mätspolar

Mätspolar, also known as measuring coils or Rogowski coils, are a type of current transformer used to measure alternating current (AC) and transient currents. Unlike traditional current transformers that require a direct connection in series with the conductor, mätspolar are non-contact sensors, offering significant advantages in certain applications.

The core principle of a mätspolar involves a flexible coil wrapped around the conductor carrying the current to be measured. As the AC current flows through the conductor, it generates a changing magnetic field. This changing magnetic field induces a voltage in the mätspolar coil. The magnitude of this induced voltage is directly proportional to the rate of change of the current, not the current itself.

To obtain a direct reading of the current, the induced voltage from the mätspolar is typically passed through an electronic integrator circuit. This integrator converts the rate of change of current (di/dt) into a voltage signal that is proportional to the instantaneous current (i). This makes mätspolar suitable for measuring both steady-state AC currents and fast transient current pulses.

Key advantages of mätspolar include their flexibility, light weight, and ability to be easily installed around existing conductors without disconnecting them. They are also ideal for measuring high currents and in environments where safety is a concern, as they provide electrical isolation. Applications range from power monitoring and protection systems in industrial settings to transient current analysis in research and development.