基于半桥电路的48V3A电动自行车充电器设计

基于半桥电路的48V/3A电动自行车充电器设计

摘要

在如今这个提倡绿色可持续发展的社会，因为电动自行车的广泛应用，其充电器的市场也越来越大，性价比高的电动车充电器在这个大舞台上，是很有竞争力的。所以我们根据半桥电路的特点设计了一个48V/3A的电动自行车充电器。这个充电器是根据电流模式的开关电源原理而设计的，其主电路采用了半桥电路，控制电路以SG3525芯片为核心，驱动电路使用IR2104为核心，结合稳压器等芯片，实现了对蓄电池的充电和控制，以达到在充电时对蓄电池进行保护的目的。本设计中介绍了使用到的相关的芯片，而且给出了完整的电路图，具体地分析了主电路的工作原理、各部分电路的工作原理和各种相关芯片的介绍，这其中包括了主电路、控制电路、驱动电路和电压、电流反馈电路的工作原理。并且还使用了MATLAB进行仿真，结果表明，该电动车充电器性能优良，能较好的保护蓄电池，稳定性非常强，而且成本比较低，非常有前景。

关键词：半桥电路，SG3525，电流模式，充电器

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DESIGNOF 48V/3A

ELECTRICBICYCLECHARGERBASEDONHALFBRIDGECI

RCUITFOR 48V/3A

ELECTEICBICYCLECHARGERBASEDONHALFBRIDGECI

RCUIT

ABSTRACT

In this advocate green and sustainable development of the society, because of the widespread use of electric bicycle charger, the market is more and more big, high performance electric car charger in this big stage, is very competitive. So we design a 48V/3A electric bicycle charger based on half bridge circuit. This charger is designed according to the principle of the current mode switching power supply, the main circuit adopts half bridge circuit, the control circuit based on SG3525 chip as the core, drive circuit using IR2104 as the core, combined with the regulator chip, realizes the charging and control of the battery, in order to protect the battery during charging to. This design describes the use of related chips, and presents the design of integrated circuit, a detailed analysis of the working principle and circuit design, each part of the circuit chip is introduced, including the working principle of the main circuit, control circuit, drive circuit and voltage and current feedback circuit. The simulation results show that the charger has good performance and can protect the storage battery better. The stability of the MATLAB charger is very strong, and the cost is low. It is very promising.

KEYWARDS：The half bridge circuit, SG3525, current mode ,charger

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目录

1绪论 .............................................................. 5 1.1 研究背景 ...................................................... 5 1.2 研究现状 ...................................................... 5 1.3 充电器的结构与分类 ............................................ 6 1.3.1 充电器的分类 .............................................. 6 1.3.2 充电器的结构 .............................................. 7 1.4 本文设计内容及要求 ............................................ 7 1.4.1设计内容 .................................................. 7 1.4.2设计要求 .................................................. 7 2电动车自行车蓄电池及其充电方式介绍 ................................ 9 2.1 电动车的蓄电池 ................................................ 9 2.2 电动车蓄电池充电方式 .......................................... 9 2.2.1 恒流充电 .................................................. 9 2.2.2 恒压充电 ................................................. 10 2.2.3 浮充法 ................................................... 11 2.2.4 涓流充电 ................................................. 11 2.3 分阶段充电法 ................................................. 12 3芯片和电路原理介绍 ............................................... 14 3.1芯片介绍 ..................................................... 14 3.1.1 SG3525芯片 .............................................. 14 3.1.2 IR2104芯片 ............................................... 16 3.1.3 TL341芯片 ............................................... 17 3.2电路原理介绍 ................................................. 20 3.2.1主电路电路原理 ........................................... 20 3.2.2 整流电路 ................................................. 21 3.2.3 滤波电路 ................................................. 22 3.2.4 半桥电路 ................................................. 24 3.2.5 半桥电路的驱动电路 ....................................... 25 3.2.6电压反馈电路 ............................................. 25 3.2.7 电流反馈电路 ............................................. 26 3.2.8辅助供电电路 ............................................. 27

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4变压器的选择和元器件参数计算 ..................................... 28 4.1变压器的设计 ................................................. 28 4.2 输出滤波电感选择 ............................................. 30 4.3 SG3525确定频率的电容和电阻参数计算 .......................... 30 4.4 SG3525的软启动电阻说明 ...................................... 31 4.5 输入输出滤波电容选择 ......................................... 31 4.5.1输入滤波电容选择 ......................................... 31 4.5.2输出滤波电容选择 ......................................... 31 4.6 一次侧整流二极管的选择 ....................................... 31 4.7 开关管、续流二级管和二次侧整流二极管的选择 ................... 32 5 MATLAB仿真 ..................................................... 34 6结论 ............................................................. 37 致谢............................................................... 38

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