2.2PWM开关电源-世纪电源网.doc

班 班 级 020611 学 学 号 本科毕业设计论文 题 目： 市电LED驱动电源技术 学 院： 电子工程学院 专 业： 电子信息工程 学生姓名： 柴 威 荣 导师姓名： 王昌明 吕宁 摘 要 随着能源的日益短缺，低碳经济已成为人类共同的目标，LED绿色照明技术正是低碳经济的关键技术之一。LED照明具有节能、高效、环保、寿命长的特点，是取代白炽灯和荧光灯等传统照明灯具的最佳途径。 但是LED不能直接接入交流电网，需要专用的驱动电源，如何设计好的LED驱动电源成为LED未来发展的关键技术之一。 本文针对市电LED驱动电源技术，从分析LED特性入手，综合分析了LED需要专用的驱动电源的技术需求，进而提出了市电LED驱动电源的设计方案，包括选取开关电源集成芯片，变压器的设计，输入整流滤波、芯片供电、输出整流滤波及反馈网络等电路的设计，选取相应元器件，制作样机，并对样机进行测试。 论文采用PWM控制开关电源技术实现驱动电源的设计，要求在输入交流电压50—255V的条件下，空载输出直流电压范围在42—43V之间，负载时输出直流电流范围540—560mA，输出电流稳定，电源调整率在5‰以内。实验验证表明，该方案设计的驱动电源达到了设计要求。 关键词：LED驱动电源 PWM开关电源 稳流 ABSTRACT Nowadays, low carbon economy draw more and more people’s attention because of the crisis of energy shortage. LED green lighting technology has been one of the key technology of the low carbon economy. And LED lighting is the best way to replace incandescent and fluorescent lamp for its high efficient energy conservation and long-life. But different from incandescent, LED need special driver power supply, it can’t work under traditional AC network. So how to design a good LED driver power supply will be the key point in the development of the LED industry. This article is based on the power cable driver technology of LED, start analyzing of the characteristics of LED. Then put forward the technical requirements of LED driving power. And then it come up with the design proposal of the LED driving power, including how to choose the switch mode power supplies chip, designing the transformer and circuit of each part the chip, choosing device, making PCB, and testing the drive power supply prototype. At last, the experiments indicate that the driving power can fully satisfy the technical requirement under this scheme. The LED driving power supply ask for pwm switch mode power supplies technology to accomplish the power design which has the 42-43VDC voltage output without load and 540-560mA DC current output with loa