恒流源负载V2控制Buck变换器的稳定性分析.pdf

第38卷第4期
自め化耒
Vo】.38No.4
2017年4月
PROCESS AUTOMATION INSTRUMENTATION
Apr.2017
恒流源负载控制Buk变换器的稳定性分析
吴志敏,杨艳,史国栋,包伯成,姚凯文
(常州大学信息科学与工程学院,江苏常州213164)
摘要;恒流源负载开关变换器在发光二极管照明领域具有广阔的应用前景,其研究具有理论意义和应用价值。为了研究电路参数
对恒流源负载控制Buck变换器稳定性的影响,建立了该变换器的二阶离散迭代映射模型,得到了输出电容等效串联电阻、恒流源
负载变化时的分岔图。分析结果表明,当输出电容等效串联电阻恒流源负载变化时,恒流源负载控制Buck变换器具有复杂的动
力学行为。利用特征值和最大李雅普诺夫指数对系统进行稳定性分析,验证了分岔分析的正确性。通过数值仿真得到了输出电容及
其等效串联电阻之间的工作状态边界,揭示了输出电容时间常数稳定临界值与开关周期间的非线性关系。最后,基于PSIM电路仿真
和电路试验,得到了输出电容等效串联电阻时的时域波形,验证了二阶离散迭代映射模型的有效性和理论分析的正确性。
关键词:电力电子;二极管;恒流源负载;Buck变换器;输出电容;稳定性分析
中图分类号:TH82;TP391
文献标志码:A
DOI:10.16086/j.cnki.issn100-0380.201704017
Stability Analysis of V"Controlled Buck Converter
with Constant Current Source Load
WU Zhimin, YANG Yan, SH Guodong, BAO Bocheng, YAO Kaiwen
(School of Information Science and Engineering, Changzhou University, Changzhou 213164, China)
Abstract: Switching converter with constant current source load has a wide application prospect in the lighting field of emitt
diode, and therefore he study of V controlled buck converter with constant curent source load has theoretical significance and
application value. In order to investigate the influence of circuit parameters on stability of V2 controlled buck converter with
constant current source load, a second order discrete iterative mapping model is established, based on which the bifurcation
diagrams with the variations of the equivalent series resistance of output capacitor and constant current source load are obtained
The results show thal the converter has complex dynamic behavior when the equivalent series resistance of output capacitor
and constant current source load change. Stability of the system is analyzed by using the eigenvalues and maximum Lyapunov
exponent, which validates the correctness of bifurcation analysis. The operation state boundaries between the output capacitor
and its equivalent series resistance are obtained by numerical simulations, and the nonlinear relationship between the stable
critical value of output capacitor time constant and the switching cycle is revealed. Based on PSM circuit simulations and circuit
experiments, the time domain waveforms under different equivalent series resistance of output capacitor are received. Thus, the
effectiveness of the second order discrete iterative mapping model and the correctness of theoretical analysis are verified
Keywords: Power electronics; Diode; Constant current souree load; Buck converter; Output capacitor; Stability analysis
具有重大的理论意义和应用价值。
0引言
开关变换器存在低频波动、次谐波振荡、倍周期分
发光二极管( light emitting diode,LED)照明是通岔、边界碰撞分岔和不稳定混沌振荡等非线性动力学
过控制IED负载实现恒流照明,在实际开关变换器现象3-?。不稳定混沌振荡的出现会极大地影响开关
中,LED负载可等效为恒流源负载,故恒流源负载开变换器的控制性能,甚至导致开关变换器无法正常工
关变换器是今后电力电子的重要研究和应用方向。作。因此,有必要运用动力学方法对开关变换器中存
v2控制因其快速的动态响应而得到广泛关注2,因在的一系列非线性动力学现象进行研究,同时深入分
此,对恒流源负载P控制Buek变换器进行深人研究析电路参数的变化对变换器稳定性的影响,以指导开
修改稿收劉日期:2017-01-16
基金项目:常州市自然科学基金资助项目(CJ20159026)
作者简介:吴志敏(1977ー),女,硕士,讲师,主要从事电能变换与控制技术的研究。E-mail:zhimin@ccu.edu.cn。
杨艳(通信作者),女,在读硕士研究生,主要从事电能变换与控制技术的研究。E-mail:yangyan_Tiffany@163.com
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