A New Approach to Reactive Power Calculation of the Static VAr Compensator

By A Osnach

This paper presents a new approach to the calculation of reactive power of a static VAr compensator with controlled inductance. The key idea underlying the approach is to use the distinction between the concept of “electromotive force (EMF) of power source” and “input voltage of electric circuit”, causing the current to flow. In order to determine the reactive power of controlled inductance, the only part of the input voltage connected with the current flowing through the reactor should be taken into consideration. Based on this approach, more accurate formulae for the reactive power of fundamental harmonic of the controlled inductance are proposed. The technique allows calculation of the reactive power for other harmonics as well. The calculated expressions and values estimation for reactive power of n-th harmonic are also presented. The recommendations supported by the results of this study are made. The proposed technique is compared with traditional approach.