Survey of a power quality measurement campaign in low-voltage grids

With an increasing share of renewable energy generation becoming connected to distribution grids, power quality has attracted the attention of grid operators and academia. However, to obtain a realistic picture, power quality distortions caused by renewables should be superimposed on already existing emissions in grids. Measured household load data is tedious to acquire and is not publicly available. This paper presents the data from a low-voltage feeder measurement campaign and it is divided into voltage and feeder current analyses. The voltage parameters are validated as per EN 50160. The measured data includes measurements from feeders supplying single-family homes as well as one apartment building. A total of 24 weeks of 10-second mean values were recorded in the Helsinki region of Finland. Results indicate that the voltage quality is within the acceptable limits. The feeder currents show load unbalance in single-family homes and high utilisation rate of feeders supplying multiple customers.