电力电子变换器级联系统阻抗全系统算法

Input-output impedance computing method for whole system of cascaded power electronic devices

电力电子变换器级联系统静态稳定性分析一般采用Middlebrook阻抗判据,运用该方法的关键是输入输出阻抗的计算。由于传统计算方法必须建立系统的小信号等效电路模型,难以解决复杂电力电子系统的阻抗计算难题。因此,首先提出了电力电子变换器级联系统端口处的数学描述方法,然后在此基础上,提出了全系统输入输出阻抗计算方法,并通过实例与传统计算方法的结果进行了比较,验证了该算法的正确性。

Generally, the impedance criterion is adopted to analyze the static stability of the electronic cascaded system. So, impedance computation is the key to the impedance criterion method. The tradi- tional computing method based on the small-signal equivalent circuit model cannot cope with difficul- ties in computation of the complicated power system with electronic devices. For the reason, this pa- per proposes a method of mathematic description of the electronic cascaded system and further an input-output impedance computation method for the whole system. The results of comparing this method and the traditional method verify that the method proposed is feasible and effective.