A Current-Sensing Method for Integrated Transformer

作者：Jin Ke^*; Gu Ling; Sun Yi; Xu Ming

来源：IEEE Transactions on Power Electronics, 2012, 27(3): 1061-1065.

DOI：10.1109/TPEL.2011.2169430

• Current sensing
• integrated transformer
• voltage regulator module (VRM)

Current-sensing circuit is critical for dc-dc converter to achieve current mode control, current protection, and current sharing. Moreover, for voltage regulator module (VRM) applications, the inductor current needs to be sensed for adaptive voltage positioning. A high-frequency, self-driven full-bridge-type VRM has been recently proposed for high efficiency with integrated transformer. However, the existing current-sensing methods are unsuitable for integrated transformer. To solve this problem, this letter proposes a novel current-sensing method for VRMs with integrated transformer. A well-designed capacitor-resistor-sensing network is employed in parallel with the transformer's secondary side, and then the voltage across the capacitor is sensed to monitor the transformer magnetizing inductor current instantaneously. This method is accurate, lossless, and simple in structure. A 1.2-V/130-A output voltage regulator module is built in the laboratory to verify the proposed method.

• 出版日期2012-3
• 单位南京航空航天大学