Author Topic: HVDC VAWT Hybrid help needed  (Read 6301 times)

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stubbs

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HVDC VAWT Hybrid help needed
« on: March 30, 2016, 04:29:26 AM »
Hi,

I am facing a problem with my Wind Turbine.
It is a 3kW 3Ph 0-380VAC PMG VAWT.
The thing works in the present configuration.
But only when the Sun shines. lol

I have Solar Panels powering the lines in on the Inverter max. 220VDC. + Blocking Diode.
On the same Line the Rectified Voltage from VAWT.
The Inverter is a Wind Inverter PVI 3.0 OUTD-W. So no issues.

So when the Sun is up. I have a very low and efficient start-up.
The VAWT spins up and relives or adds to the load from the Solar side.
All good...

My "Problem"
When the Sun is gone. The VAWT has issues starting up, because of the initial Inverter start-up. Is about 50VDC @5% there of.

I would like to have Isolated the Turbines PMG. As well, a conditional Voltage sensing Contactor set at (or variable)
~75VDC or equivalent AC trigger point. An SSR 3 Ph Contactor would be superb. But how to control it from HVDC.

The Transformer idea would be the easiest. But the start and load Freq. is very low ~3-30Hz. So this kills the Tansformer idea???? or does it????

The DC idea is a dangerous. To step down from 200+ VDC safely is beyond my budget. Especially due to the wild Voltages /Transients.
A true investment risk; if you ask me.

I wish to control a 3Ph SSR Contactor with 24VDC at a cut-in voltage of (variable) ~75VDC or equivalent AC.
This will allow the Turbine to spin up, to supply the Power needed to power up the Inverter.
But at the moment, the Inverter cuts in too soon, to Power up; that is. The Inverter does not dump a load to the
Grid before ~160VDC.

Attached is a general Graphic of what I have. As well a Pic.
The other Graphic is the load curve that functions quite well. When the darn thing is already running.

Can you help me out. Or set me on the right track???

Thanks
Rob Brooks

Mary B

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Re: HVDC VAWT Hybrid help needed
« Reply #1 on: March 30, 2016, 04:33:31 PM »
Something like this to a contactor? Change the zener to a 75 volt range... other components might need tweaking also.


OperaHouse

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Re: HVDC VAWT Hybrid help needed
« Reply #2 on: March 30, 2016, 05:27:11 PM »
I've been following this on the other site and it seems that the controller should have a provision for this. Most electronic wall warts work fine on DC and they could be used to power a high side fet through an opto or relay.  If a software solution can not be found a micro like a UNO could monitor the voltage and slowly PWM up the voltage on the inverter, I do this with water heating.

margusten

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Re: HVDC VAWT Hybrid help needed
« Reply #3 on: March 31, 2016, 02:15:19 AM »
Hi stubbs,

I can see You put a VAWT on the ground.
There is no enough wind.
It must be on 20M tower.
I can see this problem.

Solar panels are big enough and working good.
I wish ,I had panels like this.

BR,

Margus

stubbs

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Re: HVDC VAWT Hybrid help needed
« Reply #4 on: March 31, 2016, 09:16:10 AM »
@Margus

Understand what you are saying. Being in a residential area on top of a hill covered with large Walnut Trees, and required building permitts.
Not happening. I have some pretty wild Winds. And nothing really to count on here; either. The Yearly Avg. here is ~4ms. Not too good.
If you look in the Photo towards the upper right. you'll see a HAWT that I built. I get an Avg. of 700W from a possable 1400W.
The VAWT was built from Junk. The only things I paid for was the PMG and associated electronics. The VAWT although at
ground level out performs the HAWT. As it is Magnetically levitated and weights ~190Kg.  Start up is around 2ms.
"When disconnected from the Inverter." Other wise a constant 6ms. That is why I am inquiring how to do this. 
The funny thing is, it started as an experiment 6 years ago, that went well. 

Thanks,
Rob

OperaHouse

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Re: HVDC VAWT Hybrid help needed
« Reply #5 on: March 31, 2016, 11:06:56 AM »
Perhaps a large bank of capacitors would help, more than 100,000uf.  This would give a longer time constant and allow the inverter control to respond.

