The Rogowski Coil is a sensor used for the measurement of the current. This class of coils achieves very good results even for currents with a large variation range. However, they generate an output signal in the time-differentiated form. In this case, an integrator function (available in the Microchip metrology library running in Core 1) must be added to get the corresponding current value.
Figure 1. IPx and INx Current Sense
Schematic when Using Rogowski Coil
When using Rogowski coils for current sensing, a two pole anti-aliasing filter must be
mounted. The filter must be tuned with the following component values:
- RA1, RA2 = Do Not Populate
- RB1, RB2 = 100Ω, 1%, 25 ppm/ºC
- RC1, RC2 = 3 kΩ, 1%, 25 ppm/ºC
- CA1, CA2 = 47 pF Y7R
- CB1, CB2 = 2.2 nF NP0/COG
- CC1, CC2 = 3.3 nF NP0/COG
- D1, D2 = Si Junction diodes (recommended)