Initial part of the book focuses on synchronization phenomenon commonly observed in complex networks.. Considering transient stability in power system as a special type of synchronization problem, issues regarding modelling of multi-machine power system especially when TCSC is used as a controller are discussed. With the example of disturbance in the NEW grid, in July 2012 an emphasis is given on the need to control line loadability along with rotor angle stability to maintain grid integrity which resulted in necessity of Kuramoto Mean Field Model. Solution of this multi-dimensional problem felt the need of an efficient optimization tool. A convex optimization problem is formulated providing an edge-weight control to match the post-fault conditions of the power system to its pre-fault healthy conditions, maintaining the demand-supply balance, rather than an obvious solution of load shedding in case of critical line contingency. Last part describes a drift vector decomposition method to generate a potential function to derive suitable control law without solving PDEs. The method has effectively addressed the long-lasting problem of finding a control law for lossy n-machine systems