This simple PowerShell script will read through a directory and convert all Microsoft Word files (.doc, .docm and .docx) into PDF files. Simply change the code to reflect the target directory.

$path = "c:\path\to\files" #Target directory for converting Word files
$word_app = New-Object -ComObject Word.Application

#Convert .doc and .docx to .pdf
Get-ChildItem -Path $path -Filter *.doc? | ForEach-Object {
    $document = $word_app.Documents.Open($_.FullName)
    $pdf_filename = "$($_.DirectoryName)\$($_.BaseName).pdf"
    $document.SaveAs([ref] $pdf_filename, [ref] 17)
    $document.Close()
}
$word_app.Quit()

A -Recurse function can be added if required.

PDF files will be output to the same directory as their progenitor .doc/.docx files and will share the same file name.