Wuhan Ligong Daxue Xuebao (Jiaotong Kexue Yu Gongcheng Ban)/Journal of Wuhan University of Technology (Transportation Science and Engineering)

Abstract : Power electronics circuits are characterized by nonlinear dynamics, originating in cyclic topological transitions in circuits. The power converters, which are an integral component of power electronics circuits, ensure power conversion between power source and load. The nonlinear dynamics in DC-DC converters result under variations in converter parameters, load, reference voltage and current. In nominal operating conditions, such converters exhibit a stable period-1 switching cycle. In nonlinear operation, bifurcation, chaotic behavior, quasi-periodicity, and period doubling may result, yielding insights on system malfunctions. This work is aimed towards analyzing and modulating the nonlinear behavior exhibited by the Buck converter. The converter is in voltage mode control (VMC) and in continuous conduction mode (CCM) and is described by a mathematical formulation and simulated in MATLAB. Systematic variations in parameters of the converter recognize that the switching converter is able to exhibit aberrant behaviors including bifurcation, quasi-periodic, and chaotic behavior, and thus may produce instable system behavior. Our contributions include applying Spotted Hyena Optimizer (SHO) technique in simulation and experimental implementation to optimize the operation of the Buck converter and to eliminate nonlinear effects including bifurcation, double periodicity, and chaos. The technique is directed towards optimizing PID controller parameters by minimizing variation between reference voltage and observed values to ensure greater stability and efficiency. A Buck converter prototype is developed and regulated in real time using a dSPACE 1104 card. The proposed technique is validated through computational and experimental data, indicating its ability to minimize nonlinear effects in the Buck converter. The obtained results improve the important of this approach to ameliorate the performance of the Buck converter and eliminate the undesirable phenomenon.