单开关高增益升压变换器的仿真研究设计论文.doc

(此文档为word格式，下载后您可任意编辑修改！) 摘要 小功率光伏或燃料电池发电系统，因为电池电压很低，通常需要电压增益高达 10 倍以上的直流变换器将其升压后经逆变器输出。经典 Boost 变换器要实现高电压增益需宽占空比导通，然而宽占空比导通、高压输出下二极管反向恢复会造成严重的开关损耗及电磁干扰等问题；高匝比的反激变换器可以实现高电压增益，但在低压输入高压输出的场合原边匝数少，漏感大，需箝位电路限制开关器件电压应力， 能量不能高效地传输。 主要研究内容如下：阐述了Flyback-Boost非隔离型高增益直流变换器工作原理，并在此基础上给出了各个元器件的参数设计，对比传统Boost直流变换器的优缺点，保留了传统 Flyback 变换器器件数目少、电路结构简单的优点，同时又具有电压增益和效率高的特点，确定了基于串联技术直流变换器总体设计方案。 分析了直流-直流变换器的动态特性，并对直流变换器进行了建模，然后根据得到的模型设计了合适的PI控制器，减少了动态响应时间，提高了噪声抑制性能，增强了系统的稳态特性。采用边界整定法试凑出满足要求的PID参数，给出了合理合乎指标要求的PID参数。 对基于串联技术的直流变换器不同的工作模式进行了仿真调试，测试了在不同条件下的输出电压、电流波形。通过分析仿真结果，验证了该变换器的可行性，实现了高升压比和低纹波输出。 关键词：高增益；反激升压；单开关管；低纹波 Abstract Low power photovoltaic or fuel cell power generation system, because the battery voltage is low, usually need to dc converter voltage gain as much as more than 10 times of its booster after the inverter output.Classic Boost converter to achieve high voltage gain compared to wide conduction, however wide under the duty ratio conduction, high voltage output diode reverse recovery willcause serious switching loss and emi problem;High turn ratio of the flyback converter can achieve high voltage gain, but in place of low voltage input highvoltage output less the original edge number of turns, the leakage inductance of the big, need to clamp circuit limit switch voltage stress, energy of effective transmission. The main contents are as follows: elaborated Flyback-Boost non-isolated DC-DC converter works in high gain.On this basis, the design parameters of various components is calculated.Compared to advantages and disadvantages of the traditional Boost DC-DC converter, this device preserves the advantagesthe oftraditional Flyback converter device which are less number components ,small and simple circuit structure , but also has a high voltage gain and efficiency.So it determines this DC converter based on the cascade technology. Analysis of DC converter dynamic characteristic, and DC converter is modeled.It get design PI from controllerthe right model ,which c