恒功率负载下DC-DC双向变换器分岔现象研究

Research of bifurcation phenomenon of DC-DC bidirectional power converter with constant power loads

研究了基于多级功率变换器下的直流微网结构,提出恒功率负载研究方法,建立了直流微网简化模型;根据简化模型,建立了DC-DC双向变换器在不连续运行模式下的离散映射,给出了系统稳定运行状态下迭代方程和反馈系数的计算公式;根据迭代方程得出电压与反馈系数的分岔波形图。电路仿真和实验结果表明,随着反馈系数的增大,系统将从稳定状态到分岔状态并逐渐过渡到混沌状态。

The DC micro-grids architecture based on multistage power converter was studied,the research method of constant power load was proposed and the simplified model of DC micro-grids was built.According to the simplified model,the discrete mapping with DC-DC bidirectional converter operating in intermittent mode was built,and the iterative equation and computational formula of feedback factor in stable condition were given.The bifurcation waveform between output voltage and feedback factor was obtained according to iterative equation.Simulation and experiment results show that by increasing the feedback factor,the circuit will work from stable condition to bidirectional point and run into chaos eventually.