【作者】 司冬子；

【导师】 杨荫福；

【作者基本信息】 华中科技大学 ， 电力电子与电力传动， 2005， 硕士

【摘要】 高功率密度、高效率和高性能是现代电力电子功率变换器不断追求的目标,功率因数校正和软开关技术为此提供了有效的方法。因此本文介绍了一种前端带功率因数校正的串并联负载谐振式DC/AC 变换器。文章首先介绍了功率因数校正电路的工作原理,并以均值电流控制的BOOST 电路为例,分析了输入电流中三次谐波的产生与抑制以及控制系统的设计方法和设计过程。接着对负载谐振式逆变器进行了分类并比较了他们的特点,最终采用了串联谐振、电容分压输出的拓扑结构。该电路结构集成了串联谐振逆变器和并联谐振逆变器的优点,在开关频率略小于谐振频率时可以实现开关管的软开关; 如果选择合适的参数,可以做到对无功负载的近似无差调节。文中还介绍了该电路的工作原理以及简化的等效电路; 详细地分析了逆变器的负载特性以及负载变化对逆变器工作特性的影响; 并总结出了谐振电感和电容的选取原则。两级电路各自构成独立闭环回路,前级采用PWM,后级采用移相控制调压,工作简单、可靠。最后对电路进行了仿真和实验,实验结果表明,该方案是可行的,该方案对高频逆变领域具有一定的参考价值。更多还原

【Abstract】 High power density as well as high efficiency has always been the goal to pursue in the field of moden electric power converters, Power Factor Correction(PFC) and soft switch provide an effective way. So, this paper presents a series-parallel resonant inverter with PFC ahead. the paper introduces the principle of PFC rectifier with the average current mode controlled circuit as an example, analysing the producing of third harmonic of input current and restraining it ,at last giving a methord of designing control system. By classifying load resonant inverters and comparing their characteristic ,a topology of series resonant inverter with output from resonant capacity is proposed. The topology integrats the advantage of series resonant inverter and parallel resonant inverter. As it works below the resonant frequency, soft switching will be achieved, and the circuit could reach indiscrimination to reactive load approximately. The paper describes the principle of this circuit , analysising the identity of load and the change of load working on the inverter in detail, summarizing the principle of selecting resonant induction and capacity. The control of the two circuits is unattached, the former adopts PWM and the latter introduces phase-shifted control to adjust output,working simply and safely. Finally, simulation and experiment are carried out, the experimental result indicates that the project is feasible, this scheme could be used in the fields of high frequency inverter.更多还原