简易数字控制开关电源设计与实现

Design and implementation of simple and digital control switch power supply

设计了一种基于微处理器(MSP430G2553)的简易数字控制开关电源。电源系统主电路采用单端反激式变换器,控制电路采用PWM调制方式控制TLP250进行隔离驱动。整个电源系统通过PID算法对系统进行闭环控制,可实现输出电压稳定可调。系统硬件电路设计包括前级保护电路、整流桥电路、反激式功率变压器、驱动电路、控制环路以及输出滤波电路设计等。在完成整个系统的软硬件设计后,整个系统各项性能指标都通过了测试。系统可实现输出电压5 V^20 V可调,输出电压误差小于5%,效率高于75%,负载调整小于3%,最大输出纹波电压为84 mV,并且具有过压保护、界面显示等功能。

A simple and digital control switch power supply based on microprocessor（ MSP430G2553） is designed. The main circuit of the power system uses single ended flyback converter,and the control circuit uses PWM modulation mode to control the TLP250 to isolate the driver. The whole power system is controlled by PID algorithm for closed loop controlling,and can realize the output voltage to be stable adjustable. The design of system hardware circuit includes the former level protection circuit,rectifier bridge circuit,flyback power transformer,drive circuit,control circuit and output filter circuit design,etc. After completing the software and hardware design of the whole system,the performance index of the whole system has passed the test. The system can realize the output voltage that can be adjusted from 5 V to 20 V,output voltage error is less than 5%,efficiency is higher than 75%,load adjustment is less than 3%,the maximum output ripple voltage is 84 mV,and has over-voltage protection,as well as interface display and other functions.