Analysis of power quality problems in low-voltage circuits

This paper presents the analysis and the diagnosis of two cases with power quality problems in AES SUL´s commercial/residential customers, fed through low-voltage net. After a lot of monitoring of the customers´ feeding voltage, performed using specific equipment and a detailed and careful investigation, it was determined that the causes of the disturbances derived from the customers´ systems themselves. Then, the main steps used in the in the analysis and the results of the measurements that led to the identification of the problems are described.