Could not find rtl_work.TB.vhd

Look at the Tcl script again. It already has the lines:

vcom -93 -work work {C:/Users/Alfonso/Desktop/PFC/altera/fixed_float_types_c.vhdl}
vcom -93 -work work {C:/Users/Alfonso/Desktop/PFC/PLL.vhd}
vcom -93 -work work {C:/Users/Alfonso/Desktop/PFC/altera/fixed_pkg_c.vhdl}

Note how the code is being compiled into the library work.

Since it sounds like you are using Quartus to run Modelsim, use Quartus to change the library those two packages are compiled into, eg., right click on the files, and set the library to rtl_work (I think that is how you do it).

Alternatively, just edit the VHDL files and change rtl_work to just plain work, and then it'll work fine.

Cheers,

Dave