Help,model disappears when get close

[clkgtr]

Hi,
I made a station canopy model and exported to the game.When I get close ,it will disappear because the origin of the model is out of FOV.But there many big stations in the original game,and they never have this problem.Why this happen to my model.
The DEV docs said don't attach the elements to one shape,but this will not solve the problem perfectly.Element still disappears instead of the whole shape.
Could anyone give me some tips? Thanks

This pic looks fine when far away to see the station canopy.

The capony in front of the camera already disappeared