Nice three pronged plug for WS2811 LED strips?
Since I also have worked on the same type of displays, I must say that you are in the right direction.

But the thing is, connectors highly depend on the type of wires that are connected to both led strip and connector. Your wire must have enough gauge rating wire so that it would support such huge current. Here you can find what type of wires to use for your current consumption.

Once you select the kind of wire to use, the connectors can be chosen appropriately. This kind of connectors are simply ideal for situation. But I ended up using this type of connectors. 

I must add that I have added the links to ebay. This does not mean that you must buy from it. I used that site just for the sake of pictures. Those kind of connectors are simply enough.