用于电磁能量收集的单级同步开关接口电路以提升功率与稳压性能

Synchronized switch interface circuits demonstrate good performance for electromagnetic energy harvesting applications, but lack adaptability in terms of harvested power. This article introduces an additional control degree of freedom by proposing two power control methods and implementing them in a synchronous current inversion and energy extraction (SCIEE) circuit. Theoretical analysis indicates that the single-stage system achieves higher efficiency for approximately 41.3% of the supported load range compared to using a commercial dc–dc regulator. In the load transient experiments, the proposed system maintains the output voltage well-regulated, with undershoot and overshoot below 0.2 V. The output voltage ripple is 0.15 V at an 18 mA load current. The proposed system is compared to three other options: a direct ac–dc harvesting circuit, the synchronous switch energy extraction (SSEE) circuit, and a two-stage harvesting system using a commercial dc–dc regulator and an open-loop SCIEE circuit. The proposed system supports a maximum load current of 29.47 mA, the highest among these options. In a field test, the proposed system supports successful integrated circuit long range (LoRa) packet transmissions and exhibits a broader supported load range than the SSEE or direct ac–dc harvest scheme.