I want to understand the decentralized control for large scale systems. I study from book entitled "Large Scale Systems-jamshidi" but this book does not explain everything.
A very good book to start with is Leon Lasdon's book "Optimization Theory for Large Systems". It was originally published in 1970, but recently was re-published by Dover Publications. It explains how you may "decompose" a large-scale problem into subproblems that are easier to solve, and then through coordinating problems you can "assemble" the optimal solution. It's a very nice book to read. While it is not up-to-date on efficient methods, it gives you very good insights into how decentralisation (or, decomposition) and coordination works.
Let me know if you cannot find it, and I'll give you links.
At Google books you can browse several pages, but downloading the whole book is not possible. On the other hand, at Dover's home page you can buy it for $30.