多芯电缆微弱磁场能量采集器的高效管理电路

Efficient and low power consumption management circuit of energy harvester for weak magnetic field around multi-core cables

现有磁场能量采集器标准能量管理电路效率低、功耗高、输入阈值功率高,在换能器采集较弱磁场能量时,难以驱动多芯电缆监测系统。针对上述问题,本文提出了一种间歇充放电的低功耗多芯电缆微弱磁场能量采集管理电路方案,设计了自供电的低功耗间歇控制电路,大幅度降低功耗。该电路通过自供电变频匹配,提高管理电路的能量转换效率。实验结果表明,当三芯电缆通过40 A、50 Hz的交流电时,磁场能量采集器输出功率为3.3 mW,管理电路的最大输出功率可达2.45 mW,最大效率74.24%,较标准能量采集管理电路提升了6.9倍。所提出的超低功耗自供电控制电路,满足启动阈值的最小平均功耗仅为1.52μW,仅为带辅助电源的控制电路功耗的5.93%。该高效管理电路不仅可以用于多芯电缆微弱能量采集,还可以用于由于铠装屏蔽导致的微弱电缆周边磁场、电磁振动能量采集器、反向散射传感器网络等微弱感性磁场能量管理。

The existing magnetic field energy collector standard energy management circuit has advantages of low efficiency,high power consumption,and high input threshold power.When the transformer collects weak magnetic field energy,it is difficult to drive the multi-core cable monitoring system.To address the above issues,this article proposes a low-power and multi-core cable weak magnetic field energy collection management circuit principle of intermittently charging discharge.A low-power intermittent control circuit for self-powered power supply is designed to greatly reduce power consumption.This circuit is comparable to the energy conversion efficiency of the management circuit through self-power supply variable frequency matching.The experimental results show that when the three-core cable passes the AC power of 40 A and 50 Hz,the output power of the magnetic field energy collector is 3.3 mW,the maximum output power of the management circuit can reach 2.45 mW,the maximum efficiency is 74.24%,which is higher than the standard energy collection management circuit 6.9 times.The proposed high-power self-power supply control circuit to meet the minimum average power consumption of the startup threshold is only 1.52μW,which is only 5.93%of the control circuit power consumption with auxiliary power supply.This high-efficiency management circuit can be used not only for the weak energy collection of multi-core cables,but also for weak emotional magnetic field energy management such as the weak cable peripheral magnetic field,electromagnetic vibration energy collector,and reverse scattering sensor network caused by armor shielding.