Global Frequency Synchronization of Complex Power Networks Via Coordinating Switching Control

It is well known that the frequency synchronization of complex power networks is a prerequisite for stable operation. This paper investigates the global frequency synchronization in power networks via coordinating novel controllers on both the generator-side and the load-side. The designed controllers compute the monitored information from the generator-side and load-side simultaneously, and transmit the processed signals to steer the generators and load buses for maintaining frequency stability. In particular, the generator (load)-side buses can communicate with the load (generator)-side buses, not limited to the same side. Furthermore, nonlinear switching control protocols are proposed to analyze the frequency stability for overcoming the deficiency that the conventional linearized methods can only guarantee the local stability in or near an equilibrium state. The global stability region is rigorously proven, in which the sufficient conditions are derived for achieving global frequency synchronization of power systems. Finally, a prevailing modified Western System Coordinating Council (WSCC) 9-bus system and the widely-used IEEE 39-bus system are selected to validate the effectiveness and feasibility of the theoretical results.