CRMBoostPFC变换器的传导EMI研究

摘要：Boost电路是功率因数校正变换器中常用的拓扑结构之一，具有结构简单、功率因数高、输入电流脉动小等优点。Boost PFC变换器既可以工作在电感电流连续模式下，也可以工作在电感电流临界连续模式和电感电流断续模式下。本文主要研究了单路CRM Boost PFC变换器。本文首先分析了在不同的工作状态下，在一个开关周期中，电感电流的峰值、有效值和开关频率的数学表达式，并根据表达式画出变化曲线。然后采用峰值电流控制方法来控制PWM波，并且控制了MOSFET管的通断。同时，分析升压电感，以及输出电容的参数并给出设计。最后，设计出一个输入为220V，输出为385V的仿真电路，电路的仿真结果与预想结果基本吻合，设计成功。

本文还研究了CRM Boost PFC变换器的传导电磁干扰的频谱特性。为了分析变换器开关管漏源极电压谐波的谐波频和共模、差模干扰频谱，本文采用了短时傅里叶变换的分析方法。根据EMI接收机的实际工作原理，计算研究了变换器地传导EMI的峰值、准峰值和平均值。分析了共模和差模干扰谐波频谱与EMI的峰值和平均值之间存在的关系。然后，根据以上的关系推导了当输入电压为工频电压时，CRM Boost PFC变换器的传导EMI频谱特性，最后根据频谱特性，设计出了PFC变换器的EMI滤波器。

关键词：功率因素校正 Boost变换器传导电磁干扰 EMI滤波器

毕业设计说明书外文摘要

Title Electromagnetic interference study of CRM Boost PFC converter

Abstract：The Boost circuit has simple structure, high Power Factor, and the advantages of small input current ripple, is the Power Factor Correction (Power Factor Correction, PFC) converter is commonly used in one of the topology. Boost PFC converter works in the inductor current critical continuous mode (CRM), the converter can not only realize the opening of the switch tube zero current and diode zero current turn off, and high power factor, has been widely used in low and middle power transformation. This topic mainly aimed at small power Boost PFC converter design study, master the Boost PFC converter of common mode and differential mode interference characteristics, and the frequency spectrum characteristics; Fully understand the characteristics of the power factor correction technology and CRM control, the detailed design scheme of the converter and filter is given and the simulation research and experimental verification. This design mainly for CRM Boost PFC converter design of study and research, through the theoretical analysis of working principle of the control circuit, through the simulation analysis and actual circuit test, the converter conduction EMI design work for validation.

Keywords：PPC；boost converter；conducted electromagnetic interference； filter

1 绪论 1

1.1 电磁兼容背景 1

1.2 Boost功率因数校正变换器 2

1.3 CRM Boost PFC变换器的传导电磁干扰 4

1.4 研究意义巧研究内容 4

2 CRM Boost PFC变换器设计 5

2.1 引言 5

2.2 CRM Boost PFC变换器 5

2.3 参数设计 10

2.4 电路仿真分析 10

3 CRM Boost PFC变换器的传导电磁干扰分析 CRMBoostPFC变换器的传导EMI研究:http://www.chuibin.com/zidonghua/lunwen_205614.html