Research on a Fourier analysis of high-power non-bridge LED drive circuit in the illumi-nation use, introduced by the authors, is carried out. Under the given circuit condition, the con-tent of its frequency spectrum and harmonic was analyzed and calculated. The result shows that there almost exists no harmonic in the frequency range below the lowest working frequency of the circuit. THD, the content of the total harmonic of the circuit input current, rises with increase of the minimum input current pulse width T_0_((min)) and lowers with the increase of the effective value ratio of circuit output direct voltage and input alternating voltage U_o/U_i. It indicates that a filter circuit is needed at the input port of the circuit and its filtering effect was analyzed. The design method of the filter circuit is also provided.%对作者介绍的照明用大功率无桥LED驱动电路的输入交流工频电流波形在设定电路条件后的频谱和谐波含量进行了分析和计算,其结果是,在电路最低工作频率以下的频率范围内基本不存在谐波成分,电路输入电流的总谐波含量THD随最小输入电流脉冲宽度T_0_((min))增大而上升,随电路的输出直流电压与输入交流电压有效值的比U_o/U_i的增大而下降.并指出在电路的输入端需要一个滤波电路,分析了滤波电路的滤波效果,给出了滤波电路的设计方法.
展开▼
