windmill heat controller

[hallmgr]

Putte,

I have connected up three 50uF 250v capacitors to my heater and am running my windmill, I find it is spinning too fast.  Is it best to connect more capacitors in parallel to increase the uF rating or in series to increase the voltage rating?

Also I plan to connect another heater to the generator which would need another set of capacitors.  What overall effect will having two heaters instead of one in the system?

Hallmgr.

[Putte]

Hi Hallmgr.

It sounds like you need more 'uf' then (parallel) but what was your volt/hz and amp and did you get some heat?

You mean two system at the same time? if so you need two setups i havent tried that but it seams that i would work. I do hope that you can get it to work it very simple ones it get going.

Putte.

[hallmgr]

Putte,

The windmill was over speeding, giving a voltage was reaching 200v but the current was only 1-2 amps.  I would need the current to rise to about 4-5 amps to keep the windmill speed down.  The windspeed was around force 4-5.

I have three 50uF 500v capacitors connected to each heater.  Both heaters got hot when it was running.

Hallmgr.

[hallmgr]

Putte,

I was wondering, if I start to load my windmill at around 20hz at what frequency could I expect to have full load?  I would need to be able to bring full load onto the generator without too much increase in speed.

Hallmgr.

[Putte]

Hello Hallmgr.

I think you can load it to the limit were it would have trouble get going in some 3 m/s. It seams that you have a bit lower volt than i have done my experimenting in. I think it will work the draw back would be more expensive do to more 'uf' needed.

I hope i have leaded you in a good way and that you can get it to work. There is some parameters to work with volt/amp/hz/capacitors/resistors but when it all working in harmony it is very simple.

Putte.

[hallmgr]

Putte,

You mention resistors, where do they come into it?

Hallmgr.

[Putte]

The "resistor" i meant the heating element.

Putte.

[hallmgr]

Putte,

I now have capacitor values of 170uF, 250v per phase on one heater and 120uF, 250v on the other but i do not see much difference, the windmill still overspeeds in moderate winds.  I am using a mixture of different sise capacitors on each heater,  do they all have to be the same values or does it not matter?

Hallmgr.

[Putte]

Hallmgr.

Thats a disappointment and your volt will not go up? I was thinking if you try with a smaller load=higher ohm so if your volt goes up so will the load and braking the genny. I did think this system would work for you but it maybe that your volt is to low. My genny was working up to 450 volt and down to some 300 volt with more 'uf'. Are you getting some good heat?

I have not done any experimenting with to system to one genny.It sounds like it would work.

Have you tried it to one system and seen any better results?

Putte.

[hallmgr]

Putte,

My voltage goes up to around 200v in moderate wind, the voltage should only go that high in a gale.  Normal working voltage is around 100v.

I do get good heat but the voltage rises to much and the current stays very low.

Would it work to put in a small transformer to increase the output voltage?

I may be able to increase the voltage by altering the stator in my alternator.  I have three coils for each phase, each coil has one connection to the star point and another to the output, so basically the three coils on each phase are in parallel.  If I were to alter the wiring so that the three coils in each phase are in series in stead of parallel then i might get around 300v phase to phase, would this work?

In the meantime I will try with just one system on the generator and see what difference it makes.

[Putte]

Hallmgr.

Thats a good idea to change the coils for higher voltage. What i have seen is high volt and low amp but that means low losses from the genny and more power to the heating element. I guess you need to change the connecting on the element or maby its possible to connect your systems in series one feeding the next.

I have used amp and the volt across one resistor (element)to metering the power volt*amp*3=Watt. I think this is close to the real power.

It would be fun if you got it to work :-)

Putte.

[hallmgr]

Putte,

I have tried disconnecting one system from the generator and running it, the windmill run out of control and I stopped it quickly, so having two sytems seem to work ok.

I have an ammeter in series on one phase and a voltmeter between the other two phases to measure my power, same way as you mentioned.

I will now look at re wiring the alternator to give a higher voltage, this will not be easy as the stator is encased in fibreglass resin but I have a rough idea where the connections are.  

I will let you know how I get on.

will it be ok to put the higher voltage straight onto the elements?

Hallmgr.

[Putte]

Hallmgr.

I did put my voltmeter were the (one) heating elemnt start and then ends that mening reading the volt over the element.

If you put your elemnt in series and the are the same you can have the dubble voltage.

I hope it goes well with the re wiering.

Putte.

[hallmgr]

Putte,

I have looked at re wiring my stator and it will probably be a complicated job, probably easier to make a new stator.  I have added some more capacitance to the system and it seems to works ok so I think i will leave it for now.

I notice now that the generator takes a bit of wind to get it going, it only turns slowly in light winds.  Would there be a way to vary the capacitance of the system so it would turn faster in light winds?  I know the wimdmill would only produce a couple of hundred watts or so in light winds but this is enough to keep a little warmth in the heaters, so when the wind increases the heaters start to give off heat.

Hallmgr.

[kajs]

does this mean 50Hz=full resistor load  with 50Hz capacitors?