摘要由于电力电子器件优势明显,近年来它们在各行各业中得到了广泛的应用。然而也带来了诸如对电网侧造成谐波污染和低功率因数的负面问题。随着各种标准的出台,越来越多的国家对功率因数校正和降低谐波电流提出了强制性要求。因此,功率因数校正(PFC)技术成为了一个重要的研究方向。数字控制技术的成熟发展,使PFC的控制策略能通过数字信号处理器实现。数字控制方案能实现复杂的算法而且灵活方便,相对于模拟控制优势明显,因此引起了研究人员的广泛关注。 本文主要介绍了一种临界导电模式的功率因数校正电路,并将它与 DSP芯片MC56F8023相结合设计了一台输出400V,功率等级 80W的PFC样机,实现了数字化控制方案。论文内容包括:认真研究了功率因数校正技术的原理,选择临界导电模式的PFC技术;详细分析了临界导电模式 PFC电路的工作原理;结合文献资料推导得到主电路中电感等元器件的参数;分析比较临界导电模式的两种控制方案,选择不带乘法器的控制方案;设计了样机的各个模块,包括供电电源、EMI电路、主电路、控制回路中的软件编程和芯片的外围电路等;在数字化控制方案中学习了DSP芯片 MC56F8023的工作原理,尤其是该电路设计用到的 PWM模块、ADC(模数转换)模块和中断工作流程;在code warrior中编写了控制回路的主程序和中断程序。文章的最后,通过软件仿真和实验调试,对所设计的样机进行了测试,验证了理论分析的正确性。60991
毕业论文关键词 数字化控制 临界导通模式 功率因数校正
Title A Design of Digital Power Factor Correction Circuit
Abstract Power electronic devices have been widely applied to in all kinds of fields due to their obvious advantages. However, it also causes negative problem, such as harmonic pollution in the grid and low power factor. With the introduction of various standards, mandatory requirements are put forward by more and more countries for power factor correction and the decrease of harmonic current. Therefore, the power factor correction (PFC) technology has become an important direction in the research. Along with the development of digital control technology, more and more of the PFC control strategy can be achieved via a digital signal processor (DSP). Complex algorithms can be implemented by digital control scheme in a flexible way, which makes digital control aroused widespread concern. A critical conduction mode (CRM)of the power factor correction circuit which realizes digital control scheme by combining it with the DSP chip MC56F8023 is introduced in this paper. A 400V/80W experimental prototype is designed. The Paper includes the following contents, the study of the principle of PFC, a CRM PFC circuit being selected, detailed analysis of the CRM PFC circuit working, getting the parameters of the components in the main circuit such as the inductor, analyzing and comparing two control schemes, the control scheme with no multipliers is selected, each module of the prototype including EMI circuit, the power supply, the main circuit and the control circuit is designed, the study of the DSP chip MC56F8023 especially the PWM module, the ADC module and the interrupt module . At the end of the paper, the prototype designed is tested through software simulation and experimental to verify the theoretical of the analysis.
Keywords Digital control Critical conduction mode Power factor correction
目次
1绪论.1
1.1研究背景...1
1.2PFC技术分类和发展.2
1.3PFC的数字方案分析.4
1.4本文的研究内容.5