通过脉冲信号控制buck变换器实现降压，通过傅里叶函数得到平均值。(The buck converter is controlled by the pulse signal to achieve the depressurization, and the average value is obtained by the Fourier function.)

建立了开环的BUCK电路模型，并分别以不同参数模拟了DCM和CCM模式下的buck模型。(An open loop BUCK circuit model is established, and buck models under DCM and CCM modes are simulated with different parameters.)