Abstract：Impedance measurement is very important in power electronic based systems because of the close relationship between impedance and stability. However, traditional frequency sweep method always selects the equal frequency interval without guiding theory, which results in low accuracy, low reliability and low efficiency. In this paper, the relationship between measured result and the frequency interval is built firstly, then a segmented binary tree method for power electronic system impedance measurement is proposed. With this method, injection frequency points can be selected automatically according to the requirement of measurement accuracy. Compared to the traditional frequency sweep method, the proposed one can measure impedance more accurately and efficiently. The experimental results validate the effectiveness of the proposed method.
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2015, Vol. 30 
