The electrical power quality indicator – interference power factor

Abstract

Purpose. Substantiation of the methodology for calculating an indicator characterizing the pulsating current power distortion. Methodology. When analyzing the power of direct and alternating sinusoidal currents, the features of the ratio of a root-mean-square norm to its mean value, known as the invariance power factor, are noted. In this case, the root-mean-square power value acts as a normalizing parameter. Using a combination of direct and sinusoidal (pulsating) current, the dependences of the invariance power factor on the ratio of direct and alternating components are obtained. Findings. Taking into account the interaction of the current and voltage components of different frequencies, the corresponding power component is highlighted, called interference power. With its use, by analogy with the invariance power factor, the interference power factor is introduced. The interference power factor behavior for AC non-sinusoidal current circuit and DC pulsed current circuit of rectifier was investigated, as a result of which a difference was established in the interference power factor dependence in these circuits. Originality. The obtained dependences of the interfere power factor on the ratio of DC and AC components for current and voltage prove the versatility of its application for assessing power distortion in both DC and AC circuits, as proved by the example of a circuit with a single-phase controlled rectifier. Practical value. The results obtained can be used to assess the electrical power distortion level in electric complexes and systems of various kinds of current and kind of energy, including when it is taken into account. This is a prerequisite for the measures development to improve the electricity quality.