<?php
use PhpOffice\PhpWord\SimpleType\DocProtect;

include_once 'Sample_Header.php';

// New Word Document
echo date('H:i:s') , ' Create new PhpWord object' , EOL;
$phpWord = new \PhpOffice\PhpWord\PhpWord();

$documentProtection = $phpWord->getSettings()->getDocumentProtection();
$documentProtection->setEditing(DocProtect::READ_ONLY);
$documentProtection->setPassword('myPassword');

$section = $phpWord->addSection();
$section->addText('this document is password protected');

// Save file
echo write($phpWord, basename(__FILE__, '.php'), $writers);
if (!CLI) {
    include_once 'Sample_Footer.php';
}