单相AC-DC转换电路精要.doc

2013 年全国大学生电子设计竞赛单相AC-DC变换电路(A题)

【本科组】

单相AC-DC变换电路

摘要：本系统基于有源功率因数校正(PFC)芯片UCC28019及单片机AT90C516，设计并制作了单相AC-DC变换电路。系统电路主要包括六个模块：变压器模块、功率因数校正模块、过流保护和报警模块、相位测量模块、单片机显示和控制模块、辅助电源模块。变压器由自耦变压器和隔离变压器构成，可实现20~30V可调的交流电压；功率因数校正模块通过UCC28019芯片内部电压和电流双闭环控制实现输出直流电压36V，最大输出电流可达到2.5A；过流保护模块采集输出电流，当电流超过2.5A，单片机控制继电器关断电源，以达到断电的目的，同时报警电路提示；相位测量模块采集输入端的电压、电流，经过零检测和A/D转换，至单片机AT90C516显示。辅助电源模块为UCC28019、单片机提供电源。测试表明，本文设计的单相AC-DC变换电路可实现输入功率为37.5W，输出功率为30W，效率为80%，功率因数为0.98，很好地实现了本次竞赛“单相AC-DC变换电路”的各项指标，具有良好的人机界面。

关键词：AC-DC；功率因数；相位

Abstract: The system is base on UCC28019 which is an active power factor connection chip and MCU AT90C516, in order to design single-phase AC-DC conversion circuit. The system has six modules including a transformer module、PFC module、an overcurrent protection and alarm module、a phase measuring module 、a MCU module which is used to measure and display and an auxiliary supply power module. The transformer module is consisted of an autotransformer and an isolation transformer, it can output a volage ranged from 20V to 30V. The PFC module is based on UCC28019, it is able to output 36V and maximum current 2.5A. The overcurrent protection module collect output current 2.5A, when the current is over2.5A, the MCU will control the relay to cut off the power, the alarm circuit will give a hint at the same time. The phase measuring module collect input volage and input current, after zero-cross detection and A/D conversion. The AT90C516 will display the results. The auxiliary supply power module is used to providing volage to the chips. According to the measurement, the input power is 37.5W,the output power is 30W,the efficiency is 80%,the PFC is 0.98, it complete the indexes perfectly, and has a good man-machine interface.

Keyword: AC-DC; PFC; phase;

目录

一． 2

1．PFC校正电路2

2．相位测量电路3

3．过流保护3

二．理论分析与计算4

1．PFC控制电路的参数计算4

2．相位测量电路的参数计算5

三．电路与程序设计5

1．硬件电路设计5

2．软件设计8

四．测量方案与测试结果9

1．功率因数测量的方案9

2．测量仪器及测量方法10

3．测量数据11

五、总结13

六、 参考文献13

附录14

一、设计任务14

1、任务