A high-sensitivity design method for Rogowski coils on stacked PCB

Rogowski coils made of printed circuit boards (PCB) are hard coils, with the advantages of uniform wire distribution, good parameter consistency, and small size compared with traditional Rogowski coils. Restricted by the PCB thickness fabrication process, the Rogowski coil fabricated by a single PCB board has low sensitivity due to its small thickness, and the output voltage is still very small when measuring larger currents. To improve the sensitivity of the PCB Rogowski coil and the mutual inductance coefficient between the coil and the conductor to be measured, a kind of Rogowski coil stacked with multiple PCBs of the same size is proposed. Different coil heights can be realized by stacking different numbers of PCBs, which improves the mutual inductance coefficient per unit volume of the PCB Rogowski coil. The electromagnetic parameters of the stacked PCB Rogowski coil were extracted, the circuit model was established to make theoretical calculations, and its finite element simulation model was established to make simulation analysis. Then, an experimental platform with low voltage and variable high current was built, and experiments were conducted. The experimental results show that the stacked PCB Rogowski coil performs well with high sensitivity and a large mutual inductance coefficient per unit volume.