid=CObHu4iLgLgCFcSj4AodfQsASg
May be you should received your stock, make the wiring and test and complete final instalation after. There is a possibility where you could had 10 or 20 uF of capacitor to reduce the motor RPM. There was not much room on the small box a use for the connection to the bridge...

1-inch flexible motor/generator coupling:
https://www.surpluscenter.com/item.asp?item=1-3422-M&catname=powerTrans
https://www.surpluscenter.com/item.asp?catname=powerTrans&item=1-3422-X
~
Yes, you have the picture of the unit in the truck where the unit is installed on a steel base. While it was in the car, I had the electric motor modified with a C Flange. I had an adapter/spacer built between generator and the baldor and there was no frame and base. The complete unit is very long because of the two shaft one against the other one. I did cut a part of the Baldor generator shaft.

Would you recommend the use of an Electric Motor Adjustable Slide Base?
http://www.ebay.com/itm/New-Electric-Motor-Adjustable-Slide-Base-56-Frame-/271015839136?pt=LH_DefaultDomain_0&hash=item3f19cd85a0
~

Alain,
I didn't. I use spacer for the height and hole diameter a litle bit bigger for aligment.
For testing purpose, the best load to use is your battery pack with bridge rectifier. If you use a resistor load on AC side, you need to connect the load only at high RPM when voltage output is present and disconnect the load before lowering the RPM. This generator won'y initiate voltage output if it see a load... With a battery pack, everything is easy because it will see a load only after the voltage rise at battery pack level.

You can run test your generator without a load but "take care", voltage will get verry high near the 300 vac level...

First time, if there is no voltage at the output, it is because there is no  initial magnetisme in the rotor. You lose it if generator is stopped with a load on AC side...
Working with a battery pack as a load, you will have to do the following only one time and no more for years...

With the motor stopped, using a 6 or 12 vdc battery with 30 amp fuse, you connect it for 2 seconds on any set of two wire of one of the 3 phase. This will make a induce a magnetisme on the rotor and you are ready to make power with it.
Regards

Références

La suite de cette page est constitué d'extrait de courriers électroniques principalement de mes correspondants EVDL (Electric vehicule discussion list) en rapport avec l'élaboration de ce générateur à partir d'un moteur à induction triphasé. Merci à Jérôme Breton à qui je dois de m'avoir "souffler" l'idée d'utiliser un moteur à induction 208 volts triphasé à haute révolution.. Ces moteurs sont peu dispendieux, disponible, léger, ils sont rarement utilisé comme générateur, je commenterai davantage suite aux essais.

MERCI À TOUS MES CORRESPONDANTS !



< Jérôme Breton > Tu pourrais aussi prendre un moteur électrique 208 volts trois phases bobiné pour rotation a 3600 rpm

< Alain St-Yves > I am actually working on a DC generator project as an occasionnal range extender or charger if required. I understand I should use a DC motor or an high efficiency alternator but I happen to have a 208 Volts , 3 phase induction motor , 3450 RPM and I am trying to find why those low cost motor are not used as DC generator (with a bridge rectifier ).

Does it have to be started as a motor with a 3 phase power grid before being able to be used as a generator with an ICE ???

Motor specifications are High efficiency Baldor, HP 7.5, 208-230/480, amps 19-18/9, RPM 3450

< Peter Vandewall > Contact the folks at Homepower http://www.homepower.com Issue #71 June/July '99 had a really good article on using induction motors as generators in Micro-hydro setups. You don't need any AC in order to start it, there should be enough residual magnetism to start it off, if not you can charge the coils by briefly connecting a 9V battery

< Lee Hart > I have never had any luck with any residual magnetism in an induction motor. The AC power pretty effectively insures that it is thoroughly demagnetised. But, they have always started generating with as little as 9 volts DC of initial charge on the capacitors.

