2kW grid tied

[energytech]

Dear all,

Does anyone have any experience with grid connecting a Navirton 2kW with an SMA inverter in a windy spot. I am happy that the controller that comes with the turbine will act as a rectifier but there are a few problems i can see arising. I do not have an electronics background so will not be able to work this out alone.

If in a very windy spot, the turbine produces more than the maximum input voltage of the Windy Boy, then damage can occur to the inverter. Also, if the grid goes down, the inverter will be switched off, and the extra power needs to be diverted to a dump load rather than having the turbine running out of controll. A controller of sort will be needed to divert the over voltage when to windy, and all the power in a power cut. Is a controller of this sort available? Are these problems ones that people testing are facing and if so are there ways around them?

I would like to connect the 2kW to the grid but understandably do not want to damage the very expensive windy boy.

Any advice would be much aprechiated.

Olly

[westcott]

Hi,

I think the link http://www.navitron.org.uk/grid-tie.htm answers your question.
The highest voltage they saw was 375.

On a related note, the SMA WB2500 has a max power of 2500 (oddly enough), but the 2KW tirbine maxes at 2600W (at 15m/s).

Would this be OK in practice?

Where to get the best deal on an SMA WB2500 ?

Hamish

[Ivan]

The main area for concern would be if the power lines failed in windy conditions (in some areas, they fail predictably when winds are strong). This is the worst case scenario - no power consumed by the GT inverter, and high power available from the wind. From my experimentation, the maximum voltage we saw was well under the 600v maximum that the SMA inverter can take. The controller, will actually dump the excess power to heater elements in these conditions, but we recommend that a relay is fitted to divert power to dump loads (eg immersion element) if the voltage exceeds say 380v. This would provide adequate protection for the turbine - which does not like free-wheeling with no load in high winds (it causes over-speed, which can result in blade damage etc)


Ivan