Power electronics is a discipline spawned by real-life applications in industrial, commercial, residential, and aerospace environments. Much of its development revolves around some immediate need for solving specific power conversion problems. This comprehensive book focuses on the typical bifurcation scenarios and nonlinear behavior observed in switching power converters, expounding on their most relevant aspects from a practical viewpoint. A balanced emphasis on theory, computer methods, and laboratory experiments bridges the gap between the theoretical research and practical engineering applications.

Complex Behavior of Switching Power Converters

Power electronics circuits are rich in nonlinear dynamics. Their operation is characterized by cyclic switching of circuit topologies, which gives rise to a variety of nonlinear behavior. This paper provides an overview of the chaotic dynamics and bifurcation scenarios observed in power converter circuits, emphasizing the salient features of the circuit operation and the modeling strategies. In particular this paper surveys the key publications in this field, reviews the main modeling approaches, and discusses the salient bifurcation behaviors of power converters with particular emphasis on the disruption of standard bifurcation patterns by border collisions.

/pdf/complex-behavior-in-switching-power-converters-1stelymp8h.pdf

Complex behavior in switching power converters

Permanent magnet synchronous motor (PMSM) will demonstrate chaotic phenomena when its parameters fall into a certain area. The performance of PMSM will degrade because of chaos. Therefore, chaos should be suppressed or eliminated. According to the features of this practical plant, the drawbacks of existing control methods are analyzed, and the nonlinear feedback control method is suggested to control the chaos in PMSM. The nonlinear feedback principle is developed using the direct axis and the quadrature axis stator voltage as manipulated variables. The control target will become a unique asymptotically stable equilibrium under the nonlinear feedback principle, by this way, the controlled states can reach the target and the control objective can be implemented. This method can be physically realized using nonlinear state feedback. The control forces can be put into effect at any time. The target of the method may be any point in the strange attractor. The influence of the model error and the measurement noise upon the control performance is studied via simulations. Simulation results show the effectiveness of this method under the presence of the model error and the measurement noise

Nonlinear feedback control of chaos in permanent magnet synchronous motor

An adaptive fuzzy control method is developed to suppress chaos in the permanent magnet synchronous motor drive system via backstepping technology. Fuzzy logic systems are used to approximate unknown nonlinearities and an adaptive backstepping technique is employed to construct controllers. Compared with the conventional backstepping, the designed fuzzy controllers’ structure is very simple. The simulation results indicate that the proposed control scheme can suppress the chaos of PMSM drive systems and track the reference signal successfully even under the parameter uncertainties.

Adaptive fuzzy tracking control for the chaotic permanent magnet synchronous motor drive system via backstepping

In this paper, chaotic behavior in current-mode-controlled dc drive systems has been analyzed. The key is to derive an iterative map that describes the nonlinear system dynamics. Analytical modeling of fundamental and subharmonic oscillations as well as their stability analysis are presented. The results show that current-mode-controlled DC motor drive systems generally exhibit chaotic behavior. To avoid the occurrence of chaos, the stable ranges of various system parameters are determined. Both computer simulation and experimental measurement are given to verify the theoretical analysis.

/pdf/analysis-of-chaos-in-current-mode-controlled-dc-drive-4hxdnt1vxz.pdf

Analysis of chaos in current-mode-controlled DC drive systems

Instability phenomena in power electronic induction motor drive systems are investigated from the point of view of bifurcation theory. A method to determine bifurcation values of system parameters is discussed. It is shown that some kinds of bifurcations are observed in power electronic induction motor drive systems. The proposed method makes it possible not only to determine instability regions of system parameters, but also to investigate qualitative properties of the instability phenomena. >

S. Hayashi

Papers

Analysis of bifurcation in power electronic induction motor drive systems