不连续导电模式Boost PFC变换器中快尺度不稳定性研究

导出了不连续导电模式Boost PFC变换器的异步切换映射数值模型。数值模拟发现,系统在输入电压周期里会出现快尺度边界碰撞分岔现象。通过研究电路系统模式的切换临界角的变化对快尺度不稳定性现象进行了详细的描述,同时分析了快尺度不稳定性对器件应力及系统功率因数的影响,给出了系统稳定性随一些参数变化的稳定性区域图。最后,实验验证了这种快尺度不稳定性现象的存在。这些结果对于实际电路的设计具有重要的参考价值。

Fast-scale instabilities in Boost PFC converters operating in discontinuous conduction mode

Asynchronous switching maps are derived to describe entirely the dynamics of Boost PFC converters operating in discontinuous current mode.Numerical simulations reveal that the fast-scale border collisions may occur within a line cycle and describe these nonlinear phenomena in detail in terms of the investigation of the critical phase angles of the circuit system operation mode switch.Furthermore,the influences of the fast-scale instabilities on switches and performance of the system are analyzed,and the stability region diagrams in parameter space are provided with the change of some important circuit parameters.Finally,experimental results verify that the system can exhibit fast-scale instable phenomena,and agree with the simulation results.All these results are very useful to the design of practical circuits.