Flicker propagation and emission coordination study in a simulated low voltage network

Voltage flicker is an irritating problem especially for the low voltage (LV) customers. It is mainly caused by the loads having repetitive cycle of operation. During the past years, the network operators around the world have registered many complaints from the customers about flicker related problems. Presently, there is no common standard value for the flicker planning level available globally. Moreover, in some countries (for example, in the Netherlands), the existing networks are not even based on a specific planning level value for flicker. Therefore, it is necessary to discuss the flicker planning level values in different voltage levels to overcome flicker related problems. In this paper a typical LV network is simulated to analyze the flicker propagation behavior in the network. The effects of switching LV disturbing loads (such as elevator, welding machine, etc.) on flicker generation at different customer's installations are studied by using synchronized measurement technique. Also, the impacts of the background flicker pollution transferred from the upstream to the downstream networks are analyzed. The simulation results give an overview of the flicker pollution levels at the LV customer's installations in the presence of background flicker. This paper estimates the maximum value of flicker emission share at different customer's point of connections (POC), considering the impact of background flicker pollution. Finally, planning level values of flicker in different voltage levels are suggested that can be useful for the network operators in designing their future networks.