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LiFePO4 and PMA Wind Generator

Adding a few relays isn't going to protect LiFePO4 batteries from the higher voltage created by a PMA. The Flooded batteries can handle the variable power of the PMA but the LiFePO4 needs a constant voltage input for charging.
That sounds like the statement from someone who wants to sell you a $400 device. What happened to the relay idea with the dump load?
 
I see two separate issues here.
1: BMS disconnect resulting in turbine overspeed and/or voltage spikes
2: Battery completely charged (low or zero current) resulting in overspeed.

If your dump load controller needs power to operate, just wire a modest sized lead battery in parallel so that it can buffer the supply in event number 1.

With regards to issue 2, LFP packs will taper rapidly to little or no charge current when full. To prevent turbine overspeed, couldn't you just have a dump load connected to the battery bus? It may effect your charge profile, but if the pack reaches the desired voltage, the load engages until the voltage drops below a certain threshold. That would ensure the turbine is always loaded. This control scheme would also work in the event that the BMS drops out, as the lead battery would rapidly exceed the voltage limit, and the dump load would be engaged.
 
Luthj - IMHO, that's a great solution. Simple, cheap and easy. The 12V will suffer if you're deep cycling your LFP battery, but who cares... it just needs to present voltage to the controller.

Regarding #2, that's how his existing controller works.
 
Here is the solution:

Get 2 x Schneider LC1D258 contactors with the appropriate coil voltage you are using. Then, bridge 3 of the 4 n/c contacts. On the opposite side of that bridge, add the turbine 3 phase wires . Then, tap the turbine 3 wires to 3 of the 4 n/o contacts next to the turbine wired side of the contactors. Then, connect the controller's 3 input wires (that would've came from the turbine before the contactorswere introduced) to the 3 of the 4 n/o contacts still available, on the side where the bridge is.

Now, connect your turbine controller directly to the lifepo4 bank. Then use the bms's normal output (which is protected by the bms), and power the 2 contactors on.

There you go.

Thus, if the bms is all good and no faults, the contactors stay on, turning the n/o contacts closed, and turning the n/c contacts open. Your turbine controller is charging the battery. If the bms opens its circuit, the load will switch off, thus the contactors will loose power. Thus the original n/c contacts which were open during power, will close due to contactors loosing coil power, and that will short the turbine. Your turbine controller is still connected to the battery, but cannot charge.

you can also apply the principle with solar. But not with those specific contactors, instead, just a basic 3phase contactor with 3 n/o. Using 2 of the 3 contacts, you can cut + and - pv input, without damaging your controller, because its still on, but cannot charge, of cause. The bonus is that you also have unused contacts as backup, when using the LC1D258 and normal say LC1D32 contactors respectively.

I hope this helps. I did not make a drawing, but will if need be.
 
I don't have anything to do with wind generation personally but the questions that have been asked on the forum that have prompted me to look at specifics, most of the wind controllers I've seen are lead acid specific and can not be reconfigured to be suitable for lithium. I'm sure there are types that can be of course.
mine say set the internal voltage trim to full on and rely on your charge controller...I think that would be ok for the newer batteries, if the controller parameters are set correctly. Some wind units require diversion loads, have you seen that?
 
Here is the solution:

Get 2 x Schneider LC1D258 contactors with the appropriate coil voltage you are using. Then, bridge 3 of the 4 n/c contacts. On the opposite side of that bridge, add the turbine 3 phase wires . Then, tap the turbine 3 wires to 3 of the 4 n/o contacts next to the turbine wired side of the contactors. Then, connect the controller's 3 input wires (that would've came from the turbine before the contactorswere introduced) to the 3 of the 4 n/o contacts still available, on the side where the bridge is.

Now, connect your turbine controller directly to the lifepo4 bank. Then use the bms's normal output (which is protected by the bms), and power the 2 contactors on.

There you go.

Thus, if the bms is all good and no faults, the contactors stay on, turning the n/o contacts closed, and turning the n/c contacts open. Your turbine controller is charging the battery. If the bms opens its circuit, the load will switch off, thus the contactors will loose power. Thus the original n/c contacts which were open during power, will close due to contactors loosing coil power, and that will short the turbine. Your turbine controller is still connected to the battery, but cannot charge.

you can also apply the principle with solar. But not with those specific contactors, instead, just a basic 3phase contactor with 3 n/o. Using 2 of the 3 contacts, you can cut + and - pv input, without damaging your controller, because its still on, but cannot charge, of cause. The bonus is that you also have unused contacts as backup, when using the LC1D258 and normal say LC1D32 contactors respectively.

I hope this helps. I did not make a drawing, but will if need be.
Wiring diagram would be awesome
 
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