Windmill grounding system
Windmill grounding system
(OP)
Hello expert,
I'm working on a windfarm project. We are at the stage of designing the grounding system of the windmill. Each windmill has a concrete foundation with rebar.
Assuming that
-windturbine requires a fairly low resistivity ground system
-type of soil we are working with is mostly fragmentary rock.The resistivity of that type of rock is in general pretty high.
-concrete has the ability of retainning moisture
-foundation of a windturbine requires a lot of rebar
Considering the fragmentary rock, is it more efficient to
-use the rebar (as UFER states) only for the grounding system
-build a bare copper ground system in the soil on the top and around the foundation with ground rod
-build a bare copper ground system around the base but inside the concrete foundation
I can't attach a drawing if you have question.
thanks in advance
Mafle
I'm working on a windfarm project. We are at the stage of designing the grounding system of the windmill. Each windmill has a concrete foundation with rebar.
Assuming that
-windturbine requires a fairly low resistivity ground system
-type of soil we are working with is mostly fragmentary rock.The resistivity of that type of rock is in general pretty high.
-concrete has the ability of retainning moisture
-foundation of a windturbine requires a lot of rebar
Considering the fragmentary rock, is it more efficient to
-use the rebar (as UFER states) only for the grounding system
-build a bare copper ground system in the soil on the top and around the foundation with ground rod
-build a bare copper ground system around the base but inside the concrete foundation
I can't attach a drawing if you have question.
thanks in advance
Mafle






RE: Windmill grounding system
RE: Windmill grounding system
I would expect lightning to be a major problem with windmills. The effectiveness of the grounding system for lightning depends on the high frequency impedance of the system. A system of radials from the ground loop around the tower might be considered.
I haven't seen anything written in particular about protecting windmills from lightning (I haven't done any searches either). How would you protect the turbine from lightning that strikes the blades? Is there a mechanism to shunt the surge around the turbine to the tower?
RE: Windmill grounding system
Mafle, I recommend you get hold of the Wind Energy Handbook by Burton, Sharpe, Jenkins and Bossanyi published by Wiley. ISBN 0 471 48997 2, which provides very useful reference material on all aspects of windfarms.
Regards
Marmite
RE: Windmill grounding system
Alehman, as for now I've worked with two manufacturer, GE and Enercon and both of them has a completely different design. The grounding system of Enercon is base on ufer. Rings fo bare copper are laid in the concrete and one ring is outside of the concrete. They are all connected. There are no driven ground rod.
GE use partly ufer. they recommend one ring of bare copper inside the concrete and one in the soil on top of it. Ground rod are connected to the outside ring.
As we are building the windfarm on top of mountains and the rain are easely drained, I think that using the concrete is our best bet connected to the rebar as well as driven ground rod. The thing is not to overdesign but to be sure that the design will be a safe one.
RE: Windmill grounding system