Statistical analysis of residential harmonic spectrum in Costa Rica

The adoption of new technologies interfaced with the electricity system via inverters is likely to affect the quality of the power supply. To understand this, however, it is important to first capture the existing harmonic spectrum of residential loads. This paper presents results of a statistical study of current harmonic spectrum measured at the service point of residential customers in the central region of Costa Rica. A total of 367 different customers were analyzed as part of a nationwide power quality measurement campaign. The measured data were studied and classified per time stamp and harmonic order differentiating weekdays from weekends. The study demonstrates the variability of harmonic components of aggregated residential loads at different hours of the day, as it depends on the type of appliance in use. These results are intended to be used as input parameters of future low voltage harmonic power flow studies.