AOT控制的降压型转换器的稳定性分析  

Analysis on Stability of AOT Controlled Buck Converter

作　　者：徐婷婷 柴常春[1] 王艳秀 刘彧千 XU Tingting;CHAI Changchun;WANG Yanxiu;LIU Yuqian(School of Microelec.,Xidian Univ.,Xi’an 710071,P.R.China;Shanghai Will Semicond.Ltd.,Shanghai 201203,P.R.China)

机构地区：[1]西安电子科技大学微电子学院,西安710071 [2]上海韦尔半导体股份有限公司,上海201203

出　　处：《微电子学》2019年第6期829-833,共5页Microelectronics

基　　金：国家自然科学基金资助项目(61634004)

摘　　要：为了保证自适应导通时间控制的降压型转换器能在输入电压全范围内正常工作,通过理论分析和时域推导,研究了输出电容的ESR对系统稳定性的影响。结果表明,只有ESR足够大,才能保证其电压变化率大于输出电容电压变化率,从而保证系统的稳定。此外,建立了ESR的最小临界值与输入电压之间的数学模型,并揭示了二者存在反比例关系。不同ESR条件下的输入电压扰动时域仿真结果说明了ESR对系统稳定的重要性。通过比较理论数学模型的拟合曲线与实际仿真结果,验证了理论分析和数学模型的正确性。In order to guarantee that the system could work in the whole range of input voltage,the effect of equivalent series resistance(ESR)of the output capacitor on the stability of adaptive on-time(AOT)controlled buck converter was studied.Theoretical analysis and time-domain derivation were provided to understand the impact of ESR on system stability.It was indicated that only if the value of ESR was large enough,the rate of change in voltage across ESR would be higher than that across the output capacitor,thus ensuring system stability.In addition,the mathematical model between critical lower-bound ESR value and the input voltage was established,and the results indicated that the critical ESR and input voltage had a relationship of inverse proportion.The input voltage disturbance domain was simulated at different ESRs,and the results showed that the ESR had an important role on the system stability.By comparing the fitting curves of theoretical analysis model and the simulated actual values,the correction of theoretical analysis and mathematical model was verified.

关 键 词：降压型转换器 自适应导通时间 等效串联寄生电阻 稳定性 

分 类 号：TM46[电气工程—电器] TN86[电子电信—信息与通信工程]