excitationsström

An excitationsström, or excitation current, refers to the flow of electrical current used to create a magnetic field in devices like transformers, electric motors, and generators. This current is distinct from the load current, which is the current that flows through the secondary winding or the working part of the device to deliver power to a load. The excitationsström is essential for the fundamental operation of these electromagnetic devices as it establishes the magnetic flux that links the windings and enables energy transfer or conversion.

In a transformer, the excitationsström flows through the primary winding when a voltage is applied. This current produces the magnetic flux in the core, which then induces a voltage in the secondary winding. The magnitude of the excitationsström is typically small compared to the full load current and is primarily determined by the inductance of the primary winding and the applied voltage. It is often referred to as the magnetizing current.

Similarly, in electric motors and generators, excitationsström is crucial for generating the magnetic field. In DC machines, it flows through field windings. In AC machines like induction motors, it's a component of the stator current that creates the rotating magnetic field. This current is responsible for magnetizing the rotor or stator, depending on the machine's design, and is vital for torque production or voltage generation. The characteristics of the excitationsström influence the efficiency and performance of these electrical machines.