HOW THE HARMONIC OSCILLATION DANGEROUS?
High level of harmonic distortion can create stress and resultant problems for the utility’s distribution system, the plant’s distribution system, as well as the plants equipment. Equipment shutdown can result from too-high levels of harmonic distortion. Following is the list of problems that enhanced harmonic distortion can create : • The capacitors are subjected to a voltage overload and their lifetime is drastically reduced; in fact the voltage drop across the capacitor caused by each of the harmonic currents present must be added to the fundamental voltage. This over voltage is well above 10% when resonance is present, causing the premature dielectric breakdowns. • Connection of the cap. causes a large increase in the voltage distortion factor THD(V). • Motors; Reduced motor life, inability to fully load motor. • The user transformers, wires and loads are affected by this increase in current, which leads to increased I2 R losses and eddy current losses in transformer. This reduces
