Removing FileVault2 key from memory on lid close

I would like to know, how to remove FileVault2 keys from memory, when I close the lid on my Macbook pro 15" running Yosemite.

It works, when I leave the computer as it slowly goes into standby by itself (first lock-screen then the screensaver and then standby). I had manage to do this, with this classic command:

sudo pmset -a destroyfvkeyonstandby 1

But the problem is, that when I close the lid when the screen is just locked, or it isn't locked it, wouldn't destroy the keys. It just locks the screen.

Short version: I want to destroy FileVault2 keys when I close the laptop lid.