Transformatorkobling

Transformatorkobling refers to the way transformer windings are connected to each other. The specific configuration of these connections, known as the winding arrangement or vector group, dictates the phase relationship between the primary and secondary voltages and currents. Common transformer kobling arrangements include Delta (D), Star (Y), and Zigzag (Z).

In a Delta connection, the ends of each winding are connected to the beginning of the next, forming a closed triangle. This arrangement offers advantages such as higher starting torque for motors and the ability to continue operation at reduced capacity if one winding fails. A Star connection involves connecting one end of each winding together to form a neutral point, with the other ends serving as line terminals. This configuration provides a neutral point, which is essential for single-phase loads and grounding. The Zigzag connection is a variation of the Star connection where the windings are connected in a broken delta or zigzag pattern, often used to mitigate harmonics and balance phase currents in unbalanced systems.

The choice of transformer kobling is crucial and depends on factors such as the required voltage levels, the nature of the loads, system grounding requirements, and the need for harmonic suppression or fault current limitation. Different kobling combinations, such as Dyn1, Yyn0, or Dzn11, denote specific phase shifts and vector group designations, which are critical for parallel operation of transformers and for maintaining correct phase relationships in power systems.