Effect of distributed generation on voltage flicker in distributed systems: A case study

The use of distributed generation (DG) in distribution system is expected to increase in the near future due to its positive impacts such as voltage support, improved reliability, small size and losses reduction. However DGs may have negative impacts on power quality, such as voltage regulation, harmonic distortion, islanding and confliction with relaying and reclosing. This study investigates the impact of DGs on voltage flicker which is considered recently as an urgent power quality problem that can affect motor starting, temperature rise, overloading of generators, motors and may cause health risk problems due to the annoying light flicker which is consequence of voltage fluctuation. The study includes three days monitoring of a residential building with and without DG connected. Results obtained reveal a strong relation between voltage frequency deviations produced in the presence of DG and the voltage flicker detected.