【作者】 袁臣虎；

【导师】 万健如；

【作者基本信息】 天津大学 ， 电力电子与电力传动， 2012， 博士

【摘要】 DC/DC变换器作为开关电源(Switch Mode Power Supply,SMPS)系统重要组成部分,当其电路参数和拓扑结构改变时,系统呈现出丰富的非线性特性,影响SMPS系统稳定性和工作特性。本文研究DC/DC变换器电路参数对SMPS系统稳定性影响,为DC/DC变换器应用于SMPS系统时的电路参数设计提供依据。并且针对DC-DC电路拓扑不具有普适性问题,研究一种新型的DC-DC变换器电路拓扑,研究该变换器工作原理、参数特性和参数设计方法,并进行实验验证。本文主要研究内容和创新性成果如下:1.在建立BUCK变换器精确状态方程基础上,搭建电压反馈型BUCK变换器无差仿真模型,研究不同电路参数对VCBUCK变换器稳定性影响。研究结果表明,输入电压、储能电感、输出滤波电容、误差比例系数是影响VCBUCK变换器稳定性的关键电路参数,积分系数和负载对VCBUCK稳定性影响较小。2.在研究电压反馈型双端DC/DC变换器各开关模态的基础上,指出可将其等效为开关频率加倍的VCBUCK变换器,利用等效VCBUCK变换器仿真模型研究不同电路参数对双端DC/DC变换器稳定性的影响。研究结果表明,电路参数对其稳定性影响与VCBUCK变换器类似。3.在构建电流反馈型BUCK变换器双闭环仿真模型基础上,研究不同电路参数对其稳定性影响。研究结果表明,输入电压、输出滤波电容、误差比例系数是影响PCCBUCK变换器稳定性的关键参数,而储能电感、积分系数和负载在一定范围内变化时对PCCBUCK变换器的稳定性影响较小;VCCBUCK变换器稳定性对输入电压、储能电感、输出滤波电容、误差比例系数敏感,而当积分系数和负载在一定范围内改变时不影响VCCBUCK变换器稳定性,且输入电压对二者稳定性影响过程相反。4.在建立BOOST变换器精确状态方程基础上,搭建电流反馈型BOOST变换器双闭环仿真模型,研究不同电路参数对其稳定性影响。研究结果表明,输入电压是影响其稳定性的关键参数,输入电压的变化会使系统由周期1态经倍周期分岔最后激变至混沌态,且输入电压对PCCBOOST变换器与VCCBOOST变换器稳定性影响过程相反,其它电路参数对电流反馈型BOOST变换器稳定性影响较小。5.提出一种新型变换器拓扑—并联谐振倍压变换器(PRDVC),在分析该变换器电路拓扑和建立其状态方程基础上,研究该变换器的工作模式、参数特性和参数优化设计方法。研究结果表明,PRDVC有如下优点:①利用谐振技术实现了软开关,提高了开关频率和变换效率;②PRDVC拓扑吸收利用了高频变压器分布电容和漏感,减少了分布参数对系统稳定性影响,有效改善电源系统的EMC,使其稳定可靠工作;③利用倍压整流电路和变压器来共同完成升压任务,使得变压器制作难度和体积减小,满足了高压电源小型化要求。文中对以上研究内容均进行了相应的实验验证,给出了必要的实验波形,并对实验结果进行了分析和解释。实验结果与理论分析和仿真结果吻合,本文的研究成果和研究方法具有实用价值。更多还原

【Abstract】 DC/DC converter is an important part of SMPS system and it has rich nonlinear dynamical characteristic when circuit parameters and circuit topology changed, which could affect the stability and performance characterists of system. The influence of circuit parameters of DC/DC converter on stability of SMPS system were researched in the thesis. The research results could provide the basis for the design of parameters when DC/DC converter applied to SMPS system. As DC/DC converter could not be applied to all occasions, a novel circuit topology for DC/DC converter was developed. The circuit principle, parameters characteristic and parameter design method were studied in detail and verified in experiments.The main contents and innovative research in the dissertation were summarized as follows:1. Zero error simulation model of voltage control BUCK converter was constructed based on the exact state equations of BUCK converter. The influence of different parameters on the stability of VCBUCK converter was researched. The results proved that stability of VCBUCK converter was senstive to input voltage, storage inductor, output filter capacitor, scale factor but not to integration factor and load.2. Voltage control double-ended DC/DC converter was equivalent to doubled-switch frequency VCBUCK converter based on its switch modes. According to the equvialent simulation model of VCBUCK converter the influence of different parameters on the stability of voltage control double-ended DC/DC converter were researched. The results verified that the influence characteristic of parameters on it was similar to VCBUCK converter.3. Double loop simulation model of current control BUCK converter was constructed, based on which the stability of CCBUCK was studied in different parameters. The experiments verified that stability of PCCBUCK converter was senstive to input voltage, output filter capacitor, and scale factor but not to integration factor, storage inductor and load. And the stability of VCCBUCK converter was senstive to input voltage, storage inductor, output filter capacitor, scale factor but not to integration factor and load. The influence characteristic of input voltage on PCCBUCK converter and VCCBUCK converter were contrary.4. Double loop simulation model of current control BOOST converter was constructed based on the exact state equations of BOOST converter. The influences of different parameters on the stability of CCBOOST converter were researched. The results proved that input voltage was the vital parameter to stability of CCBOOST converter. With variation of input voltage the system operation state transferred from 1-period to chaos through double period bifurcation. And the influence characteristic of input voltage on PCCBOOST converter and VCCBOOST converter were contrary. Other parameters had no impact on stability of CCBOOST converter.5. A novel converter topology, namely parallel resonant dual voltage converter was developed. The operation modes, parameter characteristic and parameter optimization design method of PRDVC were researched in detail based on its circuit topoloty and state equations. Results showed that PRDVC had many merits compared to other converters, which were listed below.①The switch frequency and efficiency were improved by using soft switch which was accquired by resonant technology.②Distributed capacitor and leakage indcutor in high frequency transformer were absorbed by PRDVC topolgy. The influence of distributed parameters was reduced in order to improve EMC and reliability of system.③Dual voltage rectifying circuit and transformer were both used to boost voltage. Therefore, the problems of bigger volume and heavy degree of difficuity in making were solved, which was suitable for miniaturization high-voltage power supply.The experiments were performed to verify the research contents and the corresponding waveforms had been presented. The experiment results showed that the theory analysis and simulations were consistent with the experiments. The methods and achievements in the dissertation have the practical value.更多还原