Wind turbine charge controller is not charging LiFePo4 Battery

atu

I am quite new in this forum and would appreciate, if you can share your thoughts and suggestions on my subject as explained below:

I installed an Off-Grid Solar, Wind and Battery connected parallel to each other. Solar panels(3.6kWp) are connected to Growatt SPF5000 ES off-grid inverter. The battery is also from Growatt (Hope 3.3L-C1) with 3300Wh capacity, LiFePO4 type, with BMS, communicates via CAN with the Solar Off-Grid Inverter. The Wind turbine (3.3kW at 14m/s / starts generating at 3m/s - as per datasheet) has its own Charge Controller with 48Vdc output and 5 kW dump load. 

The Battery, Wind Charge Controller and Off-Grid Solar Inverter DC outputs are connected in parallel to a 48Vdc busbar in a panelboard. But so far no loads have been connected to the system. Only the internal consumptions(draws 35VA in average) of the devices uses energy from either from solar, battery or both. 

I have been monitoring the behavior of the system for a few days through the monitoring system of the inverter and it seems that the Wind Turbine Charge Controller is not charging the Battery. In a normal day time, when the battery goes down to %95 SOC level, It is charged back again to %100 SOC with the Solar inverter. As the PV Modules are not generating energy at night, the level of the battery is going down to around %70 SOC level (due to internal loads). When the Solar Energy becomes available in the early morning, the battery starts being charged back to %100 SOC via solar Power. So there is no charging activity via wind turbine. 

At the same time, the voltage readings of the battery is so: 52.4Vdc @%70 SOC and 55.4Vdc @%100 SOC.

According to wind turbine manufacturer, the charge controller tracks the voltage of the battery, and cutoff charging when the battery voltage hits 56Vdc. But I have no idea, at which battery voltage level the charge controller starts charging the battery.

Btw; the turbine is rotating quite normal throughout the day and the AC voltage readings at the output of the turbine is around 30Vac(0..145Vac as per data sheet). However, there either no or very small ac current.

So, I am trying to find out, why the battery is not being charged via wind turbine charge controller. Could it be due to the battery voltage level, which I've read lowest 52.4Vdc so far? Should I allow battery to discharge even lower level like %45 SOC?

It might be hard for you to figure out system in detail, but incase you need further detail, I can share.   

Looking forward to hearing from you.
Thanks in advance.
Alp

clockmanfran

Details of your wind turbine, and its diameter please.

atu

Hi, attached find please the details of the turbine, inverter and the battery.

mike95490

30V from a windturdine is not going to charge a 48V battery.   You will need to see at least 55V from the wind before the battery starts to charge.   

clockmanfran

Hi, atu,

The figures you gave regards output are about correct, ie, 30vac and low amperage especially for a 2.4 meter diameter. 

It is a real problem in the domestic wind turbine market where the figures and numbers quoted by the manufacturers do not match the REAL outputs.

I have some of the best and most efficient domestic wind turbines in the world, designed by Hugh Piggott, been up for 14 years now, 3.7m diameter,12 footers, and are TRUE rated at 1kW , see http://scoraigwind.co.uk/all-of-the-books-by-hugh-how-to-get-them/   

   And yours at  2.4m diameter in a wind of over 7m/s, the best it could give about 700w.  But i suspect that your 2.4m wind turbine has its coils wound for the 7 m/s and not for slower speeds.

Now your figures quoted show its 3.3kW rated, but i suspect that is the destruction output in a true Hurricane wind speeds.   Yes mine have been in a Hurricane and survived, and at split second times have shown 3kW output before the automatic furling takes over.  

I now advice, and write in my books, that most NEW domestic wind turbines are not a cost efficient way of producing renewable energy. Each one of mine cost about $1000 in just the materials for a 1kW output, where PV, Photovoltaic panels, LONGI, cost New and the latest tech at about $470 for 1kW of panels. And modern Mono 120 cell are very good in low light conditions and give about 20% of rated output.
And best of all with PV on an array, there are no moving parts to service and balance the blades every year.

I keep mine flying and generating as its a very visible Renewable Energy statement.   But i now just install lots of PV and constantly warn folk to stay away from Wind Turbines.  Sorry to be the messenger of bad news.

For further real info have a look at this Australian forum on Wind turbines, as i post further details.  TheBackShed.com - Forum

atu

Thank you very much for your helpful remarks and comments.

I was on site to perform another real-time tests today. The turbine output voltage reached around 40Vac-42Vac and at the same time I saw current flow from 1A to 3A.

So you are right, it is unlikely, that the turbine will be able to meet ratings listed in product datasheet.

This is another expensive experiment for me:)

Best,