What Is a Rogowski Coil?

Rogowski Coil is also called Rokowski Coil, Rogowski Coil or Air Coil.

Rogowski coil

Rogowski coil is a kind of hollow loop coil. It has two types: flexible and rigid. It can be directly placed on the conductor to be measured to measure AC current. The basic principle of its design is shown in the figure:

1. It has unique advantages for high frequency and high current measurement;

2. Good linearity and easy calibration, but when measuring non-sinusoidal current or unknown frequency current, you need to configure the integrator to use;

3. Can measure irregular conductors;

4. Easy installation without destroying the conductor;

5. Applicable frequency from 0.1Hz to 1MHz;

6. Low high-frequency angular difference, large low-frequency angular difference;

7. No secondary open circuit danger;

8. Simple and convenient maintenance;

Integrator and secondary instrument (2 photos)

In addition to the standard sine wave with a fixed and known frequency, the Rogowski coil needs to be used with an integrator when measuring. Because Rogowski coils are usually used to measure high-frequency currents or large currents, the measurement environment has large electromagnetic interference, which requires special attention when measuring. In order to reduce the influence of interference, a digital output integrator is preferred.

The digital output integrator completes the integration of the output voltage signal of Rogowski coil and AD sampling inside the integrator, and uploads the AD sampling result to the secondary instrument or host computer using optical fiber as the medium. Can effectively avoid loss and interference during transmission. When using, pay attention to the analog connection between the integrator and Rogowski coil as short as possible, and use shielded wire as much as possible.