We investigate the dynamic behavior of vector soliton train propagating in optical media,modeled by the coherently coupled nonlinear Schrodinger(NLS)equation.It is shown that an increase in phase parameters,induces an...We investigate the dynamic behavior of vector soliton train propagating in optical media,modeled by the coherently coupled nonlinear Schrodinger(NLS)equation.It is shown that an increase in phase parameters,induces an increase in intensity of the periodic soliton train,as well as the number of pulses for each transverse electric(TE)and transverse magnetic(TM)mode.From the perturbation approach,when examining the propagation states for the transverse electric and magnetic(TEM)mode,we found a family of three bound-vector soliton states with a different propagation parameter at the first order,representing the three possible distinct vector optical fields reconfiguration of the initial profiles one of which is the‘replication’.At the second order,we obtain an eigenvalue problem with an optical external field,giving rise to five high intensity periodic vector soliton structures described by elliptic functions.Such vector soliton trains are intended to complement single-pulse solitons for multi-channel communication applications.展开更多
The dynamic coupling effect,which is introduced by the dual-sequence phase-locked loops(PLLs)used in doublyfed induction generator(DFIG)based wind energy generation systems(WEGSs)during asymmetric low voltage ride-thr...The dynamic coupling effect,which is introduced by the dual-sequence phase-locked loops(PLLs)used in doublyfed induction generator(DFIG)based wind energy generation systems(WEGSs)during asymmetric low voltage ride-through(LVRT)in weak grid,needs attention.In order to study this new dynamic coupling effect,an equivalent two-degree-of-freedom(2-DOF)spring damper particle model is used in this paper to develop a small-signal model for the dual-sequence PLLs.The dynamic interaction between the positive-sequence(PS)and negative-sequence(NS)PLLs is unveiled.Moreover,the impact of the dynamic coupling between the dual-sequence PLLs on the dynamic stability during the steady-state stage of an asymmetric fault is analyzed.The analysis results show that the dynamic coupling between the dual-sequence PLLs will cause drift in the frequency and damping for the PS and NS PLL modes.This will change the instability modal of the system and introduce the risk of dynamic instability.Hence,the effectiveness of existing control strategies for enhancing the dynamic stability will be decreased.Finally,a novel PLL structure is designed to improve the dynamic stability of the system during the steady-state stage of an asymmetric fault.The effectiveness of the proposed strategy is verified by simulations and experiments.展开更多
文摘We investigate the dynamic behavior of vector soliton train propagating in optical media,modeled by the coherently coupled nonlinear Schrodinger(NLS)equation.It is shown that an increase in phase parameters,induces an increase in intensity of the periodic soliton train,as well as the number of pulses for each transverse electric(TE)and transverse magnetic(TM)mode.From the perturbation approach,when examining the propagation states for the transverse electric and magnetic(TEM)mode,we found a family of three bound-vector soliton states with a different propagation parameter at the first order,representing the three possible distinct vector optical fields reconfiguration of the initial profiles one of which is the‘replication’.At the second order,we obtain an eigenvalue problem with an optical external field,giving rise to five high intensity periodic vector soliton structures described by elliptic functions.Such vector soliton trains are intended to complement single-pulse solitons for multi-channel communication applications.
基金supported in part by the National Natural Science Foundation of China(NSFC)(No.51977019)the Joint Research Fund in Smart Grid(No.U1966208)under a cooperative agreement between the NSFC and State Grid Corporation of China(SGCC)。
文摘The dynamic coupling effect,which is introduced by the dual-sequence phase-locked loops(PLLs)used in doublyfed induction generator(DFIG)based wind energy generation systems(WEGSs)during asymmetric low voltage ride-through(LVRT)in weak grid,needs attention.In order to study this new dynamic coupling effect,an equivalent two-degree-of-freedom(2-DOF)spring damper particle model is used in this paper to develop a small-signal model for the dual-sequence PLLs.The dynamic interaction between the positive-sequence(PS)and negative-sequence(NS)PLLs is unveiled.Moreover,the impact of the dynamic coupling between the dual-sequence PLLs on the dynamic stability during the steady-state stage of an asymmetric fault is analyzed.The analysis results show that the dynamic coupling between the dual-sequence PLLs will cause drift in the frequency and damping for the PS and NS PLL modes.This will change the instability modal of the system and introduce the risk of dynamic instability.Hence,the effectiveness of existing control strategies for enhancing the dynamic stability will be decreased.Finally,a novel PLL structure is designed to improve the dynamic stability of the system during the steady-state stage of an asymmetric fault.The effectiveness of the proposed strategy is verified by simulations and experiments.
