Does writing a book improve your chance for getting scholarship for applying PhD abroad?

As you know there are many candidates competing for winning the scholarship for their PhD program, specially the ones who are applying abroad. So having better skills likely spell to overcome the other candidates.

I have two SCI papers in my field. So I don't have a very bad research background as a graduated student of electrical Engineering for M.SC. degree. But, recently, I've started to write a book in English. The content of book is very general and simple but still can be fitted in my field. The book title is going to be 'Technical language in electrical engineering'. This book is one of the courses of Electrical Engineering for B.Sc degree in some countries.

So, since the books are not usually peer-reviewed, I was wonder to ask:

1. How much does writing a general and simple book in your field help you to get a good scholarship for PhD program?


2. Is the effect of writing a book more than a namely research paper?


3. Is the affects of having a book different in different countries? If yes, please tell me about Australia, US and Canada for precise.


4. Is it okay if I self-publish the book or I need a good publisher?