Hidden dynamics of an optically injected laser diode subject to threshold electromagnetic induction: coexistence of multiple stable states

In this contribution, we perform a detailed study of the effect of electromagnetic induction on the dynamical behavior of laser diode modeled by novel single-mode four-dimensional rate equations. Memristor is used to describe electromagnetic induction effect. As result, the obtained model is equilibrium free thus displays hidden dynamics. Consequently, Shilnikov method is not suitable to explain the chaos mechanism in the introduced laser model. Furthermore, there is no heteroclinic nor homoclinic orbit. Based on numerical simulations, we found that the laser model displays hidden dynamics including period doubling bifurcation, multistability (with three different stable states) and crisis phenomena when the electromagnetic strength is varied. The circuit emulator of laser model investigated in this paper has been designed in the Pspice environment to further support numerical results

A simplified nonlinear controller for transient stability enhancement of multimachine power systems using SSSC device

International audienceIn this paper, a simplified nonlinear method is proposed to enhance the transient stability of multimachine power system by using a Static Synchronous Series Compensator (SSSC). The rate of dissipation of transient energy is used to determine the additional damping provided by a SSSC. The proposed algorithm is based on the direct Lyapunov method. The simplicity of the proposed scheme and its robustness with respect to large disturbances constitute the main positive features. Simulation results in the case of 3-machines power system show the effectiveness of the proposed method under large disturbances (3-phase and single phase short-circuits)