I am trying to use Intel Fortran compiler 11.1 for compiling projects of PSCAD. When I installed the compiler, I got an error saying integration in to Microsoft visual studio failed - problem in integrate.bat . This repeats even if I uninstall it, remove all related software and reinstall it again. If I try to run any files in PSCAD with this compiler, I get lot of link errors saying unidentified externals. However, PSCAD recognizes the presence of Intel Fortran compiler. How can I fix this issue? Please help.
You have two very different problems - integration into the Visual Studio IDE has nothing to do with linking issues from a command prompt.
For the Visual Studio issue, see https://software.intel.com/en-us/articles/troubleshooting-fortran-integration-issues-with-visual-studio/ It could be that your Visual Studio version is unsupported by the very old 11.1 compiler.
For linking problems, it would help to see a list of some of the error messages. I recommend that you use the compiler command prompt shortcut installed in the Start menu to create the correct environment and then run your PSCAD builds from there. Since I don't know PSCAD there's a limit to how much help I can provide there.