HARMONIC VOLTAGE GENERATION DUE TO FILTER COMPONENT TOLERANCES.
An investigation and analysis were done on resonance conditions in a specific system coupled to a supply with varying source impedance. Harmonic current injection of other consumers on the same supply system was also considered. Initially a model in which all harmonic generators were presented by harmonic current sources was used to determine the currents through and voltages at the harmonic filters of the system. This model provides information of the severity of the resonances and of the effect of tolerances in the filter components. In order to locate the exact cause of the resonances, admittance and impedance plots vs frequency at different points in the overall system were drawn. From these plots the possibility of resonance conditions in the industrial system itself was traced.