摘要:开关电源等电力电子装置在电力系统、工业、家庭等方面得到广泛使用,在造福人类的同时也产生了不可忽视的谐波问题。为了对电流脉冲的幅度进行抑制,让开关电源输入电流谐波达到要求,由此引进了功率因数校正技术。本文首先介绍了几种一般的应用于有源功率因数校正的主电路拓扑,并详细阐述了相关的控制策略,分析了基本无桥PFC功率因数校正电路的原理,进而提出了一种基于平均电流控制芯片UC3854的改进型无桥功率因数校正变换器。最后通过对参数的选取实现对BOOST电感的计算、输出滤波电容的计算、最大输入功率和输入电流的计算以及输入电容及开关器件的选型设计了主电路,并采用UC3854芯片设计了控制电路,采用TLP250芯片设计了驱动电路,采用一个采样电阻设计了采样电路,保护电路采用常见的限压限流方式,实现了电路的设计。55185
毕业论文关键词:无桥PFC, 功率因数校正, 升压电路, 平均电流控制
Abstract: Switching power supply and other power electronic devices are widely used in power systems, industrial, household, etc., in the benefit of mankind and also produced a harmonic problems can not be ignored. In order to suppress the amplitude of the current pulse, so that the switching power supply input current harmonics meet the requirement, thus the introduction of the power factor correction technology. This paper describes several general applied to an active power factor correction main circuit topology and elaborated on the relevant control strategies, analyzes the basic bridgeless PFC power factor correction circuit theory, and then proposed based on the average current improved control chip UC3854 bridgeless PFC converter. Finally, the selection of parameters for the calculation BOOST inductance calculations, the calculation of the output filter capacitor, the maximum input power and the input current and the selection of the input capacitance and switching devices designed main circuit and control circuit is designed using UC3854, using TLP250 drive circuit chip design, using a sampling resistor designed sampling circuit protection circuit uses a common limited pressure limiting way to achieve the design of the circuit.
Keywords: Bridgeless PFC, power factor correction, boost circuit, average current control
目录
1 绪论 4
2功率因数校正 4
2.1 功率因数的定义 5
2.2功率因数校正技术的发展及分类 5
3功率因数校正主电路的拓扑及控制策略分析 7
3.1 PFC主电路拓扑 7
3.2常见的APFC电路的控制策略分析 8
4 BOOST PFC电路原理分析 9
4.1基本的无桥BOOST PFC的工作原理 9
4.2改进型无桥BOOST PFC的工作原理 11
5改进型BOOST PFC电路设计 13
5.1主电路设计 13
5.2控制芯片UC3854 16
5.3驱动电路设计 18
5.4采样电路设计 19
5.5保护电路设计 20
结语 21
参考文献 22
致谢 23
1 绪论
20世纪80年代以来,随着电力电子技术的快速发展,各种电力电子装置在工业、电力系统、交通、家庭等众多领域中应用广泛,由此带来的无功(Reactive power)和谐波(Harmonics)[4]问题日益严重。