1.4kW数字化开关电源整机系统设计与实现

发布时间：2018-09-05 21:19

【摘要】：随着数字化控制策略和现代电力电子技术的飞速发展,开关电源的数字化实现逐渐成为现代电源技术的一个热点课题研究方向。本文选以前级交错并联Boost PFC拓扑与后级移相全桥DC/DC拓扑联合的开关电源作为数字化实现的研究对象,基于UCD3138数字电源控制芯片,实现Boost PFC、DC/DC在数字化控制系统中的结合,提高电源的稳定性、可靠性、智能化。本文具体研究工作概括如下:首先,对交错并联Boost PFC变换器和移相全桥软开关DC/DC变换器的工作原理进行了详细分析,建立了前级和后级的小信号模型,得出了相应的传递函数。对前级的数字化控制方式进行比较,选取了基于数字芯片控制的平均电流法,并针对两相支路电流不平衡给出了相应的控制策略。分析了后级占空比丢失现象和软开关技术的实现条件,给出了相应的控制策略。其次,根据数字化开关电源设计要求和电路工作特性,确定了主电路和辅助电路的主要器件参数。设计了前级和后级的数字控制器,结合变换器的小信号模型,利用Matlab工具绘制出开环Bode图,验证理论分析结果。通过对前后级电路的仿真分析,进一步验证系统控制策略的合理性并得出结论。最后,研制出一台1.4kW的全数字化开关电源样机,前级和后级均由数字电源芯片UCD3138控制。建立了基于Labview的可视化操作界面,实现输入输出状态监测,故障监视与报警,零载睡眠及唤醒控制,使得开关电源的控制更加简洁、高效。实验结果表明,电源前级电流纹波在合理范围内,功率因数符合设计要求,电源后级软开关技术得到了很好的实现,输出电压纹波在合理范围内,带载能力符合设计要求,电源整机系统在全负载范围内均能够稳定运行。
[Abstract]:With the rapid development of digital control strategy and modern power electronic technology, the digital realization of switching power supply has gradually become a hot topic of modern power supply technology. Based on UCD3138 digital power control chip, the combination of Boost PFC and DC/DC in digital control system is realized to improve the stability, reliability and intelligence of power supply. The small signal models of the front stage and the back stage are given, and the corresponding transfer functions are obtained. Compared with the digital control methods of the front stage, the average current method based on the digital chip control is selected, and the corresponding control strategy is given for the unbalanced current of two-phase branch. The phenomenon of duty cycle loss in the back stage and the realization of soft-switching technology are analyzed. Secondly, according to the design requirements of digital switching power supply and the working characteristics of the circuit, the main device parameters of the main circuit and the auxiliary circuit are determined. Finally, a 1.4 kW full-digital switching power supply prototype is developed. Both the front and rear stages are controlled by the digital power supply chip UCD3138. A visual operation interface based on Labview is established to monitor the input and output states. Fault monitoring and alarm, zero-load sleep and wake-up control make the control of switching power supply more simple and efficient. The experimental results show that the power factor meets the design requirements within a reasonable range of current ripple at the front stage of the power supply, the soft-switching technology at the back stage of the power supply is well realized, the output voltage ripple within a reasonable range, and the load-carrying capacity meets the requirements. Design requirements, the power supply system can operate stably in the full load range.
【学位授予单位】：华侨大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TM46;TN86

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