单相单级全桥PFC变换器关键技术研究

发布时间：2018-02-24 14:17

本文关键词： 单级全桥功率因数校正电压尖峰输出电压纹波预测控制　出处：《哈尔滨工业大学》2016年硕士论文　论文类型：学位论文

【摘要】：为了抑制谐波对电网造成的污染、提高变换器功率因数,功率因数校正(Power Factor Correction,PFC)技术开始被人们所关注并使用。其中单级式APFC因具有结构简单、成本较低、效率较高等优势成为了当前的研究热点,本文对单级全桥PFC变换器存在的桥臂电压尖峰、输出电压纹波问题及相关技术进行了研究。单级全桥PFC变换器由于变压器原边漏感的存在,在电路换流过程中会产生较大的桥臂电压尖峰,增大了开关管的电压应力。为此结合有源箝位技术,提出一种基于有源箝位辅助环节(Active Clamp Auxiliary Link,ACAL)的桥臂电压尖峰抑制方法;利用箝位电容来吸收桥臂电压尖峰,箝位电容上的能量通过隔离DC/DC变换电路释放到负载侧。采用PSIM软件进行了仿真分析,结果表明,该方法具有很好的电压尖峰抑制效果。单级PFC变换器因使用一级电路同时实现PFC和DC/DC变换,导致在输出侧存在较大的2倍工频电压纹波,影响系统的输出特性。为解决这一问题,利用基于ACAL的单级全桥PFC变换器,提出一种利用ACAL中箝位电容吸收的能量,来抑制输出电压2倍工频纹波的方法,并设计了输出电压2倍工频纹波的提取方法和相应的实现方案。采用Simulink软件进行了仿真分析,结果表明,该方法可以在不影响系统功率因数校正的前提下降低输出电压纹波。预测算法具有运算量小、结构简单的优点,在介绍预测算法工作原理的基础上,通过分析电压环对PFC预测算法的影响,提出一种具有快速动态响应能力的改进预测控制算法,来实现变换器PFC功能和快速动态响应能力。通过Simulink软件对算法进行了仿真分析,结果表明该算法具有良好的控制性能。最后,在硬件电路平台上进行了实验验证,结果表明所提方法可以在不影响系统PFC功能和快速动态响应能力的前提下,可以有效地抑制桥臂电压尖峰和输出电压纹波。
[Abstract]:In order to restrain the harmonic pollution to the power network and improve the power factor of the converter, the power factor correction Factor correction (PFC) technology has been paid more attention to and used. Among them, the single-stage APFC has simple structure and low cost. The advantages of high efficiency have become the focus of current research. In this paper, the voltage spike of single stage full-bridge PFC converter is discussed. The ripple problem of output voltage and the related technology are studied. Because of the leakage inductance of transformer, the voltage spike of the bridge arm will be produced in the converter of single-stage full-bridge PFC converter. The voltage stress of the switch tube is increased. A voltage spike suppression method based on active Clamp Auxiliary link is proposed to absorb the voltage spike of the bridge arm, which is based on the active clamp technique. The energy on the clamping capacitor is released to the load side by isolating the DC/DC transform circuit. The simulation analysis is carried out by using the PSIM software. The results show that, This method has a good effect on the suppression of voltage spike. Single stage PFC converter uses one stage circuit to realize PFC and DC/DC transform at the same time, which leads to the existence of 2 times power frequency voltage ripple at the output side. The output characteristics of the system are affected. In order to solve this problem, a method of suppressing the output voltage 2 times power frequency ripple by using the energy absorbed by the clamping capacitor in the ACAL is proposed by using the single-stage full-bridge PFC converter based on ACAL. The extraction method of output voltage 2 times power frequency ripple and the corresponding realization scheme are designed. The simulation analysis is carried out by using Simulink software, and the results show that, This method can reduce the output voltage ripple without affecting the power factor correction of the system. The prediction algorithm has the advantages of small computation and simple structure. By analyzing the influence of voltage loop on PFC prediction algorithm, an improved predictive control algorithm with fast dynamic response ability is proposed to realize the PFC function and fast dynamic response of converter. The algorithm is simulated by Simulink software. The results show that the algorithm has good control performance. Finally, the experimental results on the hardware circuit platform show that the proposed method can not affect the system PFC function and the ability of fast dynamic response. It can effectively suppress the voltage spike and output voltage ripple of the bridge arm.
【学位授予单位】：哈尔滨工业大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：TM46

【相似文献】