基于有源闭环控制技术的高性能开关电源设计

Design of switching power supply with high performance based on active and closed-loop control technique

在一般非线性系统有源控制技术的基础上，用同步整流反激式（Flyback）DC／DC变换器作为主电路，采取双闭环控制、降低功耗和抑制谐波的措施，设计一款有源功率因数校正（APFC）开关电源整机系统，并进行样机试验。试验结果表明，APFC开关电源能够正常稳压，功率因数达到0．932—0．999，接近于单位功率因数，整个电源系统的效率达到85．8％—88．7％，高频纹波电压约为3V，低频100Hz时纹波电压约为9．8V，且谐波电压总畸变率小于3．65％，谐波污染程度较低，因此这款“绿色电源”特别适用于各种中小型功率设备。

On the basis of active control technology in non-linear system, a sync rectifier Flyback DC/DC converter was taken as the main circuit. A series of effective measures of dual closed-loop control to reduce the power consumption and restrain the harmonic components were adopted. A kind of APFC switching power supply was designed. Several circuit experiments were carried out. The experimental results show that the operation of the designed APFC supply is stable, and its power factor reaches 0. 932 - 0. 999 with the supply working within the normal range, quite close to the unity power factor. Moreover, the efficiency of the whole supply reaches 85.8% - 88.7%, the output-ripple voltage of the supply is about 3 V at high-frequency and about 9.8 V at low-frequency 100 Hz. The total harmonic voltage distortion is below 3. 65%, reaching the level of lower harmonic pollution. With these characteristics, the designed APFC switching power supply is especially suitable for the ＂green power supply＂ of the middle and small power installations.