Title :
Advanced Four-Pair Architecture With Input Current Balance Function for Power Over Ethernet (PoE) System
Author :
Wu, Jiande ; Wu, Haimeng ; Li, Chushan ; Li, Wuhua ; He, Xiangning ; Xia, Changliang
Author_Institution :
Coll. of Electr. Eng., Zhejiang Univ., Hangzhou, China
Abstract :
In the typical Power over Ethernet (PoE) system, the conventional powered device (PD) with two-pair architecture can only provide power below 20 W to the distant loads, which greatly restricts its applications in many areas. An advanced type of four-pair architecture with an input current balance function for the PoE system is proposed in this paper to not only improve the power level, but also achieve the high conversion efficiency. The steady-state model of the four-pair architecture is built to explore the existing imbalance problem, which is mainly caused by the structure and impedance inconsistency. The proposed four-pair architecture consists of two main converter modules operated in parallel. An input current balance scheme is adopted to reduce the difference of both primary currents, which can increase the transmission power and improve the current sharing performance. Furthermore, the small-signal model of the paralleled converters with an input current balance control strategy is constructed to give a design guideline for the control loop. Finally, a 50-W prototype is built and tested to verify the effectiveness of the presented architecture and control strategy.
Keywords :
closed loop systems; electric current control; local area networks; power convertors; PoE system; advanced four-pair architecture; control loop; converter modules; current sharing performance; high conversion efficiency; input current balance control strategy; input current balance function; power 50 W; power over Ethernet system; powered device; primary currents; small-signal model; transmission power; two-pair architecture; Bridge circuits; DC-DC power converters; Power generation; Resistors; Steady-state; Stress; Topology; Active-clamp forward converter; Power over Ethernet (PoE); four-pair architecture; input current balance; powered device (PD);
Journal_Title :
Power Electronics, IEEE Transactions on
DOI :
10.1109/TPEL.2012.2214401