Switching synchronization states of a ring of coupled chaotic circuits with one-direction delay effects
Synchronization states can be observed in coupled circuits. Further, interesting synchronization states were confirmed in coupled chaotic circuits containing time delay. In this study, we investigate the novel coupling methods and synchronization states observed in coupled chaotic circuits containing time delay. The novel coupling methods is a ring of coupled chaotic circuits with one-direction delay effects. Synchronization state observed the novel coupling methods is switching synchronization state. The switching synchronization state is changed by time delay of each subcircuit. We focus on relationships between switching synchronization state and the pattern of time delay. Moreover, we investigate the cycle of switching synchronization state.
This paper analyzes the behavior of DFIG and converter in the case of grid fault including symmetrical and unsymmetrical fault. First, the simple space vector models are presented to estimate the moduli of DFIG stator voltage in different grid fault. Then with the symmetrical components method, the dynamic response of DFIG and converter in grid fault is analyzed in details, and the equations of grid fault are derived. According to the equation, the maximum value and it's occurred moment of the short-current of DFIG is determined, which can be used to design crowbar precisely. At last, based on the above analysis, the design guidelines for grid fault ride-through are proposed.