Overskuddsharmoniske

Overskuddsharmoniske, often translated as surplus harmonics or excess harmonics, refers to the generation of unwanted harmonic frequencies in electrical systems that go beyond the expected levels. In a typical AC power system, the fundamental frequency is the desired waveform, usually 50 or 60 Hz. Harmonics are integer multiples of this fundamental frequency. While some harmonics are naturally present and generally harmless at low levels, overskuddsharmoniske imply a significant and problematic increase in their magnitude.

These excess harmonics are predominantly caused by non-linear loads. Non-linear loads are devices that draw current that is not directly proportional to the applied voltage. Examples include rectifiers, variable frequency drives, switching power supplies found in computers and electronics, and certain types of lighting. As these devices switch on and off rapidly, they create distorted current waveforms, which in turn generate a broad spectrum of harmonic frequencies.

The presence of overskuddsharmoniske can lead to several detrimental effects. They can cause overheating of transformers, motors, and conductors due to increased RMS current. This can reduce equipment lifespan and increase the risk of failure. Furthermore, they can interfere with sensitive electronic equipment, leading to malfunctions or data corruption. Flickering lights, especially in older incandescent systems, can also be a symptom. In communication systems, overskuddsharmoniske can induce noise and crosstalk, degrading signal quality.

Mitigation strategies for overskuddsharmoniske typically involve the installation of harmonic filters. These can be passive filters, consisting of inductors and capacitors, or active filters, which use electronic components to actively counteract the harmonic currents. Proper design of electrical systems and careful selection of equipment can also help minimize the initial generation of these unwanted frequencies.