The behavior of an induction generator is analogous to an induction motor. Frequency and voltage are both directly proportional to speed.
For example:

run as a motor: 3450 rpm at 60 hz, 120 vac
2850 rpm at 50 hz, 100 vac
synchronous speed: 3600 rpm at 60 hz
3000 rpm at 50 hz
run as a generator: 3750 rpm at 60 hz, 120 vac
3150 rpm at 50 hz, 100 vac

As a generator, the slip goes in the opposite direction (runs above synchronous speed). The no-load voltage is proportional to rpm. As a
motor, you are actually applying a slightly higher voltage to overcome back emf; as a generator, a load slightly decreases the voltage.

A high performance induction motor has very low slip; speed barely changes from no-load to full-load. As a generator, such a motor has good
voltage and frequency regulation (driving it at fixed rpm produces almost a fixed frequency and voltage regardless of load).

A cheap induction motor has poor speed regulation; its speed falls dramatically under load. As a generator, such a motor's voltage and
frequency will thus also sag dramatically under load.

< Peter Vanderwall > He states that you will loose residual magnetism if: the generator is rapidly shut down with load connected, looses excitation because of an overload or if you let it run down(blocked intake) with a load attached.

< Rod Hower > I worked at Baldor for 4 years and I am familiar with their motor construction. I don't believe they make compound motors anymore, but the motor described below is a 2-pole (3450 Rpm instead of 1800 rpm at 60 Hz). It has class H insulation and most likely Phelps Dodge spike resistant windings. I have run their motors at 120% overload until the grey paint turned brownish due to heat. The motor still worked fine.

< Richard Lane > You will also need to calculate the right size capacitor. There is a small book out referencing IMAG's with good case examples. It is called Motors as Generators for Microhydro by Nigel Smith

< Rod Hower > Your better off adjusting the speed of the AC induction motor to get the desired voltage and use a full 3-phase bridge on the output to rectify the 3-phase from the motor. The output voltage will vary with the speed of the motor, load and slip.

< Lee Hart > 3450 rpm is normal slip, which means it is not a high efficiency motor (except in the minds of marketing). 3500 rpm would be low slip, i.e. high efficiency.

> < Alain > how I will be able to bring the voltage down from 208 AC 3 phase (or 230) to somewhere around 126 to 155 VDC. If I bring down the RPM from 3450 to 2500, I could have a lower voltage and power but what about a 43 HZ AC sinewave ???

> < Alain > Also, there are nine wires in the junction box because of the 208-230/480 voltage possibility.

9 wires? There aren't enough wires to have separate taps for 208v; they must have only provided for 230v or 460v operation. Can you figure them
out with an ohmmeter? There are too many posibilities. Here are just two.

- 3 wires for a Y-connected 230v, 3 more separate 230v windings which can be connected either in series with the first Y, or in a parallel Y
- 3 center-tapped windings, which you can connect in Y or delta, but only 1/2 the winding is used at 230v.

A proper 240/480v 3-phase motor would have 12 wires; 3 phases of 4 wires for each pair of 240v windings. In this case, you can connect the phases in series or parallel, and in Y or delta. Delta lowers the voltage by 1.7 but raises the current by 1.7. 230v Y becomes 133v delta, which is
just about right for charging 144v batteries.

< Rod Hower > Most Baldor motors are Y connected and they only bring out the wires to series/parallel for 240/480 (9-wires).
They are pretty standard on there connections

1
coil A1
4
7
coil A2
Y connection
Coil B2 Coil C2
9 8
6 5
coil B1 coil C1
3 2

So for low voltage you would have 4, 5 and 6 tied together and the following pairs 7-1, 8-2 & 9-3

For high voltage you would tie together 4-7, 5-8, 6-9 and 1,2,3 connect to 3 phase source.

< Lee Hart > A large AC capacitor in series with the AC input to your bridge rectifier. For a 3-phase setup, there would be 3 of these capacitors;
one in series with each phase.

Running as an induction generator, the same winding current rating applies (it's limited by wire size). So this is the most current you can
get out of it. Likewise, we'll assume the same output voltage. Then the power you can get out of it is 240v x 18a = 4320va per phase. But it has
to run at a capacitive power factor; say it's 0.8pf. Then real power output per phase is 4320va x 0.8pf = 3456 watts. Multiply by 2 for all 3
phases, and total power output is 3456 x 2 = 6912 watts.

