No, I do not believe there is centralised control of signalling in the manner you are thinking of. As far as I know switching of points and control of the flow on interlaced sections is all done locally.
For a good overview, the Czech Wikipedia page is worth a look - copy and paste "Tramvajová doprava v Praze" into Google and select the option to translate the Czech Wikipedia page into English. The enthusiast page listed 4th in the External Links is also worth a look, although again it will need translating.