CURRENT HARMONIC DISTORTION IN OFFICE BUILDING ELECTRIC NETWORK

This paper presents an analysis of the current harmonic distortion at the point of common coupling of an office building. At first the problem of the harmonic distortion of the current wave-shape is analysed for lighting systems and office equipments. Measurements are presented for each type of office load, with the purpose of emphasising the non-linear load characteristics. Next the problem of assessing the current harmonic distortion at the point of common coupling is analysed. A case study is presented, where the harmonic distortion of the current wave-shape is analysed for an office building, based on individual equipment measurements and 24-hour load operation profile. Two scenarios are discussed: with and without the implement of occupancy sensors in office rooms. It can be seen in both scenarios that the harmonic current distortions closely correlate with the fundamental current (power demand) of the office load. The use of occupancy sensors brings important energy savings, with the cost of slightly higher current harmonic distortion.