Neutraaliliitännän

Neutraaliliitännän, often translated as neutral connection or neutral link, refers to a point in an electrical system where the neutral conductor is established. This point is typically grounded, providing a reference potential close to earth potential for the entire system. In a three-phase system, the neutral point is usually the junction of the three phase windings of a transformer or generator. This connection ensures that voltages between any phase conductor and the neutral are balanced when the system is under normal load.

The primary purpose of the neutral conductor is to carry the unbalanced current in a three-phase system. If the loads on each phase are perfectly balanced, no current flows through the neutral. However, in most practical scenarios, loads are not perfectly balanced, and the neutral conductor safely carries the difference in current. It also serves as a return path for single-phase loads connected between a phase conductor and neutral.

The grounding of the neutral point is crucial for safety. It limits the voltage stresses on insulation during faults, such as a short circuit to ground. It also provides a path for fault current to flow back to the source, allowing protective devices like circuit breakers and fuses to detect the fault and disconnect the power. Different earthing methods exist, such as TN, TT, and IT systems, which define the specific way the neutral is connected to earth and metallic enclosures. The choice of earthing system impacts safety, reliability, and system design.