dynamic power analysis can be done in EPS, EPS documentation has a tutorial which explains the total tool flow. So I think it will be helpful for you.
Otherwise if you only need an approximation you can do it with RTL compiler, which is the synthesizer tool, It can read in the VCD, TCF and SAIF files and will report power according to the switiching activity. Just search for the comand read_TCF or similar in RTL compiler command reference.
Hope this helps.