How much battery charging current will this produce? You'd have to know the voltage output and efficiency of the charger; use 80% and 150vdc as
typical numbers. So 6912w x 0.8eff = 5530 watts of DC. 5530w / 150vdc = 37 amps.

If your generator is actually delivering 240vac, its peak voltage is 240v x 1.414 = 340v. If you want to charge a 150vdc battery, you have
340v - 150v = 190v difference to get rid of. If you use a series capacitor to get rid of all of it, your power factor will only be about 0.5. That's fine as far as the induction generator is concerned, but you'll only get about half the DC charging power that the generator is capable of delivering.

> < Alain > The set up is as next, LOW VOLTAGE, 3 phase to 3 following set (9-3), (8-2), (7-1) and wires (6-5-4) are twisted together
> HIGH VOLTAGE, 3 phase to (3), (2), (1), and following sets twisted (6-9), (5-8),(4-7)

OK, so it is as someone (Rob Hower?) just posted. Graphically, the connections are (set display font to fixed width):

high voltage connection low voltage connection

phase 3 phase 2 phase 3___.________
\ / | __|_______.___phase 2
\ / | | | |
6 5 | | 3 2
9 8 9 8 \ /
\ / \ / \ /
\*/ <--hidden \ / 6 5
| connection | 4
| | |
7 7 |
4 phase 1____|_________1
|
|
phase 1

Both of these are Y configuration. If you can find and disconnect the "hidden connection", you could reconnect the windings in delta configuration. This has the effect of lowering the phase voltage by sqrt(3), and increasing the phase current by squrt(3). With the pairs in parallel, 240 vac at 18 amps becomes 138 vac at 31 amps. The peak of 138vac is 195v, so to charge at 150vdc, you only have to get rid of 195-150=45 volts.

phase 3_____
| \
| 3 9
| \ \
| \ \
4 * 6 *
| | \___phase 2
| | /
1 7 2 8
| / /
| / /
| 5 *
phase 1__|__/

< Lee Hart > Alain St-Yves wrote:
> I am actually set with a 10 HP variable speed DC motor coupled to the 3 phase induction motor ( as generator, a 7.5 HP Baldor at 3450 rpm ).
> should I need capacitors between phases when used as a generator?

Yes! It will not generate unless it sees a capacitive load. If the load itself is not capacitive (and very few are), then you have to connect a large AC-rated capacitor across each phase.

For your motor, they will be BIG -- like 20-100 microfarads for a resistive load, even more if the load is inductive (like a motor or transformer).

The motor may have enough residual magnetism to start generating automatically with just the capacitors connected (but no other load).
However, my experience is that it is better to pre-charge the capacitors with some small DC voltage.

1. Disconnect all loads from the induction generator.
2. Start spinning the induction generator (its voltage will be zero).
3. Charge the capacitors to some DC voltage (a 9v battery is enough).
4. Switch the charged capacitors to the generator output (it will start
generating AC, at a voltage and frequency proportional to rpm).
5. Now, switch the load to the induction generator.
6. If you have enough capacitance so the total load still has a
capacitive power factor of 0.8 or so, it will keep generating.
7. If the load is excessive, or not capacitive, the induction generator
output will suddenly collapse to zero volts; you have to start over.

< Alain St-Yves, 25 dec.2001> Comments about this previous email; As the load is a battery pack, no problem about residual magnetism or colapsing has been seen since it is out of the test bench last april. A 12 volts battery had been used for one second on one phase while the motor is stopped to make an initial magnetism.. That was the way to go after many weeks of testing, asking, experimenting...

Another unit has been built for the EV Mazda Pickup of Jean-Claude Pépin. A Hyundai, 230/460 V, close, 7.5 HP, 3600 RPM has been used. Same results have been obtained with a set-up of 150 uf at 3600 rpm. I have never initialized the magnetism, it did worked first time by itself.

Another unit is on the test bench. This time for fun... it's a 1735 rpm, Hawker Siddely Electric Motor, 7.5 HP, close.

Have fun... take care, WARNING, HIGH VOLTAGE
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