Buck变换器DCM模式下的动态建模分析  

Dynamic modeling analysis on Buck DC-DC converter working in DCM

作　　者：沈建冬[1] 张莉[2] 赵勇[1] 

机构地区：[1]西安邮电大学自动化学院,陕西西安710121 [2]西安工程大学电子信息学院,陕西西安710049

出　　处：《西安邮电大学学报》2013年第4期41-45,共5页Journal of Xi’an University of Posts and Telecommunications

基　　金：国家青年自然科学基金资助项目(51205309);西安邮电学院青年教师科研基金资助项目(ZL2011-10)

摘　　要：为了解决断续电流模式下的Buck直流变换器建模困难的问题,针对这个离散的、时变的、非线性系统,提出引入虚拟开关数将一个开关周期中的三种电路拓扑统一到一组状态空间方程中。在应用动态相量法时,为保证模型的合理性,动态相量模型中保留傅里叶级数中的直流量、基频分量和二次分量,讨论虚拟开关占空比的取值,建立其非线性、大信号、时不变模型。仿真结果表明,动态相量模型接近于时域模型,验证了动态相量模型的合理性。In order to solve the problem of modeling on the Buck DC-DC converter working in discontinuous conduction mode（DCM）,which is a discrete,time-varying,nonlinear system,three circuit topologies in a switching cycle are unified to a set of state space equations by a virtual function.When using the dynamic phasor,the DC component,fundament frequency component and second harmonic components of Fourier series are retained in order to ensure the rationality of the model.The value of the virtual switch duty cycle is discussed and a non-linear,large signal,time-invariant model is built.Simulation results show that the dynamic phasor model is similar to the time-domain model.Its validation is also proved.

关 键 词：Buck直流变换器 断续电流模式 动态相量法 虚拟开关 

分 类 号：TP273[自动化与计算机技术—检测技术与自动化装置]