24v solar system, Adding a Turbine

[Jamie82]

Is it possible to add a turbine control to my system.

I have
1 classic 150 + wbjr
24v system
12 x 265w panels
12 x 6v Lead carbon Batteries 300Ah (900Ah)

I have a home made wind turbine and i have seen it output 10 amps. It could do more im sure.
I dont think that adding another classic and clipper would be worth it as it not very powerful

I have purchased 2 ssr from aliexpress 100a each ( i have not tested them yet )
I have also built a dump load that i can taylor a load.

I was hoping i could dump the current from the turbine and not the pv.

I am currently watching the votage and pulling it out of the wind and tiying it up if batteries are full.

Any help will be appreciated.

[dgd]

So is the output from the turbine 3 phase AC and you are rectifying it through a 3 phase bridge rectifier then seeing the 10 amps DC output?
If so then dumping the turbine load would be easy using a couple of SSRs to introduce three dump load resistors, shorted together at one end and the other ends connected to the AC turbine outputs.
You could use a 3 phase AC SSR such as a crydom D53PH25D or just two single Input AC SSRs
The classic could control the SSRs via AUX1.

Dgd

[Jamie82]

Hi dgd

Sorry I wasn't so clear on the output of the turbine was I
Its a 7 phase washing machine motor turbine and the rectifiers are on the turbine
(http://www.thebackshed.com/Windmill/articles/coglessFP.asp)

So i guess it would be in "diversion" mode and what would this do to the pv ?

Jamie

Oh we just moved from Auckland to Huntly

[dgd]

So the turbine makes 200 to 300 watts in a decent wind?
I would just connect it direct to the battery bank, not the Classic, with a breaker and couple of rectifier diodes so current cannot flow back out of battery to turbine or use another bridge rectifier.
The classic aux1 using float high could then just use a DC SSR to short the + and - through a wire wound resistor, Jaycar sell a 1.2ohm 1kW resistor for use with their Chinese 24v 500w turbine, it would be ideal for your turbine.

Dgd

[Vic]

Hi Jamie,  welcome to the Forum,

As an aside,  having nothing to do your plans for the Turbine ..

It seems that you may be planning on running that Classic very close to its maximum ratings.

If you are running four strings of three PVs,  using guesses for nominal PV ratings and de-rating factor for nominal power output from the PVs,  you will probably exceed the output current ratings for a single Classic on a 24 V battery system.

If you are planning on running six strings of two PVs,  it barely passes,  using the Classic String Sizer:
http://www.midnitesolar.com/sizingTool/displaySizing.php

You may already have run the Sizer for your PVs,  but,  generally,  it is not a good idea to run Power Electronics,  like Charge Controllers,  at or near maximums for hour-after-hour.

There can be some mitigating factors that might make your planned configuration better than the guess that I have made about your system.

FWIW,   Good Luck,  Vic

[Jamie82]

Thanks for both of your replys

They dont seem to have thoes resistors on their website anymore? Ill use my resistors i have made from stove elements
Will the Aux 1 use PWM to control float voltage?

I know I am running it close to the Maximum. Attached sizing tool.
I was planning on turning the current back a bit.
I just want the thing to charge on cloudy days.
I current only have 6 panels up and lll fit the rest when i get a chance.

Yes I will be running 4 strings of 3 panels

Do you recommend dialing the classic output say 86 amps? it says 91amps

[Vic]

Hi Jamie,  thanks for the reply,  and the Sizer data.

Yes,  would suggest that you Limit the Classic's output current to some reasonable value  -- perhaps 70-ish Amps.

You will want to use a large cable for the Classic output,  and a breaker sized to protect that cable.

One more thing;
You are running a 24 V battery,  with a fairly high String Vmp & Voc,  AND  at a fairly high current.  The ratio of String Vmp verses the battery voltage affects the efficiency of an MPPT CC.  The Classic would be more efficient,  and therefore run cooler,  if your battery were 48 volts,  rather than 24 V.

Your Classic would be more efficient it the String Vmp was  64-ish volts,  rather  the 96-ish (or whatever the exact values are).   Less efficiency means that the Classic will run hotter than if the lower string voltage was used.

You are running the Classic at a very high output current,  and charging batteries can require a number of hours at this high current,  if the batts were discharged very deeply.  This accumulated heavy duty-cycle can take its toll on the life of any kind of Power electronic device.

Furthermore,  when one Limits the CC current to a value  lower than the actual available maximum power value available from the PVs,  the string voltage rises,  somewhat.   This higher Vin makes any MPPT CC less efficient than it would be if  the PVs were fully-loaded.

If the environment where the CC is operating is warm or hot,  all of the above factors can add up to a HOT CC,  which is not a good thing,  IMO.

I,  too,  looked at running a single Classic 150 full up on a 48 V battery system,  using a String Vmp of about 93 volts,  and setting the output current Limit at about 75 Amps,  and finally decided that adding a second Classic was going to be a better solution,  and,  it has been a good decision (for me,  and the CCs).  We also Air Condition the Power room, to try to keep the batteries and power electronics as cool as possible ...  FWIW.

Hope that you can see your way clear to add a second Classic at some point in the future.  OR,  perhaps reconsider running strings of three PVs,  and choose strings of two PVs,  instead.   Know that this affects the size of your Combiner,  increases wiring length and losses,  and usually affects the PV racking as well.

BTW,  what do you expect the nominal temperatures to be in your Summer,  where the Classic will be operating?

These are my opinions,  based on some experience.   Good Luck,   Vic

[Jamie82]

It doesn't get too hot here in Waikato New Zealand id say max 35
I don't have an option to run different strings as i have 4 sheds each with 3 panels on them
they all come back to their individual breakers.
Thanks for your advice and ill see if money will allow to let me buy another classic.

Jamie