Bruce S

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Re: HVDC VAWT Hybrid help needed
« Reply #6 on: March 31, 2016, 12:22:40 PM »
@stubbs;
Could you elaborate on Magnetically levitated . While most here understand the concept, there could be newbie who may not.
Thanks!
Point of Curiosity::: Where in Germany are you located about ?
I spent a good part of my late teens early 20s in Hanau.
Cheers
Bruce S
A kind word often goes unsaid BUT never goes unheard

stubbs

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Re: HVDC VAWT Hybrid help needed
« Reply #7 on: March 31, 2016, 07:16:37 PM »
Perhaps a large bank of capacitors would help, more than 100,000uf.  This would give a longer time constant and allow the inverter control to respond.

Interesting idea!!!! Try it in the morning...... lol

OperaHouse

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Re: HVDC VAWT Hybrid help needed
« Reply #8 on: March 31, 2016, 07:59:29 PM »
I think it has a chance of working, but I think the real issue is that you have an unloaded generator that is generating voltage and has no actual power.  The moment it is loaded the voltage drops dramatically.  I think a control like a UNO that would start to PWM a small load at about 6oV up to 75V and then start deceasing PWM over 75V.  The alternative is that at 75V and unloaded there just isn't any power at all to speak of.   Increasing that voltage to 90V or higher would guarantee that the wind is sufficient to get useful power. 

stubbs

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Re: HVDC VAWT Hybrid help needed
« Reply #9 on: March 31, 2016, 09:38:34 PM »
@OperaHouse

Understand what you are saying... An unloaded Genny is always a bad thing... lol
Just to clear things up... If I manually spinn the VAWT up to the given 75VDC and flip the beaker.
The Turbine does not slow down. The Inverter fires almost immediately. Remember ~190Kg is in motion.or not lol
The PMG is capable of 380VAC @100 RPM with a power of 3kW and 5kW @150 RPM. At low RPMs I have
pretty high voltage. And thus my problem. Your idea with the Caps is very fundamental. And am worried of
myself that I didn't think of it. see bridge circuit   attached

@Bruce S

I live near Bad Kissingen. Was stationed here. Got married up and built a House here.
Hanau I know pretty good. Have repaired a lot of Grove Cranes in the area.

I thank all for your support. I found part of the solution. Which was actually pretty cheap, and I feel like an idiot.
I have a Mean Well Led power supply. It is an electronic power supply. LPV-60-12 60W 12VDC out and variable 220AC in.
Well it has a DC in rating of 127-370DC. So I set up my 360VDC PSU and tested it. Guess what? CCCV starts @ ~32VDC
at a stable 12.17 voltage. I took it up to 360VDC and hooked my router to it. Drew about 170mA and was stable @ 12.17VDC.
And the darn thing is Isolated from the mains!!!! WOW!! I about pissed my shorts......... €26 was the cost 7 years ago.
Pics attached. I should be able to get a PWM/SCR setup running on this. Something similar to the Battery charge circuit that
I designed some time ago. attached
All BS aside... I will try adding a CAP per Leg in the morning. Makes sense.... see attached.

@Bruce S
You are correct. I should elaborate. I remember looking for information on this forever, and found nothing.
I will add some Photos tomorrow. In a new Post explain how and where to get, with Photos.

BR,
Rob
« Last Edit: March 31, 2016, 11:38:54 PM by stubbs »

stubbs

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Re: HVDC VAWT Hybrid help needed
« Reply #10 on: March 31, 2016, 09:50:25 PM »
Oooops.... Forgot two attachments in the uproar.....
So excited!!!
« Last Edit: March 31, 2016, 10:22:33 PM by stubbs »

stubbs

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Re: HVDC VAWT Hybrid help needed
« Reply #11 on: April 04, 2016, 04:59:04 PM »
The circuit worked!!! lol
You guys are going laugh you socks off!!!! ;D
Check out the following link. Corrected to england. Readable

http://export.rsdelivers.com/product/broyce-control/lmcvr-500v-24-230vac-dc/voltage-monitoring-relay-with-spdt-contacts-24-230-v-ac-dc/8505405.aspx?query=LMCVR-500V+24-230VAC%2fDC
« Last Edit: April 04, 2016, 05:23:34 PM by stubbs »

stubbs

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Re: HVDC VAWT Hybrid help needed
« Reply #12 on: April 04, 2016, 05:27:23 PM »