基于DSP的单ADC数字功率因数校正器研究

Research on single ADC digital power factor corrector based on DSP

传统数字功率因数校正器要使用三路ADC采样,特别是电感电流的采样会造成电路效率的下降以及复杂度的上升。研制一台基于Boost电路的数字功率因数校正器,控制回路只使用了一路ADC采样平均输出电压以及输出电压纹波。开关管所需要的占空比值会预先计算好,采样的平均输出电压形成输出平均电压环,采样的输出电压纹波形成输出电压纹波环。两个环路分别对占空比相应的部分进行控制,保证了整个系统可以达到较好的功率因数校正效果。最后,采用TMS320F28335数字信号处理器作为控制芯片,实验结果验证了该方法的正确性。

Traditional digital power factor correction uses three analogtodigital converters.Each converter,especially forthe inductive current one,increases the cost and the complexity of the system.A digital power factor corrector based on Boost ispresented in this paper,in which only one ADC is used for control loop to sample the average output voltage and the ripple ofthe output voltage.The duty cycles that the switching tube needs are precalculated.The sampled average output voltage formsthe output average and the sampled output voltage ripple forms output voltage ripple loop.These two loops control the corresponding part of the duty cycle respectively,which makes the power factor correction effect of the whole system higher.TMS320F28335DSP is used as a control chip.The experiment results verified the correctness of the method.